Kind: captions
Language: en
greetings earthlings who are so tired of
being stuck at home
and hearing the same political headlines
over and over again
let's switch it all up and talk about
space
history making link up in orbit as the
spacex crew and the dragon today the
first round
of u.s space force enlistees graduated
right here in san antonio and there's a
piece of technology we all rely on
that's really shifted how we both
explore and exploit
space iran's revolutionary guard says
the country is now able to quote
monitor the world from space china says
it has sent the world's first 6g
experiment satellite into space south
korea's first military communications
satellite was launched
into space in california people living
near vandenberg air force base were
warned today about sonic booms
this falcon 9 rocket carried a satellite
into orbit that will monitor
sea levels what's lurking up there
in the sky satellites
extremely complex packages of
engineering that give us
almost limitless benefits like watching
tv tracking the weather finding our way
home
making calls around the world exploring
outer space
they basically deserve a really big
thank you for making our sheltered and
place lives
manageable there are about 6 000
satellites orbiting earth right now
and of those nearly half are still
operational just this year
humankind has launched hundreds of
satellites with flags from
every continent except antarctica maybe
that'll change i don't know what's up
penguins
and we even have more than a dozen
orbiting mars
mars so straight up we need to give you
the dish on satellites get it i'm funny
but for real
they're an integral part of our modern
world and help us understand our planet
and ourselves this is nova now
where we explore all the celestial far
out science behind the headlines
and this astronomical body we call
planet earth
i'm alok patel
you often hear the statement well humans
aren't big enough
or powerful enough to affect something
like the earth's atmosphere or
the land surface and yet you can look at
the record and see
that transition occurring through land
use and urbanization and so forth
jeffrey g massik who goes by jeff is a
project scientist for landsat
9 at nasa's goddard space flight center
i think
when we look at that we realize that
we're a lot more powerful than we think
we are
in our ability to change the environment
the landsat program is a collaboration
between the u.s geological survey and
nasa
in 1972 a satellite was launched which
will help to manage
world agriculture landsat beginning with
landsat 1
the program's launched a total of eight
satellites since the early 70s
providing the longest continuous
space-based record of the surface of the
earth
we acquire imagery of aldera's land and
coastal areas
every eight days so we've assembled this
long record
of how the planet has changed and that's
designed to support
land management decisions by governments
at
state local national level and
individuals as well
so we have five decades of right
information and you know knowledge about
our planet from outer space
can you tell us a little bit about what
we've learned about
our lovely blue planet from space in
general what we've
seen just graphically is how dynamic the
planet
is in response to human activities when
you
grow up in an area you know your
neighborhood for example you don't
really notice the changes that occur
over years and decades right this just
kind of almost seems constant but when
you
run the the movie in fast motion
suddenly you see all of these changes
and the urbanization and the changes in
forest management and all of that right
i mean we see areas where
agriculture suddenly goes in irrigated
agriculture into desert environments for
example
and then we see it fade away again we
see areas that convert from forests to
soybean
fields big areas in south america i
think one of the recent
real big accomplishments the program has
been looking at
ice sheet velocity tracking so
when you look at antarctica or greenland
and how they're changing response to
climate warming
with landsat data you're basically able
to track features on the surface and and
create a
velocity map for the ice sheets and
people are doing that year in year out
now which is
pretty fascinating okay so speaking of
all these landsat images
i'm going to look at them in real time
i'm on climate.nasa.gov i'm going to
compare landsat images of greenland
glaciers
from 1972 to 2019 here we go
so off the bat it already looks like
there's
less glacier if you compare the two
pictures i see more of the brown earth
more of these like rocky peaks and this
other picture it looks like the glacier
is
almost like not present like it's it's
retreated away in this other picture
there's water where there probably
shouldn't be like the glacier has melted
if that sounds like climate change it's
because it is
25 status check go atlas go centaur
go ldcm today two of the landsat
satellites are still orbiting our planet
landsat 7 since 1999 and landsat 8 that
was launched in an atlas 5 rocket from
vandenberg air force base in california
in 2013. five four
three two one zero
at ignition and liftoff of the atlas v
rocket on the landsat data continuity
mission
continuing the 40-year legacy of
deserving earth's natural resources from
space
landsat 9 is the next mission it's got
souped-up sensors and is scheduled for
launch next year
eventually it'll replace landsat 7 which
is nearing the end of its life
let's zoom out for a sec you know take
an astronaut's view
maybe a matt damon from the martian's
view a satellite is an
object in space that orbits around
another object
there's natural satellites like our moon
and artificial satellites like the
international space station
both orbit the earth artificial
satellites can be operated by
governments the military commercial
companies and places like universities
or research centers
they can be classified by their purpose
there's communication satellites like
the att t16
the latest in a fleet that's supporting
the direct tv satellite television
service
there are military defense satellites
those are also often imaging satellites
geostationary operational environmental
satellites that help meteorologists
observe and predict
local weather events space science
satellites for research
earth observation satellites like
landsat and of course
gps is huge gps i love gps
do you know what it actually stands for
it's global positioning system
a navigation system that's made up of 30
satellites
as of now everybody knows gps gives you
your location on your cell phone
and that is a satellite constellation
that the us operates
for anyone out there who disrespects
satellites i would like you to remember
the days when we used to try to drive
places
without our phones stopping in gas
stations and asking people which
direction
you know is what city with the paper map
atlas right
yeah yeah satellites were first imagined
by such visionaries as sci-fi
writer arthur c clarke who in 1945
suggested if you launched an object with
enough velocity
it could fall into orbit around the
planet
it would be the soviets who would place
the first human-made satellite into a
low earth orbit in 1957
sputnik 1 a 23-inch metal ball that
carried a thermometer
batteries and a radio transmitter to
space
these days satellites come in all shapes
and sizes
not just 23-inch metal balls there are
some now you know
very small cubesats that can fit in the
palm of your hand
the landsat satellites are larger they
tend to be sort of school bus sized or
minivan sized
the landsat satellites are remarkable
feats of engineering that allow us to
watch our planet it's basically an
imager
mounted on top of what we call a
satellite bus okay so the imagers are
the instruments like the camera
and the satellite bus provides the life
support for
everything that imager has to do so this
the power the solar
array the fuel for maneuvers
you know the antennas to bring the data
down can you tell us a little bit more
about the instruments
walk us through the technology and how
we get these incredible images from the
landscape satellites
so landsat images in a lot of different
spectral wavelengths so our eyes
see in the visible part of the
electromagnetic spectrum landsat goes
beyond that into the infrared
and into what we call this thermal
infrared so that's
basically looking at heat coming from
the earth
landsat 9 and landsat 8 have two
separate instruments on board
the operational land imager gets to the
shorter wavelengths the light comes from
the sun
it reflects off the surface of the earth
and it arrives at a telescope
that's on the instrument and basically
the light bounces around it gets focused
onto a focal plane
which converts the light into an
electrical signal which gives a measure
of the brightness of the earth's surface
the second one is called tears thermal
infrared sensor
is dedicated for the longer wavelengths
for the thermal infrared
so we can look at surface temperature
and instead of the light coming from the
sun
it's basically radiation that comes from
the surface temperature so it's emitted
radiation from the planet itself
you know corresponding to the surface
temperature that again goes up to the
instrument through a telescope and to
the detectors
this radiation is proportional to
earth's surface temperature
the data that the satellites image we
think of them as pictures but in fact
they're measurements of surface
reflectance
or surface temperature each satellite
positions itself to capture images in
direct sunlight once every 99 minutes
so about 14 times a day landsat uses a
705 kilometer
altitude orbit that's about 438 miles
above
me right now in my closet sound booth as
a landsat satellite travels from the
north pole to the south pole
it's capturing data over a 115 mile wide
swath
which means a full picture of our planet
is ready in a little bit more than 16
days
and then the cycle starts again now i
understand
satellites are designed with kind of a
lifetime in mind
oftentimes they can go beyond that
expectation
how do you know when a satellite has
kind of reached the end of its life and
then after that what happens to them do
they get a proper space burial
do we just leave them up there yeah so
usgs operates the satellites
monitors all of the systems on board and
so
what we find for example is you may be
running low on fuel
right and if you run out of fuel you
can't do the necessary maneuvers to keep
the satellite in the proper orbit
the gyros or reaction wheels may fail
in that case you have a hard time
maintaining the attitude of the
satellite and that's
considered dangerous because at that
point you're kind of an out of control
vehicle in the
in the orbit and you can run into other
things it's considered bad manners
so when you lose enough systems then
basically you make the determination to
deorbit the satellite
and you fire some thrusters you bring it
into a lower orbit
and you know there's various policies
for how fast you have to deorbit a
satellite but it's usually sort of
decades
it takes and you just let it reenter and
burn up
more recent satellites actually have to
be actively deorbited so that you
know what ground target you're going to
hit
when the satellite deorbits i often
think about
the movie gravity and space debris
potentially hitting something
you know do we worry about the size of
earth's orbit
and a potential time when it could get
too crowded
and those incidents could start
happening so space debris is a big
problem
and it's an operational problem for the
landsat satellites we're
on occasion having to move the satellite
out of the way of some piece of space
debris and that interrupts the imaging
cycle and so it's it's a hassle
okay so perhaps that movie gravity is a
little over hyped
but space junk is still an issue space
debris usually refers to human-made
particles and it's estimated that there
are more than 900
000 pieces of this stuff in orbit
ranging from about half an inch
to around 4 inches and there are natural
objects out there as well like meteors
and these can definitely be hazardous
but there's a much higher likelihood of
a collision with a human-made
object but in general when it starts to
get near the end of life we move it out
of the way that's the most important
thing you can do
what you find is is that certain orbits
are useful and certain orbits are not so
used
landsat is in a particular orbit called
a sun synchronous orbit where
every overpass is the same local time
uh for imaging so this the solar
illumination conditions are the same
for every image which is desirable there
are
other orbits just above or below it that
really aren't used very much and so
the trick is to move the satellite out
of an operational orbit into some other
orbit that's not used very much where
it'll be kind of
out of the way satellites can be grouped
together as they orbit
which works well when they have a shared
purpose in nasa we have something called
the a train for atmospheric observations
for example
which has several satellites that look
at the atmosphere all on a train
just like a line of cars in the same
lane on a highway
or a line of ducklings following their
mom as they're crossing that highway
they do have to worry about how close
they come and if there's
an avoidance maneuver because there's
some kind of debris coming toward
the first one then they all have to kind
of jump out of the way in a coordinated
fashion so that's a big part of
satellite maintenance
the landsat program is just one of the
many projects using satellites
in less than a hundred years the space
above us has become a place for
innovation
and contributions to society after the
break we'll meet someone who's thinking
of how space can help us
improve life down here on this blue
planet
we're at an exciting period in the space
journey where there's opportunities to
put more and more satellites in space
but yet we have to take care
so we don't create so much debris or
risk of collision in space
that we actually miss the chance to use
these space technologies for benefit on
earth
dr danielle wood is an assistant
professor at the mit media lab
she's also the director of the space
enabled research group remember the
possible
issues with space junk in 2019 the world
economic forum created
a transdisciplinary consortium that
includes space enabled
and teams from the european space agency
the university of texas at austin
and a company called bryce space and
technology they're working on the space
sustainability rating a new and
innovative way of addressing the orbital
challenge
so we're identifying actions that
companies can take
to earn a good rating that an operator
with satellite
can have a sustainable mission and for
us sustainability means
they're trying to avoid colliding with
other missions they're trying to avoid
being debris meaning leaving their
mission as trash and orbit for a long
time after they're finished
so we want to give basically a score to
any group from government or
companies or universities and to
celebrate those who are doing their best
to reduce debris what's interesting
though a lot of people want to go
basically to the same place in space
because
they're interested in operating for
similar activities and the physics means
that you might want to go
somewhere near another neighbor of yours
and is there an organization that kind
of centralizes the authorization
for satellites or is it just up to other
countries other
space programs to follow the rating
scale or to apply for it or to
you know pay attention to it so the
first thing you need to know is that
anytime
an object is launched to space every
satellite in every rocket is launched
by a country meaning it's under the
authority of a certain country
so it's very good that we already have
national laws
that review the plans for space missions
before they go to space
and each object that goes to space
whether it's a satellite or a rocket
or an instrument has been applied
to make sure they're following the
standards of that particular country so
on one hand
the space sustainability rating is not
trying to replace national regulations
or national processes of giving licenses
for satellites and rockets
what we are actually trying to do is
encourage arthritis of satellites to
even go beyond what's required by their
country
so we'll give even you know a better
score if a mission does better than
what's required by the law
the consortium is sharing the rating
system with countries around the world
so national governments can choose to
include it as one of the items they
consider
when deciding whether to approve the
launch of a new satellite
and when it starts the rating will be
voluntary
this work has some history behind it i
am very thankful
about what happened in the early years
of the space era danielle wood
is a scholar of societal development
with a background that includes
satellite design
earth science applications systems
engineering and technology policy
because this was also a period of the
cold war
and it was not obvious whether countries
would come together
to make a peaceful approach to working
in space or whether instead we would
actually
make worse some of the tensions that
were already in place between especially
the united states and the soviet union
we could have really seen space programs
lead to further aggressions and perhaps
even
another world war but instead we saw
countries come together
and identify the fact that space is
another global commons
just like we see with the oceans
antarctica places that
really belong to all humans equally not
in particular countries
in 1967 the outer space treaty was open
for signature
in the united states the united kingdom
and the russian federation
it provided the basic framework for
international space law
the outer space treaty establishes a key
principle which says that
space is the common heritage of all
humankind
and therefore it should not be a place
for one particular country or company
which be a place that we consider a
shared opportunity
so whoever is acting in space now is
really in a sense a steward of it for
those who might use in the future not
just
for their own current needs the treaty
was the first of five
organized by the united nations
committee on the peaceful uses of outer
space
and has now been signed by more than a
hundred countries from every region
including latin america and all over
africa and southeast asia and eastern
europe and
the caribbean so there really is a mix
of countries around the world helping to
shape
the current debates around space policy
and playing a role in deciding how and
where we operate in space
and under what conditions we do so and
when you think about the intersection
between space and justice there's kind
of three big questions
one is what has been the legacy how has
technology played a role in either
advancing or reducing justice
the second is what do we see today in
terms of today's space technology and is
it being used
uh sort of uniformly around the world to
serve people and make sure that they
have what they need from the benefits of
space
and the third is as we look to the
future and we expand have more people
living and working in space over the
long term
we want to ask what justice look like
for the kind of communities we're going
to create
so in my class in the fall i teach my
students to read
some key history from the last 500 years
and to really engage with the reality of
colonization
and slavery and mismanagement of power
by countries toward
other countries and by groups like
different racial groups to other groups
and we asked the question what have we
done wrong in our human history recently
that we should not carry forward into
space the anti-colonial view says
let me consider that what i do in a
global commons
a place that's shared by different
countries is not just up to my country
and my country's benefit but should be
done in a way that considers
future generations and asks what are the
concerns of other
stakeholders other countries other
indigenous groups that may have certain
views
i think that concept of people acting
in in researching space are stewards for
the future is an important one and i
really respect how you
frame space technology in a way that
should benefit everyone
and so you know i want to ask you if you
could give us some examples of
space technology that's been developed
that supports
and encourages sustainable development
on earth the united nations has an
excellent job curating sustainable
development goals
as an aspirational list of the ways we
all need to work together to change the
world
17 sustainable development goals are at
the heart of the un's 2030 agenda
for sustainable development that quote
provides a shared blueprint for peace
and prosperity for people in the planet
now and into the future they recognize
that ending poverty in other
deprivations
must go hand in hand with strategies
that improve health and education
reduce inequality and spur economic
growth
all while tackling climate change and
working to preserve our oceans and
forests
unquote mike drop now part of what my
team does is constantly ask
what are the ways that space technology
can be used
both to monitor the progress and to
actually manage make progress towards
the sdgs danielle wood's space enable
team has identified
different space technologies that can
support the sustainable development
goals
and a few in particular directly address
these goals with the help from
satellites for example communication
satellites can help with disaster
recovery
satellite positioning is helping track
endangered wildlife and earth
observation satellites can help us
tackle hunger
by allowing us to understand what areas
on the planet
are in danger of drought the space
enable team is even working to help
respond to the kovid 19 pandemic in
different parts of the world
[Music]
let's be real space technology has
shifted the way we see our planet
and ourselves what do you think
is going to be the future for space
technology
what do you want to see happen well
there's a lot of things happening now
that are really exciting
that again is jeff masic so the
commercial world has kind of
pioneered a model in which there are
constellations of small
satellites landsat 8 and landsat 9 are
pretty big
systems and they get all of their
imagery from one
large platform when you look at some of
the commercial companies out there
they don't necessarily have the
capabilities of landsat
in terms of the spectral bands they
acquire and the quality of the data
but they acquire a lot of data and they
do it by launching
fleets of small satellites in some cases
hundreds of cubesats
cubesats are very small cube-shaped
satellites
as the name suggests they come in
different sizes based on a standard unit
that's about
four inches long standardization helps
make them cheaper to produce
the idea was to help make space access
affordable for the university science
community
and now not only universities but high
schools middle schools even elementary
schools have been able to start their
own cubesat program
they've been used for all sorts of
things including remote sensing and
communications
that's a model that nasa is looking at i
don't think we can put landsat on a
cubesat just for technical reasons
but we are looking in the future at
constellation approaches where we sort
of
break up the mission into a series of
smaller satellites
because it's also more resilient right i
mean we could have a single point of
failure you know knock on wood
we don't have one but if we had a single
point of failure with landsat 9
we'd be kind of out of luck for several
years if you launch a constellation of
satellites and you have a single point
failure
you can live with it these expensive
satellites that people often think
of a lot of the actual cost is going
into the testing
and the review of the engineering over
and over before it's launched here again
is dr danielle wood
because if you have a big expensive
satellite that cost hundreds of millions
of dollars
you want to make sure that it's going to
work and work well for many years
if you're building a satellite that's
more like the size of a toaster and it
should last for less than a year and you
might
offer to have more of them after you
finish this one then you can spend less
time on the engineering on the testing
the design but you still want to make
sure you're using parts that make sense
and
and trying to get design as good as
possible but you also might have more
opportunities over this 10-year period
to keep trying new technologies rather
than sort of waiting 10 more years to
try the next generation
and technology keeps on advancing
landsat satellites today
can capture objects as small as 100 feet
on the ground
but future missions could provide even
higher resolution
um we don't have the resolution to look
at area 51 very well
um cool uh
there was a researcher at goddard who
was
using satellite data including landsat
to look at
penguin populations in antarctica
satellite images taken over the
antarctic show large
stained patches of sea ice identified as
the bird's guano
leading to the discovery of new breeding
sites and as the bbc's victoria gill
reports there are now thousands more
penguins than first quarter
that's awesome yeah i mean you know
and that's that is one cool thing about
landsat is
people are always finding new
applications right so it's it's not just
like one thing you do again and again
it's
there's always new stuff to find i love
that report penguin poop identified
exactly can't see the penguins but you
can see their poop
wait someone had to make it right
[Music]
you can download the landsat data for
free from the u.s geological survey
website
comb through it maybe you might discover
something if you do share it with jeff
nova now is a production of gbh and prx
it's produced by ian koss re daniel
jocelyn gonzalez isabel hibbard sandra
lopez mosalve
and christina monad julia court and
chris schmidt are the co-executive
producers of nova
dante graves as director of audience
development tsuki bennett is senior
digital editor
robin kasmer is science editor emma uk
is research intern
and nina porzuki is managing producer of
podcasts at gbh
our theme music is by the milky way's
best turntablist
dj kid koala i'm eloque patel
we'll be back in two weeks which is
plenty of time for you to look up
satellite names and pick out your
favorite maybe you can name your dog or
your child the satellite name
my favorite one is fun cube one but
shout out to aolus aerocube 8b
black sky pathfinder xiaoniang sky
brazil one taikon theos ursa major wild
blue one
za cube 2 canopus b hodo yoshi and
iridium are these satellites or
superheroes
and while we're all looking up in the
sky and looking at stars and the
thousands of satellites and maybe the
space debris i hope you're all staying
safe
and you have a very very happy holiday
season