Kind: captions
Language: en
this is the biggest most ambitious most
expensive video I've ever made and it's
also going to be terrifying
we are strapping these giant metal
weights to the belly of that helicopter
flying it up several kilometers in the
sky and then dropping these weights
on a sand castle City
I mean we need a lot
and this is all for a very good reason
so let's do it come on
[Music]
in the late 1950s the United States had
a problem the Soviet Union launched the
first artificial satellite Sputnik into
orbit around the Earth on the 4th of
October 1957.
but less well-known is that just over a
month earlier they successfully tested
the first intercontinental ballistic
missile or ICBM
it could deliver a nuclear warhead from
the Soviet Union to cities on the U.S
east coast in around 30 minutes
facing this threat a researcher at
Boeing named Jerry Purnell came up with
an idea for a space weapon it could hit
any location on Earth in half that time
just 15 minutes it could destroy targets
buried 30 meters underground like the
silos where the Soviet nukes were kept
and theoretically it could intercept
icbm's mid-flight
[Music]
his concept was to put telephone
pole-sized pieces of tungsten in space
in orbit
so that these pieces of tungsten could
drop on a Target basically at any time
the idea was within a 15 minute window
you would be able to release one of
these tungsten rods and have it re-enter
the atmosphere and strike a Target in
minutes
and it would come in so fast you know in
orbit things go about eight kilometers
per second and as it enters the
atmosphere it's going to slow down due
to the atmospheric drag but still on
impact it's still going to be going like
10 times the speed of sound mach 10 or
about three kilometers per second
this is Moab which stands for Massive
Ordnance Air Blast but it's more
commonly referred to by its nickname the
mother of all bombs
it is one of the most powerful
non-nuclear explosives on the planet
when it detonated it released the
equivalent of 11 tons of TNT now just
one of these tungsten rods coming in
would have the same energy as the
largest conventional explosive ever
detonated
they are not bombs they contain no
explosives but the amount of energy that
they're carrying in their kinetic energy
because they are so heavy and they're
going so fast it is as big as any
conventional bomb ever detonated
Purnell called his weapon project Thor
after the Norse god who threw lightning
bolts from the heavens in the 1980s the
kinetic missile Interceptor idea was
seriously considered by the Reagan
Administration it was codenamed
brilliant Pebbles but the project was
abandoned in 2003 it was resurrected by
the Air Force transformation plan which
referred to this weapon as hyper
velocity Rod bundles but colloquially
the weapon is known as rods from God
the kinetic energy of an object is
directly proportional to its mass and
its velocity squared so increasing the
object's Mass 10 times increases its
kinetic energy 10 times but if you
increase the velocity by a factor of 10
the kinetic energy Grows by a factor of
a hundred this is why even very light
objects can carry lots of kinetic energy
this is what a 15 gram piece of plastic
does to a block of aluminum when
traveling at six kilometers per second
and this is a real problem for
satellites because of the massive speeds
on orbit micrometeorites small bolts or
even flecks of paint are serious risks
for the astronauts living on board the
International Space Station
this chip in the window of the ISS was
caused by a tiny Speck of dust and a
small piece of space junk punctured a
hole in the robotic arm imagine
something that weighs 10 tons traveling
that fast
kinetic energy weapons appear in fiction
including dozens of movies video games
and books but how realistic are they I
mean could this weapon ever become a
reality
well that's why we're here in the middle
of the desert we want to see how
damaging a rod from God could be and we
really pulled out all the stops even
hiring a team of professional Sandcastle
Builders to construct a city onto which
we'll drop the rods
I have all the respect in the world
these Sandcastle bullies
[Music]
we are seven-time U.S open Sandcastle
Champions that's so cool
[Music]
it'll endure the test of the highest
weight of the highest drop with very
little damage I'm really convinced of
that
the U.S Capitol was great yeah isn't
that great yeah I love all the buildings
there who did the pickle the gherkins
yeah the gherkin right here very nice
this is beautiful I mean I feel bad for
trying to trying to hit it
I am just very concerned about aiming
the city is not that big so before we
get to that drop we're gonna try to hit
this swimming pool with a 100 kilogram
or a 220 pound Mass uh probably go up
about 500 meters try to drop a weight
right into this pool
I don't think it's gonna work I don't
think we're gonna hit it in fact my main
concern for the whole day is that we're
just not going to be able to hit
anything and then what was the point
coming out here in the first place
these are going to be the questions that
I asked myself
so the way we're targeting is with GPS
we're going to take a GPS mark from like
the center of the pool oh boy we've also
got GPS in the helicopter
we're gonna use that to try to line up
Square over the middle of the pool
so if we're able to hit this pool from
500 meters then I think we've got a shot
[Music]
okay where's your GPS my GPS is my phone
and I have the coordinates written on my
arm we're ready to go we're
professionals
foreign
first drop
and it's feeling shaky I gotta tell you
got another 700 feet to be at uh 1500
okay
I just don't know
like why they're circling up that high
is that 500 meters that seems really
high
[Music]
1500 feet that seems higher than 1500
feet
that is freaking crazy okay here we go
this is the one this is the one
[Music]
it's swinging around like crazy up there
yeah does it have fins on it Jesus no no
fins why didn't we have this
conversation a week ago
looking good we're good left or right
that's good we just need to go forward
oh geez that does not like look like
they're in position right are you
kidding me never will
[Music]
oh my
what the what is that gonna hit
oh it is going sideways
what did it hit
me
oh geez that was way more often I
thought
we both said we were right on it and we
weren't
it didn't look like you guys were moving
but yeah he he's telling me our
horizontal velocity was zero and you
were in the right spot we were exactly
in the right spot
oh wow
oh wow look at that
oh wow totally totally buried falling
from 500 meters the rod accelerated for
10 seconds and even accounting for air
resistance it hit the ground going about
350 kilometers per hour at that speed
with a mass of 100 kilograms it was
carrying nearly half a million joules of
kinetic energy
our plan for the day is to drop
something twice as heavy from six times
higher
then its energy on impact will be
greater than the explosion of a kilogram
of TNT
kinetic impacts are explosive
if you look at the craters on the moon
and you look really closely you're going
to see that they're basically all
circles
I think no one stops to ask why are they
circular if you imagine when the moon
gets hit by asteroids they're going to
come in from all different directions so
shouldn't you get these sort of oblong
shapes where the asteroid comes in
well the truth is the asteroids come in
with such incredible speed that it's not
like they're pushing dirt out of the way
and that's what creates the crater no
they're coming in so fast that when they
Collide their kinetic energy is
explosive it heats up the ground turns
things into liquid and gas they all get
super hot and they spray outwards in a
giant explosion and this explosion is
symmetric it doesn't matter which angle
or how shallow the asteroid was coming
in it's gonna blow out everything
radially because it is explosive kinetic
energy is explosive and I think for me
that's just the really surprising thing
it would be the exact same thing with
dropping these rods going mach 10 when
they hit a Target they're going to
create an explosion as though they are
the largest conventional weapon ever
launched and because it's going so fast
it can penetrate around 30 meters of
soil enough to bust bunkers or silos and
the explosion is therefore more
localized so it can be used for precise
surgical strikes plus unlike a nuclear
weapon there's no radioactive fallout to
worry about or International laws
do these ideas contravene any current
laws or treaties
no the only International agreement
there is about putting weapons in space
is about nuclear weapons the only real
prohibition is is about putting nuclear
weapons in space
yeah man like I thought targets would be
hard to hit
now I'm like super convinced they're
impossible
what we're gonna do now we're gonna do a
much lower altitude and we're gonna do
it visually yeah so we're gonna do it
you know 300 feet visually I'm gonna do
a cube drop a cube drop is interesting
because I was like we shouldn't do a
cube drop we're here talking about rods
of God they're cylinders right now I'm
so thankful we have the cubes because
the cylinders as uh Adam Savage told me
cylinders tend to fall on their sides if
given enough chance really who would
have thought I would have thought like
you know a pencil type thing it would it
would tend to aim straight down
that still looks High
is that 100 meters because that
30 second call it doesn't look like
they're over the pool
it's totally blowing around in the Wind
is totally swinging
spot on
still feels High
we're on it we're running
all right that wasn't far off
we're off by 60 feet oh wow did you look
like we were right above it look like it
yeah wow
as I showed we're right on it as well
that's something from 100 meters
I'll take it
okay we're setting up to drop this Mass
200 kilograms 440 pounds
what do you think
This Is The Moment of Truth we've had
two misses so far
so we're going 50 meters or 150 feet
above the pool which for me
it's pretty disappointing but at this
point I just want to hit something
oh boy the weight is swinging around on
there
it's getting blown around by the wind
I mean we need luck
[Music]
there it goes there goes there it goes
I'm tracking tracking
oh
it hit something yes
it's like right on the edge right on the
edge
this morning I was so worried that we
weren't gonna hit anything and like I
think the footage is just so shaky
because I was so excited but like seeing
that from above was amazing
wow it ripped right through the pool
unbelievable rubber duckies sir is the
next Target the sand castle and you want
to go for 100 meters I want to double it
this will be amazing if we can actually
hit the sand castle from 100 meters
that'll be something
in all the different incarnations of
rods from God the rods are made out of
tungsten and there are two reasons for
this the first is that tungsten is
really really dense a cubic meter of
tungsten weighs 19 tons that's over
twice the density of Steel which is what
we're using here just because it's a lot
cheaper but that means for a given
amount of mass tungsten rods could be
less than half the volume of Steel and
therefore encounter less resistance as
they pass through the atmosphere
and importantly for re-entry tungsten
also has an incredibly high melting
point the highest of any metal at almost
three and a half thousand degrees
Celsius this is important because as the
rod decelerates through the atmosphere a
lot of heat builds up all around it and
tungsten's high melting point means the
rods require much less shielding to
prevent them from melting
the shape is also important the goal is
to hit the target with as much speed as
possible so a Sleek aerodynamic shape is
best and rods are a great shape for that
aerodynamics is why arrows and bullets
and ballistic missiles all look the way
they do it's to minimize drag
honestly one of the big mistakes we made
was not welding fins onto our rods
we're going up to about 100 meters
for 300 feet
drop we're going to hit the sand castle
City that's the goal
there it goes there it goes there goes
it's going
did it hit in front Justin and just in
front
we just missed it
we are close we're really close so the
tractor's gonna dig the weight out right
now just pick it up go
that's how it landed so close to taking
out the capital yeah look at that
30 seconds to drop
20 seconds that wind is brutal
oh boy oh boy oh boy
uh hit something on the left but I don't
think it was the city
seeing all the challenges we're going
through reminds me just how difficult it
is to aim a kinetic projectile 10
seconds
there it goes
did they hit a building
yeah
what
what what
I cannot believe it
direct hit on the building
but it only took down that side
I find it unbelievable
look at the cracks in the back and like
it created cracks but it didn't make
them didn't destroy the whole building
this is not what you would use if you
wanted to cause Mass Devastation this is
like if you wanted to to pinpoint a
Target
now if I'm honest we did not manage to
make a fair test of rods from God even
on a small scale you know I wanted to
drop 200 kilograms from three kilometers
but aiming was so hard that we got
nowhere near that so we didn't get to
see the explosive power of kinetic
energy when we made one last-ditch
attempt to drop again from 500 meters I
was just terrified that we were gonna
hit something or someone
look out look out look out look out look
out oh
yeah
oh
I was just happy to finish the day with
everyone safe I didn't
I didn't see it
wow
you're right that it bounced out
but given the amount of time and money
we spent on this video I would say it is
my biggest failure of all time which as
it turns out is also something you could
say about the actual weapon rods from
God I mean just start with aiming
steering a rod from God is in theory
possible you could use thrusters or
adjustable fins or change the Rod's
Center of mass but in practice it's
incredibly difficult to aim an object
traveling at Hypersonic speeds
not only that communicating with the rod
from the ground or from space would be
nearly impossible due to the superheated
plasma surrounding it and there are
other problems you know say you want to
hit a Target within 15 minutes you'd
think the simplest thing would be to put
a rod right above the Target in
geostationary orbit but geostationary
orbit is over 35
000 kilometers away that's almost a
tenth the distance to the Moon so from
there a rod would take several hours to
fall to the Earth
and if you put it in low earth orbit say
around 350 kilometers above the Earth
the rod will move relative to the ground
doing a revolution around the Earth
every 90 minutes so between ordering a
strike and the rod hitting the Target
that could take anywhere up to an hour
and a half
you might think that you could get that
time down to about 30 minutes by placing
say 10 satellites in that orbit but
remember the Earth rotates so orbits
drift you would actually need hundreds
of satellites to make sure there's
always a rod close by the Target so
let's say you want to put a hundred rods
into space well the cost of launching
them will be billions of dollars and
over time the thrusters will break down
and malfunction so there are going to be
ongoing maintenance costs
but what if you just want to use it for
missile defense well then you don't need
something that weighs 10 tons a smaller
Rod would do but even then it's really
really tricky and to successfully
intercept an ICBM you've got to hit it
during the Boost phase modern icbms
split into a number of payloads after
the Boost some of which are decoys to
overwhelm anti-icbm defense missiles to
stop North Korean ICBM launches for
example the US would need around 400
rods spread among eight orbits to be
able to intercept missiles in time a
global defense system would require at
least a few times that amount and it's
been calculated that even a very limited
system would cost around 300 billion
dollars which is nearly half of the US
military annual budget and even that
wouldn't work because enemies could
evade the defense by launching several
missiles at the same time since there's
only one rod in the right location at
any time of Rod could intercept one of
the missiles but the rest would pass
through
so rods from God turns out to be
unfeasible to execute in reality after
his stint at Boeing Jerry Pernell who
came up with the idea became a science
fiction writer and in his 1985 New York
Times best-selling book footfall an
alien race uses kinetic weapons to
invade the Earth
and honestly I'm pretty glad that this
weapon is feasible only in science
fiction
foreign
is all about trying failing and
sometimes blowing stuff up and if you
can't drop giant steel rods in the
desert well then the next best thing is
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