Kind: captions
Language: en
the following is a conversation with
catherine declare a professor of
planetary science and astronomy at
caltech
her research is on the surface
environments atmospheres
and thermochemical histories of the
planets and moons
in our solar system quick mention of our
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as a side note let me say that this
conversation and a few others
quite big ones actually that are coming
up were filmed in a studio where i was
trying to outsource some of the work
like all experiments it was a learning
experience for me it had some positives
and negatives ultimately i decided to
return back to doing it the way i was
doing before
but hopefully with a team who can help
me out
and work with me long term the point is
i will always keep challenging myself
trying stuff out learning growing and
hopefully improving over time
my goal is to surround myself with
people who love what they do
are amazing at it and are obsessed with
doing the best work of their lives
to me there's nothing more energizing
and fun than that
in fact i'm currently hiring a few folks
to work with me on various small
projects
if this is something of interest to you
go to lexfriedman.com
hiring that's where i will always post
opportunities for
working with me this is the lex friedman
podcast
and here is my conversation with
catherine to clear
why is pluto not a planet anymore does
this upset you or
has justice finally been served
so i get asked this all the time i think
all planetary scientists get asked about
pluto especially by kids who
would just love for pluto to still be a
planet um
but the the reality is um when we first
discovered pluto it was it was a unique
object in the outer solar system and we
thought
you know we were adding a planet to the
inventory of planets that we had and
then
over time it became clear that pluto was
not
a unique large object in the outer solar
system that there were actually
many of these and as we started
discovering more and more of them we
realized that the concept of pluto being
a planet
um didn't make sense unless maybe we
added all the rest of them as planets so
you know you could have imagined
actually a different direction that this
could have gone
where all the other objects that were
discovered in that belt
or at least all the ones let's say above
above a certain size
became planets instead of pluto being
declassified
but we were now aware of many objects
out there in the outer solar system and
what's called the kuiper belt that are
of the same size or in some cases even
larger than pluto
um so the the declassification was
really just a realization that it was
not
in the same category as the other
planets in the solar system and we
basically needed to refine our
definition
in such a way that took into account
that there's this this
belt of debris out there in the outer
solar system of things with a range of
sizes
um is there a hope for clear
categorization
of what is a planet and not give us or
is it all just gray area
when you study planets when you study
moons satellites of those planets
is there lines that are cl that could be
cleanly drawn or is it just a giant mess
this is all like a fluid let's say not
mess but it's like fluid
uh of what is a planet what is the moon
of a planet what is debris
what is asteroids all that kind of so
there
are technically clear definitions that
were set down by the iau
the international astronomy union
um is it size related like what are the
parameters based on so the parameters
are
that it has to orbit the sun which was
essentially to rule out satellites of
course this was a
not very forward-thinking definition
because it technically means that all
extrasolar planets according to that
definition are not planets
um so it has to order uh orbit the sun
it has to be
large enough that its gravity has caused
it to become spherical in shape
which also applies to satellites and
also applies to pluto the third part of
the definition is the thing that really
rules out everything else which is that
it has to has
have cleared out its orbital path um
and because pluto orbits in a belt of
material it doesn't satisfy
that stipulation why didn't it clear out
the path it's not big enough
right knock everybody out of the way um
and this actually is not the first time
it has happened so
series when it was discovered ceres is
the largest asteroid in the asteroid
belt
and it was originally considered a
planet when it was first discovered and
it went through
exactly the same story history where
people actually realized that it was
just one of many asteroids in the
asteroid belt region and then it got
declassified to an asteroid and now it's
back to a dwarf planet
so there is a lot of reclassification so
to me as somebody who studies
solar system objects i
just personally don't care my level of
interest and something has nothing to do
with
what it's classified as so my favorite
objects in the solar system are all
moons and frequently when i
talk about them i refer to them as
planets because to me they are
planets they have volcanoes they have
geology they have atmospheres they're
planet-like
worlds and so the distinction is not
super meaningful to me
but i it is important just for having a
general framework
for for understanding and talking about
things to have a precise definition
so you don't have a special romantic
like appreciation of a moon versus a
planet versus an asteroid it's just an
object that flies out there and doesn't
really matter
what the categorization is because
there's movies about asteroids and stuff
and then there's like and then there's
movies about you know
the moon whatever it's a really good
movie
you know there's something about moons
that uh that's almost like
an outlier like you think of a moon
as a thing that's the secret part and
the planet
is like the more like vanilla regular
part
none of that you don't have any of that
no i actually do i really satellites are
the moons are my favorite things in the
solar system and i think part of
what you're saying i agree from
maybe a slightly different perspective
which is from the perspective of
exploration
we've spent a lot of time sending
spacecraft missions to planets we had a
mission to jupiter we had a mission to
saturn we have plenty of missions to
mars and missions to venus
i think that exploration of the moons in
the outer solar system is
the next frontier of solar system
exploration
the belt of debris just real quick
that's out there
is there something incredible to be
discovered there
again we tend to focus on the planets
and the moons but it feels like
there's probably a lot of stuff out
there and it probably
what is it it's like a garbage collector
from
outside of the solar system isn't it
like doesn't it protect
from other objects that kind of fly in
and what it just feels like
it's a cool you know you know when you
like walk along the beach and look for
stuff
and like look for sure it feels like
that's that kind of place where you can
find cool
cool weird things or it i guess
in our conversation today when we think
about tools and what science is
studying is there something to be
studied out there or we just don't have
maybe the tools yet or there's nothing
to be found
there's there's absolutely a lot to be
found so the material that's out there
is remnant
material from the formation of our solar
system it's we don't think it comes from
outside the solar system at least not
most of it
but there are so many
fascinating objects out there and i i
think what you fit on is exactly right
that we just don't have the tools to
study them in detail
but we we can look out there and we can
see there are different species of ice
on their surface that tells us about
you know the chemical composition of the
disc that formed our solar system
some of these objects are way brighter
than they should be meaning they have
some kind of geological activity people
have hypothesized that some of these
objects have subsurface oceans
you could even stretch your imagination
and say some of those oceans could be
habitable
but we can't get very detailed
information about them because they're
so far away and so i think
if any of those objects were in the
inner solar system it would be studied
intently and would be very interesting
so would you be able to design a probe
in that like very dense debris field
be able to like hop from one place to
another is that just outside the
realm of like how would you even design
devices or sensors that go out there
and take pictures and and land do you
have to land to truly understand
a little piece of rock or can you
understand it from
remotely like fly up close and remotely
observe
you can learn quite a lot from just a
flyby and that's all we're currently
capable of doing in the outer solar
system
um the new horizons mission is a recent
example which flew by pluto and then
they had searched for another object
that was out there in the kuiper belt
any object that was basically
somewhere that they could deflect their
trajectory to actually fly by and so
they did fly by
another object out there in the kuiper
belt and they take pictures and they do
what they can do and if you've seen the
images from
that mission of pluto you can see just
how much detail we have compared to just
the sort of reddish dot that we knew of
before
so you do get an amazing amount of
information actually from just
essentially a high speed flyby it always
makes me
sad to think about flybys that we might
be able to
we might fly by a piece of rock take a
picture
and think oh that looks pretty and cool
whatever and that you could study
certain like composition of the surface
and so on but it's actually
teeming with life and we won't be able
to see it
at first it's sad because
you know like when you're on a deserted
island you wave your hands and the thing
flies by and you're
trying to get their attention and they
probably do the same
well in their own way bacteria probably
right but
and we we miss it i don't know some
reason it makes me it's a
it's the fomo it's fear of missing out
it makes me sad that there might be life
out there
and we don't we're not in touch with it
we're not talking yeah well
okay uh a sad uh
pause uh russian philosophical pause
okay what are the tools available to us
to study planets and their moons
oh my goodness that is such a big
question um
so among the fields of astronomy so
planetary science broadly speaking
well it falls kind of at the border of
astronomy
geology climate science chemistry and
even biology so it's kind of on the
border of many things but
part of it falls under the heading of
astronomy and among the things that you
can study
with telescopes like solar system moons
um and planets
the solar system is really unique in
that we can actually send
spacecraft missions to the objects and
study them in detail and so i think
that's that's the kind of type of tool
that is that people are most aware of
this most popular eyes
these amazing nasa missions that either
you fly by the object you orbit the
object you land on the object
potentially you can
talk about digging into it drilling um
trying to detect tectonic tremors on its
surface
um the types of tools that i use
are primarily telescopes and so i my
background is in
astrophysics and so i actually got into
solar system science from
astronomy not from you know a childhood
fascination with spacecraft missions
which is actually what
a lot of planetary scientists became
planetary scientists because of
childhood fascination with spacecraft
missions which is kind of interesting
for me to talk to people and see that
trajectory i kind of came at it from the
fascination with telescope's angle
do you like telescopes not rockets or at
least when i was a
kid it was looking at the stars and
playing with telescopes that really
fascinated me and that's how i got into
this
but telescopes it's
amazing how much detail and how much
information you can get from
telescopes today you can resolve
individual cloud features and watch them
kind of sheer out in the atmosphere of
titan you can
literally watch volcanoes on io change
from day to day as the the lava flows
expand
so and then you know with spectroscopy
you get compositional information on all
these things and
it's when i started doing solar system
astronomy i was
surprised by how much detail and how
much information you can get
even from earth and then as well as from
orbit like the hubble space telescope or
the james webb
so with the telescope you can
i mean how much information can you get
about volcanoes about
storms about sort of weather
just so we kind of get a sense like what
a resolution we're talking about
well in terms of resolution so at a you
know on a given night if i go and take a
picture of io and it's volcanoes you can
sometimes see
at least a dozen different volcanoes you
can see the infrared emission coming off
of them and
resolve them separate them from one
another on the surface
and and actually watch how how the heat
coming off of them changes with time
and i think this time variability aspect
is one of the big advantages we get from
telescopes so you send a spacecraft
mission there
and you get an incredible amount of
information over a very short time
period but for some
science questions you need to observe
something for
30 years 40 years like let's say you
want to look at the moon
titan which has one of the most
interesting atmospheres in the solar
system
it's orbital period is 29
30 years and so if you want to look at
how
its atmospheric seasons work you have to
observe it over that long of a time
period and you're not going to do that
with a spacecraft
but you can do it with telescopes can we
uh just
zoom in on certain things like let's
talk about io which is the moon of
uh jupiter right okay it's like epic
there's like volcanoes all over the
place
it's um from a distance it's awesome
so can you tell me about this moon and
you're
sort of uh a scholar of many planets and
moons
but that one kind of stood out to me so
why is that an interesting one
for so many reasons but uh io is it is
the most volcanically active object in
the solar system it has hundreds of
active volcanoes on it
um it has volcanic plumes that go
hundreds of kilometers up above its
surface it puts out
more volume of magma per volcano than
volcanoes on earth today um but
i think to me the reason that it's most
interesting is be
is as a laboratory for understanding
planetary processes
so one of the broad goals of planetary
science is to put together
a sort of more general and coherent
framework for how planets work in
general
our current framework you know it
started out very earth-centric we start
to understand how earth volcanoes work
um but then when you try to transport
that to somewhere like io that doesn't
have an atmosphere which makes it
has a very tenuous atmosphere which
makes a big difference for how the the
magma d gases
for something that's really small for
something that has a different heat
source for something that's embedded in
another object's magnetic field
the kind of intuition we have from earth
doesn't apply and so broadly
planetary sciences is trying to broaden
that framework
so that you have a kind of narrative
that all you can understand how each
planet became different from
every other planet and i'm already
making a mistake when i say planet i
mean planets and moons
like i said i see the moons as planets
yeah i actually already noticed that you
didn't introduce io as the moon of
jupiter
you you completely you uh you kind of
ignored the fact that jupiter exists
it's like let's focus on this
yeah okay so uh and you also didn't
mention europa
which i think is the is that the most
famous moon of jupiter
it's like no one gets attention because
it might have life exactly
yeah but you're but to you i o is also
beautiful
i what's the difference between
volcanoes on io
versus earth you said atmosphere makes a
difference
what uh yeah um the heat source plays a
big role so
um many of the moons in the outer solar
system are heated
from gravitationally by tidal heating um
and i'm
happy to describe what that is or well
yeah please
okay um yes so tidal heating
is it's if you want to understand and
contextualize
planets and moons you have to understand
their heat sources
um so for earth we have radioactive
decay in our interior as well as
residual heat of formation
but for satellites tidal heating plays a
really significant role and in
particular in
driving geological activity on
satellites
and potentially making those subsurface
oceans in places like europa enceladus
habitable and so the way that that works
is if you have multiple moons
and their orbital periods are integer
multiples of one another
that means that they're always
encountering each other
at the same point in the orbit
so if they were on just random orbits
they'd be encountering each other at
random places and the gravitational
effect between the two moons would be
canceling out over time but because
they're always meeting each other at the
same point in the orbit
those gravitational interactions add up
coherently
um and so that tweaks them into
eccentric orbits
so eccentric orbit or elliptical orbit
it just means
non-circular so a deviation from a
circular orbit and that means that you
know for io or europa
it's some points in their orbit they're
closer to jupiter and at some points in
the orbit they're farther away
and so when they're closer they're
stretched out in a sense but but
literally just not very stretched out
like a couple hundred meters something
like that
and then when they're farthest away
they're less stretched out and so you
actually have the shape of the object
deforming over the course of the orbit
and these orbits are like just a couple
of days
and so that in the case of io that is
literally
sufficient friction in its mantle to
melt the rock of its mantle
and that's what generates the magma
that's that's the source of the
the okay so why is your so europa
is i thought there was like ice and
oceans underneath kind of thing
so why is europe and not getting the
friction it is it's just a little bit
farther away from jupiter and then
ganymede is also
in the orbital resonance so it's a three
object orbital resonance
in the jupiter system but we have these
sorts of orbital resonances all over the
solar system and also in exoplanets
so for europa basically because it's
farther from jupiter the effect is not
as extreme but you do still have heat
generated in its interior in this way
and that may be driving
could be driving hydrothermal activity
at the base of its ocean
which obviously would be a really
valuable thing for life
cool so it's like heating up the ocean a
little bit
heating up the ocean a little bit and
specifically in these like hydrothermal
vents where we see really interesting
uh life evolve in the bottom of earth's
oceans
that's cool okay so what's uh what's io
um what else so we know the source is
this friction
but there's no atmosphere i'm trying to
get a sense of what it's like if
if you and i were to visit io
like what would that look like what
would it feel like
is it is the entire thing covered in
basically
uh volcanoes um
so it's it's interesting because there's
very little atmosphere the surface is
actually really cold
very far below freezing on the surface
when you're away from a volcano but the
volcanoes themselves
are over a thousand degrees or the the
magma when it comes out is over a
thousand degrees and so
but it does come to the surface the
magma it does yeah
in particular places oh that probably
looks beautiful
so like so it's frozen not ice like what
is
uh is rock it's really cold rock
and then you just have this like uh
what is what does that look what would
that look like with no atmosphere
would that uh would it be smoke
what does it look like was it's just
magma like just red
yellow like liquidy things uh it's
it's black it's black and red i guess
like think of
the type of magma that you see in hawaii
so different types of magma
flow in different ways for example so in
somewhere like io the magma is really
hot and so it will flow out in
sheets because it has really low
viscosity
um and i think the the lava flows that
we've been having
in hawaii over the past couple years are
probably a decent analogy although um
ios magmas lavas are even more fluid and
and faster moving like what uh how fat
like
if you oh by the way sorry through the
telescope
are you tracking at what time scale like
what the for every frame
is how far apart if you're looking for a
telescope are we talking about
seconds or we're talking about days
months
when you kind of track try to get a
picture of what the surface might look
like
what's the frequency so it depends a
little bit on what you want to do
i ideally every night
but you could take a frame every second
and see how things are changing
the the problem with that is that for
things to change on a one
second time scale you to actually see
something change that fast you have to
have super high resolution the spatial
resolution we have is a couple hundred
kilometers and so
okay things are not changing on those
scales over one second unless you have
something really crazy happening
so if you get you if you get a telescope
closer to io
if you get uh or a camera closer to io
would you be able to understand
something is that something of interest
to you
it would you be able to understand
something deeper about
these volcanic eruptions and how magma
flows and
just the like the rate of the magmas or
is it basically
enough to have the kilometer resolution
no way
we want to go there you want to go you
want to go to iowa i mean i don't want
to go there personally but i want to
send a spacecraft mission there
absolutely
why why are you scared why am i scared
oh you mean you don't
like i don't want to go there as a human
human
i want to send a robot there to look at
it this is again everybody's
discriminating against robots this is
not but it's fine uh but it's not
hospitable to uh
humans in any way right so it's very
cold and very hot
it's very cold um the atmosphere is
composed of sulfur dioxide
so you couldn't breathe it there's no
pressure i mean it's kind of all the
same things you talk about
one talks about about mars only worse
the atmosphere is still a thousand times
less dense than mars's
and the radiation environment is
terrible because you're embedded
deep within jupiter's magnetic field and
jupiter's magnetic field is
full of charged particles that have all
come
out of ios volcanoes actually um so
juveder's magnetic field strips all this
material out of ios atmosphere
and that populates its entire
magnetosphere and then that material
comes back around and hits io and
spreads throughout the system actually
it's just
it's like a io is the massive polluter
of the jupiter system
okay cool uh so what uh what is studying
io
uh teach you about volcanoes on earth or
vice versa
is in the difference of the two
what uh insights can you mine out
that might be interesting in some way
yeah it's
we try to port the tools that we use to
study earth volcanism to io and it works
to some extent but
it is challenging because the
situations are so different and the
compositions are really different when
you talk about
outgassing you know earth volcanoes
outgas primarily
water and carbon dioxide and then sulfur
dioxide is the the third
most abundant gas and and on io the
water and carbon dioxide are not there
either it didn't form with them or it
lost them we don't know and so so the
chemistry of how the magma outgasses is
completely different
um but the the kind of one to me
most interesting analogy to earth is
that
um so io as i've said it has these
really low viscosity magmas the
the lava spreads really quickly across
its surface
it can put out massive volumes of magma
in relatively short periods of time
and that sort of volcanism is not
happening anywhere else in the solar
system today
but literally every terrestrial planet
and the moon
um had this what we call very effusive
volcanism early in their history okay so
this is almost like a little glimpse
into the early history of earth yeah
okay cool so uh what are the chances
that uh a volcano on earth destroys all
of human civilization
maybe i wanted to sneak in that question
yeah a volcano on earth
um do you think about that kind of stuff
when you just
study volcanoes elsewhere because in it
kind of humbling to see something so
powerful
and so hot like so unpleasant for humans
and then you realize we're sitting on
many of them here right
yeah yellowstone as a classic example i
i don't
know what the chances are of that
happening my intuition would be that the
chances of that are lower than the
chances of
us getting wiped out by some other means
so that in the time
you know that maybe it'll happen
eventually that there will be one of
these massive volcanoes on earth but
we'll probably be gone by then by some
other means
not to sound bleak but it's very
comforting
okay so can we talk about um europa
is there um so maybe can you talk about
the intuition the hope that people have
about life being in europa
maybe also what are the things we know
about it
what are things to you that are
interesting about that particular moon
of jupiter
sure yeah europa is from many
perspectives one of the really
interesting
places in the solar system among the
solar system moons so there are a few
there has there's a lot of interest in
looking for or understanding the
potential for life to evolve in the
subsurface oceans
i think it's fairly widely accepted that
the chances of life evolving on the
surfaces of really anything in the solar
system is very low
the radiation environment is too harsh
and there's there's just not liquids on
the surface of most of these things and
it's canonically accepted that liquids
are required for life
um and so the subsurface oceans in
addition to maybe titan's atmosphere the
subsurface oceans of the icy satellites
uh are one of the most plausible places
in the solar system for life to evolve
europa and enceladus are interesting
because for many of the big satellites
so
ganymede and callisto also satellites of
jupiter also are thought to have
subsurface oceans
but um they are so they have these ice
shells and then there's an ocean
underneath the ice shell
but on those moons around ganymede we
think that there's another ice shell
underneath
and then there's rock and the reason
that that is a problem for life is that
your ocean is probably just pure water
because it's trapped between two
big shells of ice uh so europa
doesn't have this ice shell at the
bottom of the ocean we think
and so the water and rock are in direct
interaction and so that means that you
can basically dissolve a lot of material
out of the rock you potentially have
this hydrothermal activity that's
injecting
energy and nutrients for life to survive
and so this
water interface is is considered really
important
for the potential habitability
as a small aside you kind of said that
it's canonically assumed that
uh light water is required for life
is it possible to have life uh like in
the volcano
i remember people are at that like in
that
national geographic program or something
kind of hypothesizing that you can
really have life anywhere so as long as
there's a source of heat
a source of energy do you think it's
possible to have
life in a volcano like no water
i think anything's possible
i think it's so water it doesn't have to
be
water that's sort of you can tell as you
identified i phrased that really
carefully it's canonically accepted that
um because we recognize that you know
scientists recognize that we have no
idea
what broad range of life could be out
there and all we really have is our
biases of life as we know it
but for life as we know it it's very
helpful to have or even necessary to
have some kind of
liquid and preferably a polar solvent
that can actually dissolve molecules
something like water so the case of
liquid methane on titan is less ideal
from that perspective
but you know liquid magma if it stays
liquid
long enough for life to evolve you have
a heat source you have a liquid you have
nutrients in theory that checks your
three
classic astrobiology boxes
um that'd be fascinating i mean it'd be
fascinating if it's possible to detect
it easily
how would we detect if there is life on
europa
is um is it possible to do in a
non-contact way
from a distance through telescopes and
so on
or do we need to send robots and do some
drilling
i think realistically you need to do the
drilling um
there's so europa also has these long
tectonic features on its surface where
it's thought that
there's potential for water from the
ocean to be somehow making its way
up onto the surface and you could
imagine some out there scenario where
there's bacteria in the ocean it's
somehow working its way up through the
ice shell
it's spilling out on the surface it's
being killed by the radiation
but your instrument could detect some
spectroscopic signature of that
dead bacterium but that's you know
that's many ifs and assumptions
that's a hope because then you don't
have to do that much drilling you can
collect from the surface right or even
i'm thinking even remotely oh remotely
yeah that's sad that there's a
single cell civilization living
underneath all that ice
trying trying trying to get up trying to
get out
so enceladus gives you a slightly better
chance of that
because enceladus is a is a moon of
saturn
and it's broadly similar to europa in
some ways it's an icy satellite it has a
subsurface ocean that's probably
in touch with the rocky interior but it
has these massive
geysers at its south pole where it's
spewing out material that appears to be
originating all the way from the ocean
and so in that case you could
potentially fly through that plume and
scoop up that material and hope that at
the velocities you'd be scooping it up
you're not destroying any signature of
the life you're looking for
but let's say that you have some
ingenuity and can come up with a way to
do that
you know it potentially gives you a more
direct opportunity at least to try to
measure those bacteria directly
can you tell me a little more on uh how
do you pronounce it
enceladus enceladus can you tell me a
little bit more about enceladus
like uh we've been talking about way too
much about jupiter
saturn doesn't get enough
uh saturn doesn't get as much love so
what's what's enceladus uh
is that the most exciting moon of uh
saturn
depends on your perspective um it's it's
very exciting from a
astrobiology perspective i think
enceladus and
titan are the two most unique and
interesting moons of saturn that
definitely both get the most
attention also from the life perspective
um
so what's more likely uh titan or
enceladus for life
if you were to uh bet all your money in
terms of like investing
wish to investigate what what are the
difference between the two
that are interesting to you yeah so
the potential for life in each of those
two places is very
different so titan is the the one place
in the solar system where you might
imagine again all of this is so
speculative but you might imagine
life evolving in the atmosphere so the
from
a biology perspective titan is
interesting because
it forms complex organic molecules in
its atmosphere
it has a dense atmosphere it's actually
denser than earth's it's the only moon
that has what
an atmosphere denser than earth it's got
tons of methane in it what happens is
that methane gets irradiated it breaks
up and it reforms with other things in
the atmosphere
it makes these complex organic molecules
and it's effectively doing prebiotic
chemistry in the atmosphere
while still being freezing cold uh
yes okay what what would that be like
would that be pleasant for humans to
hang out there
it's just really cold there's nowhere in
the solar system that would be pleasant
for humans
um it would be cold you couldn't breathe
the air um
but colonization wise if there's an
atmosphere isn't that a big plus
or still a ton of radiation
so okay so titan
that that's a really nice feature that
the light could be in the atmosphere
because then it's it's that might be
remotely observable or certainly is more
accessible if you visit okay
so uh what about enceladus so that would
be
still in the ocean right and enceladus
has
the advantage like i said of spewing
material out of its south pole so you
could collect it but it has
the disadvantage of the fact that we
don't actually really understand
how its ocean could
stay froze or sorry could stay globally
liquid
over the age of the solar system and so
there are some models that say
that it's going through this um cyclical
evolution
where the ocean freezes completely and
thaws completely and the orbit sort of
um oscillates in and out of these
eccentricities um and in that case
the potential for life ever occurring
there in the first place is a lot lower
because if you only have an ocean for
100 million years
is that enough time and it also
means there might be mass extinction
events if it does occur
right it just freezes again very sad man
this is very depressing all the like
slaughter of
life elsewhere how unlikely do you think
life is on earth so when you look
when you study other planets and you
study the contents of other planets
does that give you a perspective on
the origin of life on earth which again
is full of mystery
in itself not the evolution but the
origin
the first springing to life like from
from nothing to life from the basic
ingredients to life
and i guess another way of asking it is
how unique are we
yeah it's a great question and it's one
that
just scientifically we don't have an
answer to
we don't even know how many times life
evolved on earth if it was only once or
if it happened independently a thousand
times in different places
uh we don't know whether it's happened
anywhere else
in the universe although it feels absurd
to believe
that we are the only life that evolved
in the entire universe but
it's conceivable we just have just no
real information we don't understand
really how life came about in the first
place on earth
i mean so if you look at the drake
equation
that tries to estimate how many alien
civilizations are out there
planets have a big part to play in that
equation
if you were to bet money uh
in terms of the odds of origins of life
on earth
i mean this all has to do with how
special and unique is earth
what you land in terms of the number of
civilizations has to do with
how unique their rare earth hypothesis
is how
rare special is earth how rare and
special is the solar system
like if you had to bet all your money on
a
on a completely unscientific question
well no actually it's actually
rigorously scientific we just don't know
a lot of things
in that equation there's a lot of
mysteries about that
and it's slowly becoming better and
better understood in terms of exoplanets
in terms of
how many solar systems are out there
where there's planets their earth-like
planets is
getting better and better understood
what's your sense
from that perspective um how many alien
civilizations out there
so zero or one you're right that the
equation
is is being better understood but you're
really only talking about the first
three parameters in the equation or
something you know how many stars are
there how many planets per star
and then we're just barely scratching
the surface of what fraction of those
planets might be habitable
the rest of the terms in the equation
are like how likely is life to evolve
give inhabitable conditions how likely
is it to survive all these things
um they're all these huge unknowns
actually i i remember when i first
saw that equation i think i was i think
it was my first year
of college and i thought this is
ridiculous this is
a common sense that didn't need to give
a given name
you know um and b just a bunch of
unknowns it's like
putting our ignorance together in one
equation but i've actually
now i understand this equation you know
it's not
something we ever necessarily have the
answer to it's
it just gives us a framework for having
the exact conversation we're having
right now
and i think that's how it was intended
in the first place when it was was put
into writing was to to give people a
language to communicate about
the factors that go into the potential
for aliens to
be out there and for us to find them um
i i would
put money on there being aliens i
would not put money on
us having definitive evidence of them in
my lifetime
well definitive is a funny is a funny
word
because uh my sense is this is the
saddest part
for me is my sense in terms of
intelligent alien civilizations
i feel like we're so
we're so self-obsessed that we literally
would not be able to detect them
even when they're like in front of us
like like
trees could be aliens but just their
intelligence could be
realized on a scale on a time scale
or physical scale that we're not
appreciating
like trees could be way more intelligent
than us
i don't know it's just a dumb example it
could be rocks rock
or it could be things like
this i love this this is the dawkins
memes it could be that ideas
are the like ideas we have like where do
ideas come from where do thoughts come
from
maybe thoughts are the aliens or
maybe thoughts is the actual mechanisms
of communication
in uh physics right this is like we
think of thoughts as something that
springs up from neurons
firing where the hell they come from
and now what about consciousness maybe
consciousness is the communication
it sounds like ridiculous but like
we're so self-centered on this uh
space-time
communication and physical space using
like written language
like spoken with audio
on a time scale that's very specific on
a physical scale it's very specific
uh so so i i tend to think that uh but
bacteria will probably recognize like
like moving organisms will probably
recognize but when that forms itself
into intelligence
most likely it'll be robots of some kind
because we won't be making
the origins we'll be meeting the
creations of those
intelligences we just would not be able
to to appreciate it and that's the
saddest thing to me
that uh we we
yeah we when we're too dumb
to see aliens uh like we're two
we kind of think like look at the
progress of science we've accomplished
so much
the sad thing it could be that we're
just like in the first point zero zero
zero one percent of understanding
anything it's humbling i hope that's
true
because i feel like we're very ignorant
as a species and i hope that our current
level of knowledge only represents the
0.001
of what we will someday achieve that
actually feels optimistic to me
well that i feel like that's easier for
us to comprehend in the space of biology
and not as easy to comprehend in the
space of physics for example
because we have a sense that like we
have
it like if you if you talk to
theoretical physicists
they have a sense that we understand the
basic laws
that form the nature of reality
of our universe but so there's much more
complex physicists and much more
confident
biologists are like uh
this is a squishy mess we're doing our
best
uh physicists but i would be it'd be
fascinating to see if physicists
themselves would also be humble
by their being like what the hell is
dark matter in dark energy
what what the hell is the not just the
origin of the
not just the big bang but uh everything
that happened since the big bang
a lot of things that happened since the
big bang we have no ideas about except
basic models of physics right
what happened before the big bang yeah
yeah what happened before
or what's happening inside the black
hole why is there a black hole at the
center of our galaxy
can somebody answer this a super massive
black hole
nobody knows how it started and they
seem to be like in the middle of all
galaxies
um so that could be a portal for aliens
to communicate through conscious okay
um all right back to planets how um
what's your favorite outside of earth
what's your favorite planet or moon
maybe outside of the ones well first
have we talked about it already
or and then if we did mention it what's
the one outside of that
oh gosh and to come up with another
favorite that's not io oh iowa's the
favorite oh absolutely why is iowa the
favorite
i mean basically everything i've i've
already said it's just such an amazing
and unique
object um but
on i guess a personal note it's probably
the object that
made me become a planetary scientist
it's
the first thing in the solar system that
really deeply captured my interest
um and when i started my phd i wanted to
be
an astrophysicist working on things like
galaxy evolution
um and sort of slowly i had done some
projects in the solar system but io was
the thing that like really caught me
in to doing solar system science okay
let's let's leave
uh moons aside what's your favorite
planet
it sounds like you like moons better
than planets so it's uh
that's accurate but the planets are are
fascinating i think
you know i find the planets in the solar
system really fascinating what i like
about the moons
is that they there's so much less that
is
known there's still a lot more discovery
space and the questions that we can ask
are still the the bigger questions
which you know i and maybe i'm being
unfair to the planets because we're
still
trying to understand things like was
there ever life on mars
and that is a huge question and one that
we've sent numerous
robots to mars to try to answer so maybe
i'm being unfair to the planets but but
there is
certainly quite a bit more information
that we have about the planets than the
moons
but i mean venus is is a fascinating
object so
i like the objects that lie at the
extremes
i think that if we can make a sort of
theory or
like i've been saying framework for
understanding planets and moons that can
incorporate even the most extreme ones
then you know those are the things that
really test your
theory and test your understanding and
so they've always really fascinated me
not so much the nice habitable places
like earth but
these extreme places like venus that
have
um sulfuric acid clouds and
just incredibly hot and dense surfaces
and venus of course
i love volcanism for some reason and
venus
has probably has volcanic activity
definitely has in the recent past maybe
has ongoing today what do you
make of the news maybe you can update it
in terms of life being discovered in the
atmosphere of
venus is that sorry okay
you have opinion i can already tell you
have opinions was that fake news
i got excited i saw that what's the
what's the final uh
is there a life on venus so the
detection that was reported was the
detection of the molecule phosphine
um and they said
that they tried every other mechanism
they could think of to produce phosphine
and they none of no mechanism worked
and then they said well we know that
life produces phosphine and so that was
sort of
the train of logic and um
i don't personally believe that
phosphene was detected in the first
place
okay so i mean this is just one study
but i
as a layman i'm skeptical
a little bit about tools that
sense the contents of an atmosphere like
contents of an atmosphere from remotely
and making conclusive statements about
life
oh yeah well that connection that you
just made the contents of the atmosphere
to the life
yeah is is a tricky one and
yeah i know that that claim received a
lot of criticism for
the lines of logic that went from
detection to
uh to claim of life even the detection
itself though
did doesn't doesn't meet the sort of
historical
scientific standards of of a detection
um the it was a very tenuous detection
and only one line of the species was
detected
and a lot of really complicated data
analysis methods had to be
applied to even make that weak detection
yeah
um so it could be it could be noise it
could be polluted data it could be all
those things and so it doesn't have it
doesn't meet the
the level of rigor that you would hope
but of course
i mean we're doing our best and it's
clear that uh
the human species are hopeful to find
life
clearly yes everyone is so excited about
that possibility
all right let's uh let me ask you about
mars
so um there's a guy named elon musk
and uh he seems to want to take
something called dogecoin there
first of the moon i'm just i'm just
kidding about the tushcoin i
i even know what the what the heck is uh
up with that whole uh
i think uh i think humor
has power in the 21st century
in a way to spread ideas in the most
positive way
so i love that kind of humor
because it makes people smile but it
also kind of
sneak it's like a trojan horse for cool
ideas
you you open with humor and you uh like
the humor is the appetizer and then the
main meal is the science and the
engineering
anyway uh do you think
it's possible to colonize
mars or other planets in the solar
system but we're
especially uh looking to mars is there
something about planets that make them
very harsh to humans
is there something in particular you
think about and maybe
in a high like big picture perspective
do you have a hope we
we do in fact become a multi-planetary
species
i do think that if our species
survives long enough and we don't wipe
ourselves out or get wiped out by some
other means
that we will eventually be able to
colonize other planets
i do not expect that to happen in my
lifetime i mean
tourists may go to mars tourists people
who commit
years of their life to going to mars as
a tourist may go to mars
um i don't think that we will colonize
it um
is there a sense why it's just too harsh
of an environment
to uh to to like it's too costly to
build something habitable there
for a large population
i think that we need to do a lot of work
and learning how to use the resources
that are
on the planet already to do the things
we need so if you're talking about
someone going there for a few months
um so back up a little bit
there are many things that make mars not
hospitable
temperature you can't breathe air you
need a pressure suit
even if you're on the surface the
radiation environment is you know even
in all those things the radiation
environment is too harsh for the human
body
um all of those things seem like they
could eventually have
technological solutions
the challenge the the real
significant challenge to me seems to be
the the creation
of a self-sustaining civilization there
you know you
can bring pressure suits you can bring
oxygen to breathe but those are all in
limited supply and if we're going to
colonize it we need to find
ways to make use of the resources that
are there to do things like
produce food produce the air the humans
need to keep breathing just in order to
make it self-sustaining there's a
tremendous amount of work that has to be
done
and people are working on these problems
but
i think that's going to be a major
obstacle in going from
visiting where we can bring everything
we need to survive in the short term to
actually colonizing
yeah i find that whole project
of the human species quite inspiring
these like huge
moonshot projects somebody i was reading
something um in terms of the source of
food that's that may be the most
effective on mars
is you could farm insects that's the
easiest thing to farm
so would be eating like cockroaches
if we're living on mars because that's
the easiest thing to actually
um as a source of protein so growing a
source of protein is the easiest thing
is
as insects i just imagine this giant
for people who are afraid of insects
this is not a pleasant
maybe you're not supposed to even think
of it that way it'll be like a cockroach
milkshake or something like that
right i wonder if have people been
working on the genetic engineering of
of insects to make them more radiation
friendly
right or pressure resistant or whatever
it makes them
what can possibly go wrong cockroaches
make them radiation resistant
they're already like survived all
everything plus i um
i took an allergy test i'm in austin so
there's everybody's alert is like the
allergy levels are super high there
uh and one of the things apparently i'm
not allergic to any insects
except cockroaches it's hilarious so
maybe uh um well
i'm gonna use that as you know people
use an excuse that i'm allergic to cats
to not have cats i'm gonna use that as
an excuse to uh
not go to mars as one of the first batch
of people otherwise i was gonna ask if
you had the opportunity would you go
yeah i'm joking about the cockroach
thing and i would definitely go
i love challenges i love i love things
i love doing things where the
possibility of death
is is uh not insignificant
because it makes me appreciate it more
meditating on death makes me appreciate
life
and uh when the meditation on death is
forced on you because of how difficult
the task is
i enjoy those kinds of things most
people don't it seems like
but i love the idea of difficult
journeys
for no purpose whatsoever except
exploration
going into the unknown seeing what the
limits of the human mind and the human
body are it's like what the hell else is
this whole journey that we're on for
i i uh but it could be because i grew up
in the soviet union there's a kind of
love
for space like the the space race the
cold war created
i don't know if still it permeates
american culture as much
but especially with the dad as a
scientist
i think i've i've loved the idea of
humans striving
out towards the stars always like from
the engineering perspective
has been really exciting i don't know if
people love that as much in america
anymore i think
elon is bringing that back a little bit
that excitement about rockets and
going out there but uh so that's that's
hopeful but for me i always loved that
idea
from uh alien scientist perspective if
you were to look
back on earth
is there something interesting you could
say about earth like how would you
summarize earth
like in a report you know like uh
hitchhiker's guide to the galaxy
like if you had to report like write a
paper on earth
or like a letter like a like a one pager
um summarizing the contents of the
surface and the atmosphere is there is
there something interesting
like do you ever take that kind of
perspective on it
i know you like volcanism so volcanoes
that will probably be in the report
and i was gonna say that's where i was
gonna go first uh there are a few things
to say about the atmosphere but in terms
of the volcano so
one of the really interesting
puzzles to me in planetary sciences
so we can we can look out there and
we've been talking about surfaces and
volcanoes and atmospheres and things
like that
but that is just you know this tiny
little veneer on the outside of the
planet and most of the planet is
completely sort of inaccessible to
telescopes or to spacecraft missions you
can drill a meter into the surface but
you know that's still really the veneer
um and one of the cool puzzles is
looking at what's going on
on the surface and trying to figure out
what's happening
underneath or just any kind of indirect
means that you have to study the
interior because you can't
dig into it directly even on earth you
can't dig deep into earth
so from that perspective looking at
earth
one thing that you would be able to tell
from orbit given enough time
is that earth has tectonic plates so you
would see
that volcanoes follow the edges if you
trace where all the volcanoes are on
earth they follow these
lines that trace the edges of the plates
and similarly you would see
things like the hawaiian string of
volcanoes that
you could infer just like you know we
did
as people actually living on earth that
the plates are moving over some plume
that's coming up through the mantle
and so you could use that to say if the
aliens could look at where the volcanoes
are
are happening on earth and say something
about the fact that earth has plate
tectonics which makes it really unique
in the solar system okay so the other
plants don't have
it's the only one that has plate
tectonics yeah what about io
and the the friction and all that that's
not play tech what's the difference
between
so oh it's plate tectonics like another
layer of like
solid rock that moves around and there's
cracks
yeah so so earth has plates of solid
rock
sitting on top of a partially molten
layer and those plates are kind of
shifting around on io
it doesn't have that and the volcanism
is what we call heat pipe
volcanism it's the magma just punches a
hole through the crust and comes out on
the surface i mean that's a
simplification but that's effectively
what's happening
through the freezing cold crust yes very
cold
very rigid crust yeah how do you how
does that look like by the way
i don't think we've mentioned so the gas
that's expelled
like if we were to look at it does it
look beautiful does it look boring
the gas like the whole thing like the
the magma punching through
oh my gosh i see yes i'm sure it would
be beautiful and the pictures we've seen
of it are beautiful
you have so the the magma will come out
of
the lava will come out of these fissures
and
you have these curtains of lava that are
maybe even a kilometer high so if you
looked at videos
i don't know how many volcano videos
you've looked at on earth but you
sometimes see a tiny tiny version of
this in iceland you see just these
sheets of magma coming out of a fissure
when you have this really low viscosity
magma sort of water-like
coming out at these sheets and the
plumes that come out
because there's no atmosphere all the
plume
molecules are just plume particles
where they end up is is just a function
of the
direction that they left the vent so
they're all following ballistic
trajectories
um and you end up with these umbrella
plumes you don't get these sort of
complicated plumes that you have on
earth
that are occurring because of how that
material is interacting with the
atmosphere that's there
you just have these huge umbrellas and
it's been hypothesized actually that
the atmosphere is made of sulfur dioxide
and
that you could have these kind of ash
particles from the volcano and the
sulfur dioxide
would condense onto these particles and
you'd have sulfur dioxide snow coming
out of these volcanic plumes
and uh there's not much light though
right
so you wouldn't be able to like it would
make a good it would not make a good
instagram photo because you have to
would you see the snow sure there's
light
it depends okay so you could you could
still okay it depends what angle you're
looking at it where the sun is all the
things like that
you know the sunlight is much weaker but
it's still there it's still there
and uh how big is io in terms of gravity
is is it smaller is it a pretty small
moon
it's quite a bit smaller than earth
anyway it's smaller than earth okay
okay cool so they float out for a little
bit so it floats well then yeah
no you're right that would be that would
be that'll be gorgeous
um yeah what else about earth
is interesting besides volcanic so plate
tectonics and i didn't realize that that
was the unique
element of a planet in the solar system
because that i wonder what i mean we
experience it as human beings it's quite
painful because of earthquakes and all
those kinds of things but
i wonder if there's nice features to it
yeah so coming back to habitability
again
um things like tectonics and plate
tectonics
are are thought to play an important
role in the surface being habitable and
that's because
you have a way of recycling material so
if you have a stagnant surface
everything you know you use up all the
free oxygen everything reacts until you
no longer have
reactants that life can extract energy
from
and so if nothing's changing on your
surface you kind of reach this
stagnation point
um but something like plate tectonics
recycles material you bring up new fresh
material from the interior you bring
down
material that's up on the surface and
and that can
kind of refresh your your nutrient
supply in a sense or the the sort of raw
materials that the surface has to work
with
so um from a kind of astrobiologist's
perspective looking at earth you would
see
that recycling of material because the
plate tectonics you would also see
how much oxygen is in earth's atmosphere
and between those two things you would
identify earth as a
reasonable candidate for a habitable
environment
in addition to of course the you know
pleasant temperature and liquid water
um but the abundance of oxygen and the
the plate tectonics both
play a role as well and also see like
tiny dot satellites flying around
well sure yes i wonder if they would be
able to i really think about that like
if they if aliens were to
visit and would they really see humans
as the thing they should be focusing on
i think it would take a while right
because it's so obvious that that should
because there's like so much incredible
in terms of biomass humans are a tiny
tiny tiny fraction
there's like ants they would probably
detect ants
right or they probably would focus on
the water and the fish
because there's like a lot of water i
don't i was surprised to learn that
there's more species
on land than there is in the sea like
there's 90
i think 90 to 95 percent of the species
are on
or on land on land not in the sea not in
the sea
i i thought like there's so much going
on in the sea but no the
the variety that like the branches
created by evolution
apparently it's probably a good answer
from evolutionary biology perspective
why
land created so much diversity but it
did so like the sea
there's so much not known about the sea
about the oceans but
it's not um it's not diversity friendly
what can i say he's uh it needs to he
needs to improve his diversity
what can you do do you think the aliens
would come i mean the first thing they
would see is
i suppose our cities assuming that they
had some idea of what a natural world
looked like they would see cities and
say these don't belong
which of these many species created
these yeah i mean there's
i if i were to guess it would
it's a good question i don't know if you
do this when you look at the telescope
whether you look at
uh geometric shapes like
if it's uh good because to me like
hard corners like what do we think is
engineered
things that are like have kind of
straight lines and corners and so on
they will probably detect those in terms
of buildings would stand out to them
because that's that goes against the
basic natural
physics of the world but
i don't know if the electricity and
lights and so on it could be i
honestly it could be the plate tectonics
it could be like that uh the like the
volcanoes that'd be okay that's the
source of heat and then they would focus
they might literally i mean depending on
how alien life forms are
they might notice the microorganisms
before they notice the big like notice
the ant before the elephant
because like there's a lot more of them
depending what they're measuring device
we think like size matters but maybe
with their tools of measurement they
would look for
quantity versus size like why focus on
the big thing
focus on the thing that there's a lot of
and when they see humans depending on
their measurement devices they might see
we're made up of billions of organisms
like the fact that we have we're very
human centered we think
we're one organism but that may not be
the case
they might see in fact they might also
see like a human city
as one organism like what is this thing
that like
clearly this organism gets um
aroused at night because the lights go
on
and then uh and then it like it sleeps
during the day
i don't know how like what perspective
you take on the city
is there something interesting about
earth or other planets in terms of
weather patterns
so we talked a lot about volcanic
patterns is there something else about
weather
that's interesting like storms or
variations in temperature
all those kinds of things
yeah so there's sort of every
planet and moon has a kind of
interesting and unique weather pattern
and those weather patterns are really
we don't have a good understanding of
them we don't even have a good
understanding of the
the global circulation patterns
of many of these atmospheres why the
storm systems occur
so the the
composition and occurrence of storms and
clouds and these objects is another one
of these
kind of windows into the interior that i
was talking about with surfaces one of
these
ways that we can get perspective and
what the composition is of the interior
and
how the circulation is working so
circulation will
bring some species up from deeper in the
atmosphere of the planet to some
altitude that's a little bit colder and
that species will condense out and form
a cloud at that altitude
and we can detect in some cases what
those clouds are composed of
and looking at where those occur
can tell you how the circulation cells
are whether
the atmospheric circulation is say
coming up at the equator and going down
at the poles
or whether you have multiple cells in
the atmosphere and
i mean jupiter's atmosphere is is
just insane there's so much going on you
look at these pictures and there's all
these vortices and anti-vortices and you
have these different bands that are
moving in
in opposite directions that may be
giving you
information about the the deep
proper like deep in the atmosphere um
physically deep properties
of um jupiter's
interior and in circulation
what are the these vortices wha what's
the basic material of the storms
it's condensed molecules from the
atmosphere so ammonia ice particles
um in the case of jupiter it's methane
ice in the case of let's say
uranus and neptune and other species you
can kind of construct
a chemical model for which species can
condense where and so you see a cloud at
a certain
altitude within the atmosphere and you
can make a guess at what that cloud is
made of
and sometimes measure it directly and
you know different species make
different colors as well
oh cool ice storms okay
i mean the climate of uranus has always
been fascinating to me because
it orbits on its side and it has a
42-year orbital period and so
you know with earth our seasons are
because our equator is tipped just a
little bit to the plane that we orbit in
so sometimes the sun lights a little bit
above the equator and sometimes it's a
little bit below the equator
but on uranus it's like for for 10 years
the sunlight is directly on the north
pole and then it's directly on the
equator and then it's directly on the
south pole
and it's it's actually kind of amazing
that the atmosphere doesn't look crazier
than
it does but understanding how taking
again like one of these extreme examples
if we can understand
why that atmosphere behaves in the way
it does
it's kind of a test of our our
understanding of how
how atmospheres so like heats up one
side
of the planet for 10 years and then
freezes it the next like
and that you're saying would should
probably lead to some chaos
and it doesn't the fact that it doesn't
tells you something about the atmosphere
so atmospheres have a property that
surfaces don't have which is that they
can redistribute heat a lot more
effectively right
so they're a stabilizing like
self-regulating
aspect to them that they're able to deal
with extreme conditions
but predicting how that complex system
unrolls is is very difficult as we know
about predicting the weather on earth
even
oh my goodness yeah the little variation
we have on earth you know people have
tried to
put together global circulation models
so you know we've done this for earth
people have tried to do these for other
planets as well
and it is a really hard problem um
so titan for example like i said it's
it's one of the best studied atmospheres
in the solar system and people have
tried to make these global circulation
models and actually predict what's going
to
to happen moving into sort of the next
season of titan and those predictions
have ended up being wrong and so then
you know
i i don't know it's always exciting when
a prediction is wrong because it means
that
there's something more to learn like
your theory wasn't sufficient
and then you get to go back and learn
something by how you have to modify the
theory to make it fit
excited by the possibility of one day
there'll be for various moons and
planets there'll be uh
like news programs reporting the weather
with the fake confidence of
like as if you can predict the weather
uh we talked quite a bit about plants
and moons can we talk
a little bit about asteroids for sure
what is uh what's an asteroid
and what kind of asteroids are there so
the asteroids
let's talk about just the restricted to
the main asteroid belt which is the
region
it's a region of debris basically
between
mars and jupiter and
the these sort of belts of debris
throughout the solar system the outer
solar system
you know the kuiper belt that we talked
about the asteroid belt as well as
certain other populations where they
accumulate because they're
gravitationally more favored
our remnant objects from the origin of
the solar system and so one of the
reasons
that we are so interested in them aside
from potentially the fact that they
could come hit earth but
scientifically it's
um it gives us a window into
understanding the
composition uh of the material from
which earth and the other plant is
formed
and how that material was kind of
redistributed over the
the history of the solar system so the
asteroids
one could classify them in two different
ways some of them are ancient objects so
they accreted
out of the the sort of disk of material
that the whole solar system formed out
of um and have kind of
remained ever since more or less the
same
um they've probably collided with each
other and we see the all these
collisional fragments and you can
actually
look and um based on their orbits say
you know like these 50 objects
originated as the same object
you can see them kind of dynamically
moving apart after some big collision
um and so some of them are these ancient
objects maybe that have undergone
collisions and then
there's this other category of object
that is the one that i personally find
really interesting which is um
[Music]
remnants of objects that could have been
planets so
early on a bunch of potential planets
secreted that we call
planetesimals and they formed and they
formed with a lot of energy and they had
enough time to actually differentiate so
some of these objects differentiated
into cores and mantles and crests
and then they were subsequently
disrupted in these
massive collisions and they now we have
these
fragments we think fragments floating
around the asteroid belt that are like
bits of mantle bits of core bits of
crust basically
um so it's like puzzle pieces you might
be able to stitch together
or i guess it's it's all uh
it's all mixed up so you can't stitch
together the original planet
candidates or is that possible to try to
see if they kind of
i mean there's too many there's too many
objects in there too i think that there
are cases where people have
have kind of looked at objects and by
looking at their orbits they say these
objects should have originated together
but they have very different
compositions and so then you can
hypothesize maybe they were different
fragments of a differentiated object
but one of the really cool things about
this is you know we've been talking
about
getting clues into the interiors of
planets
we've never seen a planetary core or
deep mantle
directly some mantle material comes up
on earth's surface and then we can see
it but
you know in sort of in bulk um
we haven't seen these things directly
and these asteroids potentially give us
a chance to like
look at what our own core and mantle is
like or at least
would be like if it had been also
floating through space for a few billion
years and
and getting irradiated and all that uh
but it's
it's a cool potential window or like
analogy into the interior of our own
planet
well how do you begin studying some of
these asteroids
what uh if you were to put together a
study like what are the interesting
questions to ask
that a little bit more specific do you
find a favorite
asteroid that could be tracked and try
to try to track it through telescopes
or do you uh is it has to be
you have to land on those things to
study it
so when it comes to the asteroids
there's so many of them and the big
pictures or the the big questions
are answered
um so some questions can be answered by
zooming in in detail on individual
object but mostly you're trying to do a
statistical study so you want to look at
thousands of objects even hundreds of
thousands of objects
and figure out what their composition is
and look at you know how many
big asteroids there are of this
composition versus how many small
asteroids of this other composition and
put together these kind of
statistical properties of the asteroid
belt and those properties can be
directly compared with the results of
simulations for the the formation of the
solar system
what do we know about the surfaces of
asteroids or the con
the the contents of the insides of
asteroids
and what are still open questions so
i would say that we don't know a whole
lot about their
compositions um most of them are small
and so you can't study them in such
detail with
telescopes as as you could you know a
planet or moon
and at the same time because there are
so many of them you could send a
spacecraft to a few
uh but you can't really like get a
statistical survey
with spacecraft and so a lot of
what we a lot of what has been done
comes down to sort of classification you
look at
how bright they are you look at uh
whether
they're red or blue simply you know
whether their spectrum is sloped towards
long wavelengths or short wavelengths
there are certain uh if you if you
point a spectrograph at their surfaces
there are certain features you can see
so you can tell that some of them have
silicates on them
um and but these are the sort of
they're pretty basic questions we're
still trying to classify them based on
fairly basic information in kind of
combination with our general
understanding of
the material the solar system formed
from and so you're sort of you can't
you're coming in with prior knowledge
which is that you more or less know what
the materials are the solar system
formed from and then you're trying to
classify them into these categories
there's still
a huge amount of room for for
understanding them better
um and for understanding how their
surfaces are changing
in the space environment is it hard to
land on an asteroid
is this uh is this a dumb question it
feels like uh
it would be quite difficult
to actually operate a spacecraft
in such a uh dense field of debris
oh the asteroid belt um there's a ton of
material there but it's actually not
that dense it is mostly open space
okay uh so so mentally do picture like
mostly open space with
with some rocks uh the problem is some
of them are not
thought to be solid so some of these
asteroids especially these these core
mantle fragments you can think of as
sort of solid like a planet
but some of them are just kind of
aggregates of
material we call them rubble piles and
so there's not necessarily
might look like a rock but do a lot of
them have kind of
clouds around them like a dust cloud
thing
or like do you know what you're stepping
on when you try to land on it
like what are we supposed to be
visualizing here this is like very few
have water right
there's some water in the outer part of
the asteroid belt but they're not
quite like comets okay um
in the in the sense of having clouds
around them there are some crazy
asteroids that do become active like
comets that's the whole other
category of thing that we don't
understand um
but they're surfaces i mean we have
visited some you can
you know find pictures that spacecraft
have taken of them we've actually
scooped up material
off of the surface of some of these
objects we're bringing it back
to analyze it in the lab um and there's
a mission that's launching
next year to land on one of these
supposedly
core fragment objects to try to figure
out what the heck
it is and what's going on with it but
the surfaces
you know they're they're you can picture
a solid surface with some little grains
of sand
or pebbles on it and occasional boulders
maybe some fine dusty regions dust kind
of collecting in certain places
but is is there does do you worry about
this is there any chance
that one of these fellas destroys all of
human civilization
by um an asteroid kind of
colliding with something changing his
trajectory and heading its way towards
earth
that is definitely possible and it
doesn't even
have to necessarily collide and change
its trajectory
we're not tracking all of them we can't
track all of them yet you know they're
still
a lot of them people are people are
tracking a lot of them and we are doing
our best to track more of them but there
are a lot of them out there
and it would be potentially catastrophic
if one of them
impacted earth um have you are you aware
of this um
apophis object so there's an asteroid a
near-earth
object called apophis that people
thought had a decent probability of
hitting
earth in 2029 and then potentially again
in 2036 so they did a lot of studies
it's not actually going to hit earth
but it is going to come very close
it's going to be visible in the sky and
a relatively dark
i mean not even that dark probably not
visible from los
angeles but um
and it's gonna come a tenth of
the way between the earth and the moon
it's going to come closer
apparently than some geosynchronous
communication satellites
oh wow so that is a close call
but people have studied it and then
apparently you're very confident it's
not actually going to hit us but it was
gonna have to look
into this because i i'm very sure i'm
very sure what's gonna happen
if an asteroid actually hits earth
that the scientific community
and government will confidently say
that we have nothing to worry about it's
going to be a close call
and then last minute they'd be like
there was a miscalculation
they're not lying it's just like the
space of possibilities
because it's very difficult to track
these kinds of things and there's a lot
of kind of
there's complexities involved in this
there's a lot of uncertainties
i just something tells me that
human civilization will end with we'll
see it coming
and then last minute there will be uh
oops
well like we'll see it coming and we'll
be like no it's this is
this is threatening but no problem no
problem and last minute it would be like
oops that was a miscalculation
and then it's all over in a matter of
like a week
uh is we're just very positive and
optimistic today
is there any chance that bruce willis
can save us
in the sense that from what you know
about asteroids is there something that
um
you can catch them early enough to uh
change volcanic eruptions right
sort of drill put a nuclear weapon
inside and
break up the asteroid or change its
trajectory
there is potential for that if you catch
it early enough
in advance i think
in theory if you knew
five years in advance ibm um
depending on the object and how close
how much you would need to deflect it
um you could deflect it a little bit
i don't know that it would be sufficient
in all cases
um and this is definitely not my
specific area of expertise but
my understanding is that there is
something you could do
but it also how you would carry that out
depends a lot
on the properties of the asteroid if
it's a solid object versus a rubble pile
so let's say you planted some bomb
in the middle of it and it blew up but
it was just kind of a pile of material
anyway and then that material comes back
together and then you kind of just have
the same thing
presumably its trajectory would be
altered but
it's it's like terminator 2 when it's
like the thing that's just like
you shoot it and splashes and then comes
back together will be very useless
that's fascinating and what's
fascinating
i've gotten a lot of hope
from watching uh spacex rockets that
land
there's so much it's like oh wow from my
ai perspective from a robotics
perspective
that wow we can do a hell of an amazing
job
with control
and but then we have an
understanding about surfaces here on
earth we can map up a lot of things
i wonder if we can do that some kind of
detail
of being able to have that same level of
precision
in landing on surfaces with as wide of
a variety as asteroids have so be able
to understand
the exact properties of the surface and
be able to
encode that into whatever rocket that
lands sufficiently to i presume
humans unlike them unlike the movies
humans would likely get in the way like
it should all be done by robots
and like land drill place the
the explosive that should all be done to
control
the robots and then you should be able
to dynamically adjust to um
to the surface the flip side of that for
a robotics person
i don't know if you've seen these it's
been very heartbreaking
uh somebody i know well russ tedrick at
mit led the darpa robotics challenge
team
uh for the humanoid robot challenge for
darpa i don't know if you've seen videos
of robots on two feet falling
but you're talking about millions you
know several years of work from with
some of the most brilliant roboticists
in the world
millions of dollars and the final thing
is a highlight video on youtube of
robots falling
but they had a lot of trouble with
uneven surfaces that's basically you
have to do
the challenge involves you're mostly
autonomous with some
partial human communication but that
human communication is broken up
like you don't get a you get a noisy
channel so you can
humans can which is very similar to what
it would be
like in humans remotely operating a
thing
on an asteroid and so with that robots
really struggle
there's some hilarious painful videos of
like a robot
not able to like open the door and then
it tries to open the door without like
misses the handle and in doing so like
falls
it's um it's painful to watch so
like that there's that and then there's
spacex so i have hope from spacex
and then i have less hope from bipeda
robotics
but it's fun it's fun to kind of imagine
and i think the planetary
side of it comes into play in
understanding the surfaces of these
asteroids more and more
that you know forget sort of destruction
of human civilization
it'd be cool to have like spacecraft
just landing on all these asteroids to
study them
at scale and being able to figure out
dynamically
what you know whether it's a rubble pile
or whether it's
a solid objects do you see that kind of
future of science
maybe 100 200 300 years from now where
there's just
robots expanding out through the solar
system like
sensors essentially some of it taking
pictures from a distance some of them
landing just exploring and giving us
data
because it feels like we're working with
very little data right now
sure i i do see exploration going
that way i think um
[Music]
the way that nasa's currently
or historically has been doing missions
is putting together these these really
large
missions that do a lot of things that
are extremely well tested and have a
very low rate of failure but
now that these sort of cubesat
technologies are are becoming easier to
build easier to launch
they're they're very cheap and you know
nasa is getting involved in this as well
there's there's
a lot of interest in these missions that
are relatively small
relatively cheap and just do one thing
so you can really optimize it to
just do this one thing and maybe you
could build 100 of them and send them to
different asteroids and they would just
collect this one piece of information
from each asteroid
it's a kind of different more
distributed way of doing science i guess
um and there's a ton of potential there
i agree
let me ask you about objects or one
particular object from
outside our solar system we don't get to
study many of these right
they don't we don't get stuff that just
flies in out of nowhere
from outside the solar system and flies
through apparently there's been two
recently in the past few years one of
them
is amor more what are your thoughts
about
amor more so fun to say
could it could it be space junk from a
distant alien civilization or is it just
a weird shaped comet
i like the way that's freezed um so
umua is is a fascinating object just the
fact that we have started discovering
things
that are coming in from outside our
solar system is amazing
uh and can can start to study them and
now that we have seen
some we can
design now kind of thinking in advance
the next time we see one we will be much
more ready for it we will know which
telescopes we want to point at it we
will have explored whether we could even
launch a fast turnaround mission to
actually like get to it before it leaves
the solar system
um in terms of a muammua yeah it's
for an object in our solar system it's
really unusual
in two particular ways
one is the dimensions that we don't see
natural things in our solar system that
are
kind of long and skinny we see the
things we see in our solar system don't
deviate from spherical by
that much um and then that it showed
these strange properties
of accelerating as it was leaving the
solar system which was not understood at
first
so in terms of the
alien space junk you know as a scientist
i cannot rule out that possibility i
have no
evidence to the contrary um
however so you're saying there's a
chance
i cannot i cannot as a scientist
honestly say that i can rule out
that it's alien space junk however i i
see
the kind of alien explanation
as following this uh the sagan's
extraordinary claims
require extraordinary evidence if you
are going to actually claim that
something is
aliens um you need to carefully evaluate
one needs to carefully evaluate the
other options and see whether
it could just be something that we know
exists that makes sense
in the case of a muammua
there are explanations that fit well
within
our our understanding of how things work
so there are a couple
there are two hypotheses for what it
could be made of they're both
both basically just ice shards in one
case it's a nitrogen ice shard that came
off of something like pluto in another
solar system
that pluto got hit with something and
broke up into pieces and one of those
pieces came through our solar system
in the other scenario it's a bit of a
failed solar system so our solar system
formed out of a
collapsing molecular cloud sometimes
those molecular clouds are not massive
enough
and they sort of collapse into bits but
they don't actually form a solar system
but you end up with these kind of chunks
of hydrogen ice apparently
and so one of those chunks of hydrogen
ice could have got ejected and passed
through our solar system
so both cases explain
these properties in about the same way
so
those ices will sublimate once they've
passed the sun and so as they're moving
away from the sun you have the hydrogen
or nitrogen ice sublimating off
the sunward part of it and so that is
responsible for the acceleration
the shape also because you have all this
ice sublimating off the surface
uh if you take something the the analogy
that um
works pretty well here is for a bar of
soap your bar of soap
starts out sort of close to spherical at
least from a physicist's perspective
and as you use it over time you
eventually end up with this long thin
shard because it's been just by sort of
weathering
as we would call it um
[Music]
and so in the same way if you just
sublimate material off of one of these
ice shards it ends up
long and thin and it ends up
accelerating out of the solar system
and so given that these properties can
be reasonably well explained that way
um you know we should be
extremely skeptical about attributing
things to
yeah aliens see the reason i like to
think that it's aliens
is because it puts a lot of priority on
us not being lazy
and we need to catch this thing next
time it comes around
i like the idea that there's objects not
like i
it's almost saddens me they they come
out of the darkness
really fast they just fly by and go and
leave
it just seems like a wasted opportunity
not to study them
it's like uh it's the easiest ways to do
space travel outside of the solar system
it's having the things come to us
right i like that way of putting it and
like it would be nice to just
land on it like and first of all
really importantly detect it early yes
and then land on it
like with a really nice
like spacecraft and study the hell out
of it
and you know i because
yeah it uh if there's a chance it's
aliens
alien life it just feels like
such a cheap way inexpensive way
to get information about alien life or
something
interesting that's out there and i'm not
sure if a nice shard from another
planetary system will be interesting but
it very well could be
it could be totally new sets of
materials it could be to tell us about
composition of
of planets we don't quite understand
and it's just nice one especially in the
case of a momoi i guess it was pretty
close to earth
it would have been nice to uh to uh you
know it's like
don't go there they come to us i don't
know that's what makes me
uh that that's what makes me quite a sad
it's a missed opportunity
well yeah and whether whether you think
it's aliens or not it's
it's a missed opportunity but you know
we weren't prepared and we will be
prepared for
the next ones and um as
so there's been a movement in astronomy
more towards what's called time domain
astronomy so kind of monitoring
the whole sky all the time at all
wavelengths that's kind of the goal and
so we expect to detect
many more of these in the future even
though these were the first two we saw
our potential to detect them is only
increasing with time and so there will
be more
opportunities and you know based on
these two we now can
actually sit and think about what we'll
do when the next one shows up
i also what it made me realize i i know
i didn't
really think through this but it made me
realize if there is alien civilizations
out there
the thing we're most likely to see first
would be space junk
my stupid understanding of it
the second would be really dumb kind of
you could think of maybe like relay
nodes or something objects
that you need to have a whole lot of
for particular purposes of like space
travel and so on
like uh speed limit signs or something i
don't know whatever we have on earth a
lot of
that's dumb it's not alien aliens in
themselves
it's like artifacts that are useful to
the engineering
in the systems that are engineered by
alien civilizations so like
it would we would see a lot of stuff
in terms of setting in terms of looking
for alien life and trying to communicate
with it
maybe we should be looking not for like
smart creatures
or systems to communicate with maybe we
should be
looking for artifacts or even as dumb as
like space junk it just kind of reframed
my
perspective of like what are we looking
for as signs
is there there could be a lot of stuff
that doesn't have intelligence but gives
us really strong
signs that there's somewhere is life or
intelligent life
and um yeah that made me kind of
i know it might be dumb to say but
reframe the kind of thing that we should
be looking for
yeah it's so the the benefit of looking
for intelligent life is that we perhaps
have a better chance of recognizing it
um yeah we couldn't necessarily
recognize what an alien stop sign look
like
um that's true and maybe you know the
the theorists are
the people who sort of model and try to
understand solar system objects are
are pretty good at coming up with models
for anything i mean if maybe umua was a
stop sign
but we're clever enough that we could
come up with
some physical explanations for it and
then you know we all want to go with the
simplest possible
we all want to believe the sort of most
skeptical uh possible explanation and so
we missed it because we're too good at
coming up with alternate explanations
for things and it's such an outlier such
a rare phenomenon that we can't
we can't study you know a hundred or a
thousand of these objects we have
we had just one and so the science
almost destroys uh
the possibility of something special
being there it's like a
uh johnny ive this designer of apple i
don't know if you know who that is he's
the lead designer he's the
person who designed the iphone and all
the major things
and he talked about he's brilliant one
of my favorite humans on earth
and one of the best designers in the
history of earth
he talked about like when he had this
origins of an idea
like in his baby stages he would not
tell steve jobs because steve would
usually like trample all over it he
would say this is dumb idea
and so i sometimes think of the
scientific community in that sense
because
the the weapon of the scientific method
is so strong
at its best that it sometimes crushes
the
out of the box outlier evidence
you know we don't get a lot of that
evidence because we don't have um
we're not lucky enough to have a lot of
evidence so we have to deal with just
special cases and special cases could
present an inkling of something much
bigger
but the scientific method user tramples
all over and it's hard to know what to
do
with that because the scientific method
works
but at the same time every once in a
while it's like a balance
you have to do 99 of the time you have
to do like scientific rigor
but every once in a while this is not
you saying me saying
smoke some weed and sit back and think
i wonder you know it's the joe rogan
thing it's entirely possible
that it's alien space junk
anyway yeah i think so i i completely
agree and i think that
most scientists do speculate about these
things
it's just at what point do you act on
those things
um so you're right that the scientific
method has inherent skepticism and
for the most part that's a good thing
because it means that we're not just
believing
crazy things all the time but
it's an interesting point that
requiring that high level of of rigor
occasionally means that you will miss
something that is
truly interesting because you needed to
verify it
three times and it wasn't verifiable i
also think like when you communicate
with the general public
i think there's power in that one
percent speculation
of just demonstrating authenticity as a
human being as a curious human being
i think too often the i think this is
changing
but uh i saw i've been quite
disappointed my colleagues throughout
2020 with the
with with the coronavirus there's too
much speaking from authority
as opposed to speaking from curiosity
there's some of the most incredible
science has been done in 2020 especially
on the virology biology side
and the kind of being talked down to by
scientists is always really
disappointing to me
as opposed to inspiring like the things
we there's a lot of uncertainty about
the coronavirus
but we know a lot of stuff and we speak
from
scientists from various disciplines
speak from data
in the face of that uncertainty and
we're curious we don't know what the
hell is going on we don't know if this
virus is going
to evolve evolve mutate we don't know if
this virus or the next one
might you know might destroy all human
civilization you can't speak with
certain
in fact i you know i was on a on a
survey paper about masks
something i don't talk much about
because i don't like politics
but we don't know if masks work but
there's a lot of evidence to show that
they work for this particular
the transmission of the virus is
fascinating actually the
the biomechanics of the way viruses
spread
is fascinating it if it wasn't
destructive
it would be beautiful and we don't know
but it's it's inspiring to to apply the
scientific message
to the best of our ability but also to
show that you don't always know
everything
and to and perhaps not about the virus
as much but
other things speculate what if you know
what what if it's uh the worst case and
the best case
and um because that's ultimately what we
are descendants of apes that are just
curious about the world around us
yeah i uh i'll just add to that not on
the topic of masks but on the topic of
curiosity that's
um i mean i think that's
astronomy and planetary sciences a field
are
a little are are unique because for
better and
for worse they don't directly impact
humanity
so you know we're not studying virology
to
to prevent transmission of um
you know illness amongst humans we're
not
characterizing volcanoes on earth that
could destroy cities we and it really is
a more curious and in my opinion playful
scientific field than many um
yeah so for better and worse we can kind
of afford to pursue some of the
speculation more because
human lives are not in danger if we
speculate a little bit too freely
and get something wrong yeah definitely
in the space of ai i am worried that
we're sometimes too eager
speaking for myself to uh like flip
the switch to on just to see like what
happens uh maybe sometimes we want to be
a little bit careful about that
because uh bad things might happen
is there books or movies in your life
long ago
or recently that um that were inspiring
had an impact on you that you would
recommend
yeah absolutely uh so many that i just
don't know where to start
with it um so i i love reading i read
obsessively i've been reading
fiction and a little bit of non-fiction
but mostly fiction
obsessively since i was a child and just
never stopped
um so i have some favorite books
none of them are easy reading so i
definitely i mean i recommend them for
somebody who likes an intellectual
challenge
in the books that they read um
so maybe i should go chronologically i
have at least
three i'm not going to go through 50
here
but yeah i'd love to also like uh
maybe ideas that you took away from sure
as you mentioned
yeah yeah why they were so compelling to
me um
one of the first books that really
captured my fascination
was nabakov's book pale fire oh wow
um are you familiar with it so
i read it actually for a class it's one
of the few books i've ever read for a
class that i actually really liked
and the book is
it's in some sense a puzzle he's a
brilliant writer of course
um but the book is like it's it's
formatted like a poem so there's an
introduction
a very long poem and footnotes
and you get part way through it before
realizing that the whole thing is
actually
a novel unless you sort of read up on it
going in but
but the whole thing is a novel and
there's a story that
slowly reveals itself over the course of
all of this
and kind of reveals this
just fascinating character basically and
how how his mind works in this story
the idea of a novel also being a kind of
intellectual
puzzle and something that slowly reveals
itself over the course of reading
was really fascinating to me and i have
since found a lot more
writers like that you know
contemporary example that comes to mind
is kazuo ishiguro who's pretty much
all of his books are like slow reveals
over the course of the book and like
nothing much
happens in the books but you keep
reading them because you just want to
know like what the reality is that he's
slowly revealing to you
the kind of discovery oriented reading
maybe
what's the second one perhaps my
favorite writer is
rainier
you're hitting hidden ones i mean i know
in the bulk of well but
now i've never read pale fire but really
i've never
i know it's a very difficult read i know
that much
yeah right all of these are difficult
reads i think i just
i read for in part for an intellectual
challenge
but relka so he wrote
one thing that might be characterizable
as a novel but he wrote a lot of poetry
i mean he wrote this series of poems
called the duino elegies that were very
impactful for me personally just
emotionally
um which actually it kind of ties in
with astronomy um
in that there's there's a sense
you know in which we're all going
through our lives alone and there's just
this sense of kind of profound
loneliness in the existence of every
individual human and i think
i was drawn to astronomy in part because
the sort of vast spaces the kind of
loneliness and desolateness of
of space made the sort of internal
loneliness feel okay
in a sense it like gave companionship
and
um i that's how i feel about roelka's
poetry he turns the kind of
desolation and loneliness of human
existence into something
joyful and almost meaningful
yeah there's something about melancholy
i don't know about rookie in general but
like contemplating the
the melancholy nature of our of the
human condition
that makes it okay
like i gentle from an engineering
perspective think that there is
so much loneliness we haven't explored
within ourselves yet
and that's my hope is to build ai
systems that help us explore our own
loneliness
i think that's kind of what love is and
friendship is
is somebody who in a very small way
helps us
explore our own loneliness like they
listen
we connect like two lonely creatures
connect for a time
that's like oh like acknowledge that we
exist
together like for a brief time
but in a somewhat shallow way i think
relative to how much
it's possible to truly connect those two
consciousnesses so
ai might be able to help on that on that
front
uh so what's the third one actually you
know i hadn't realized until this moment
but it's yet another one of these kind
of slow reveal
books um it's a contemporary
uh russian i think russian-american
writer named
olga grisham g-r-u-s-h-i-n
and she wrote this just phenomenal book
called the dream life of sukhinov
that i read this year maybe it was last
year for the first time
and it's just a really beautiful
this one you could call a character
study i think
of a russian father coming to terms with
himself and his own past um
as he potentially slowly loses his mind
slow reveal slow reveal
well that's apparent from the beginning
i hope i don't think it's a spoiler
decline into madness spoiler alert so
all of these are really heavy i don't
know i just
i don't have anything lighter to
recommend ishiguro's the light version
of this okay um well heavy is
has a certain kind of beauty to it in
itself is there advice you would give to
a young person today
that looks up to the stars and wonders
what the heck they want to do with their
life
so career science life in general
you've uh for now chosen a certain kind
of path of curiosity
what uh what insights do you draw from
that you can give us advice to others
i think for somebody i i would not
presume to speak
to giving people advice on on life and
humanity overall but for somebody
thinking of
being a scientist so there are a couple
of things
one sort of practical thing which is
career-wise i hadn't appreciated this
going into science but
you need to so
the the questions you're working on and
the techniques you use
are both of very high importance maybe
equal importance for being happy in your
career
if there are questions you're interested
in but the techniques that you need to
use to do them
are tedious for you then your job is
going to be miserable
even if the questions are inspiring so
you have to find but if the techniques
that you use
are things that excite you then your job
is fun every day
so for me i'm fascinated by the solar
system and i love
telescopes and i love doing data
analysis playing with data from
telescopes coming up with new ways to
use telescopes and so that's where i
have found that
mesh but if i was interested in you know
the dynamical evolution of the solar
system how the orbits of things evolve
then i would need to do a different
type of work that i would just not find
as appealing and so it just wouldn't be
a good fit and so
it sort of is seems like an unromantic
thing to have to think about the
techniques being the thing you want to
work on also but it really makes
a profound difference for i think your
happiness and your
scientific career i think that's really
profound it's like the thing
the menial tasks if you enjoy those
that's a really good sign that
that's the right path for you i think
david foster wallace said that uh the
key to life is to be unborable
so basically everything should be
exciting
i don't think that's feasible but you
should find an area where
everything is exciting i mean depending
on the day
but you could find the joy in everything
not just the big exciting
chronicle things that everyone thinks is
exciting but the
the details the the repetitive stuff the
medial stuff the stuff that takes years
this
stuff that involves a lot of failure and
all those kinds of things that you find
that enjoyable that's that's actually
really profound to focus on that
uh because people talk about like dreams
and passion and goals and so on the big
thing
but that's not actually what takes you
there it takes you there's every single
day
putting in the hours and that's what
actually makes up life
is the boring bits and if the boring
bits aren't boring and that's an
exciting life
let me uh because when you were talking
so romantically and passionately about
io
i remember the the poem by robert frost
so let me ask you uh let me read the
poem and ask
what your opinion is that's called fire
and ice oh
yeah i could almost recite this from
memory some say the world will end in
fire some saying ice
from what i've tasted of desire hold
with those who favor fire
but if i had to perish twice i think i
know enough of hate
to say that for destruction ice is also
great
and will suffice so uh let me ask
if you had to only choose one would you
choose the world to end in fire
in volcanic eruptions in heat
and magma or in ice
frozen over fire ice
fire
excellent choice the sort of
i i've always been a fan of chaos and
uh the idea of things
just slowly getting cold and stopping
and dying is just so depressing
to me so much more depressing than
things
blowing up or you know burning or
getting covered by a lava flow somehow
the like activity of it
endows it with more like meaning to me
maybe
some i've just now had this vision of
you you know in action films where
you're walking away without looking back
and there's explosions behind you
and you just got and you put on like
shades and then it goes to credits so
um katherine this was awesome i think
your work is really
inspiring the
the kind of things we'll discover about
planets in the next few decades is super
cool and i hope
i know you said there's probably not
life in one of them but there might be
and i i hope we discover just that and
um
perhaps even on io within the volcanic
eruptions there's a
there's a little creature hanging on
that we'll one day discover
thank you so much for wasting all your
valuable time with me today it was
really it was really awesome
yeah likewise thank you for having me
here
thanks for listening to this
conversation with catherine declare and
thank you to
fundrise blinkist expressvpn
and magicspoon check them out in the
description to support this podcast
and now let me leave you with some words
from carl sagan
on titan the molecules that have been
raining down like mana from heaven
for the last four billion years might
still be there
largely unaltered deep frozen awaiting
for the chemists from earth
thank you for listening and hope to see
you next time