In war, the 'high ground' refers to the most strategic position available on a battlefield,
and its occupation and exploitation gives the force occupying it major military advantages.
With the dawn of the space age, it quickly became clear that the space around earth was
the ultimate high ground, and whoever conquered it first would put all other militaries at
a severe disadvantage.
So why hasn't it happened yet?
That’s what we’ll find out today, in this episode of The Infographics Show- why we can't
put weapons on space stations.
The first and most obvious answer is a simple matter of physics.
Newton's Third Law of Motion states that for every action there is an equal, and opposite
reaction.
If you throw a ball, the ball pushes back on you- but the friction between your feet
and the ground keeps you in place.
If you were to try throwing a ball on roller skates though, the force of the ball pushing
back on you would knock you backwards.
Because space is a vacuum, there is no friction- so basic physics tells us that if you tried
to shoot a rocket or fire a big enough gun from a space station, you would send that
space station flying out of control.
You would have to either counteract the force of the firing weapon with reaction control
thrusters, or make a station massive enough that the force pushing back on the station
is minimal- though of course you would still need to adjust your orbit after every shot
to make sure you didn't accidentally de-orbit your entire space station!
With an average cost of putting objects or fuel into orbit resting at $1 million dollars
per pound, either option makes for a very, very expensive weapon.
Gun are pretty much out of the question, but you could potentially design a missile that's
gently released with just a small puff of accelerant before its rocket motor ignites
and carries it away- similar to how the International Space Station undocks visiting spacecraft.
So why not do that?
Well, basic physics is again the most obvious answer- a missile re-entering the earth's
atmosphere would experience the same extreme heating that a returning space capsule does.
In order to protect the chemical warhead from accidentally blowing up, you would have to
spend a lot of money on shielding materials to keep the warhead cool during re-entry.
Ultimately it's just not worth it- conventional land, air and sea-fired missiles are much
cheaper and less risky.
But there is one type of missile that would be worth the cost, risk, and difficulty of
firing from orbit- a nuclear-tipped missile.
The goal of a nuclear arsenal is not just to respond to a nuclear attack- but ideally
to be able to destroy an enemy's own nuclear arsenal before they have a chance to retaliate.
With nuclear weapons, speed is key- yet even at a whopping 4 miles per second, an ICBM
launched from Russia at the United States would still need about 41 minutes to reach
the East Coast.
If we put nuclear weapons in orbit though, that flight time would potentially shrink
to mere minutes.
The International Space Station (or ISS) orbits the earth at 5 miles per second, making a
complete orbit in just 92 minutes.
If a nation where to build a constellation of just six nuclear-armed orbital stations
at the same altitude as the ISS - 250 miles above earth- there would always be one station
loaded with nuclear weapons flying over enemy territory, and the next station with its nuclear
payload would be a maximum of 15 minutes away.
Most nuclear nations operate a nuclear launch and detection system made up of a small fleet
of satellites that are constantly scanning the earth for the telltale massive heat signature
of an ICBM being fired.
Once detected, other satellites and ground tracking stations use radar to track the ICBM.
But a nuclear-tipped missile fired from orbit wouldn't need a big rocket motor - instead
each missile could simply be released, use small RCS thrusters like those used on space
capsules when docking to orient each missile to a different target, and then let gravity
pull them down to earth.
Without a big, very hot rocket motor, an early warning and detection system would be useless,
and outfitting a missile with radar absorbent materials like those used on modern stealth
aircraft would make radar tracking extremely difficult.
Basically, a nation could launch a crippling sneak attack against another nation, decimating
its nuclear stockpiles and ICBM launch complexes, and fifteen minutes later have another salvo
ready to fire as a new orbital station moves into position overhead.
So why- especially during the heated rivalry of the Cold War- hasn't any nation done this?
The official reason is the UN's Outer Space Treaty.
Ratified on October 1st, 1967, by 107 countries- including China, the United States, and the
Soviet Union- the treaty served as the basic legal framework upon which international space
laws could be built upon.
With the space race in full swing and humanity's imagination picturing a near-future of space
colonies and interplanetary travel, it became clear to the UN that space itself would soon
have to be regulated much the same way we regulated the open seas with international
maritime laws.
Much more pressing though than a need for basic laws governing the use of space, was
the reality of potential conflict between two very hostile nuclear powers- the Soviet
Union and the United States.
MAD- or Mutually Assured Destruction- had for the moment maintained the peace and kept
either nation from even flirting with the possibility of nuclear war, as each nation
knew it could never survive a retaliatory strike.
But with space technologies and capabilities rapidly evolving in both nations, the possibility
of one nation putting nuclear weapons into space and thus circumventing the safeguards
of the MAD doctrine became very real.
Thus while the Outer Space Treaty governs the use of space and prohibits nations from
claiming sovereignty over any moon, planet, or anything in between, the main goal of the
treaty was to ban the use of nuclear weapons in space and thus maintain the security of
the MAD doctrine.
This is the legal reason why no nation has ever tried to put weapons into space- but
the Outer Space Treaty only governs weapons of mass destruction, and while as we saw before
missiles or guns would do very little good in space, other weapons known as kinetic impactors
would be extremely effective.
Basically nothing more than a very large and very dense projectile, a kinetic impactor
uses only its own mass, velocity and kinetic energy to deliver incredible devastation.
The impactor has no chemical explosive, and relies on fundamental physics - because Force
= Mass times Acceleration, by dropping something very massive (or dense) from orbit and letting
the force of gravity accelerate it to thousands of miles an hour as it falls, you could potentially
deliver a destructive blast on par with a small, tactical nuclear weapon.
In fact, the US military has used similar weapons before in both the Korean and Vietnam
war.
Known as 'Lazy Dog' bombs, the projectiles were nothing more than 2 inch-long pieces
of steel outfitted with fins.
When dropped from an aircraft, the projectiles would reach 500 miles an hour and be capable
of penetrating 9 inches of solid concrete - not bad for having absolutely no explosive!
So why then has no nation put kinetic impactor weapons in space?
The reason, it turns out, is a matter of simple self-preservation.
If any nation began such a program, every other nation on earth would face three choices:
A) Allow that nation to complete its orbital weapon system program and be at their mercy
forever. B)
Begin their own orbital weapon system program.
C) Immediately go to war with that nation before they can complete building their orbital
weapon system.
In order to avoid all-out war, or risk creating an environment where even if it fields its
own orbital weapons, a nation is still critically vulnerable to hostile orbital weapons it cannot
possibly counter, the United States, Russia, and other space-faring nations have, to date,
simply refused to build these weapons.
In the best case scenario, putting orbital weapons in space would simply force other
nations to do the same, creating yet another Mutually Assured Destruction scenario.
Given how many close calls we've had already with our earthbound nuclear arsenals, it's
ultimately best we simply stay away from putting any weapons in
space- period.
But, what do you think though?
Should nations have the right to put anything they want in space?
Let us know your thoughts in the comments!
Also, be sure to check out our other video called What Happens When You Get Knocked Out!
Thanks for watching, and, as always, don’t forget to like, share, and subscribe.
See you next time!