Chicken apocalypse
They're mad about the vaccine thing so now we're all going to pay
To take their minds off all their friends who recently became McNuggets, the chickens rented G.I. Joe: Retaliation. When in a fowl mood1 chickens really like mindless violence. The movie has, quite unfortunately, given them an idea about how to avenge their fallen comrades - build a super weapon.
Megalomania is surprisingly common among chickens.
The scary death weapon in the movie involved something the chickens are calling the “egg from god” and is a long metal rod dropped from orbit. It picks up so much speed dropping to earth that it hits the ground with the energy of a nuclear weapon. According to the evil guy in the movie, “the rod touches down eight times faster than a bullet and with a force significantly greater than a nuclear warhead.”
Chickens are forbidden, by international law and The U.S. Department of Agriculture, from owing nuclear weapons. But Elon has a spaceship and they’re going to hijack it, simultaneously becoming the first chickens in space and a world-class military power.
Does this really work? Or have the chickens been smoking weed with Elon again?
The concept is called a kinetic energy (KE) weapon. The chickens have been excitedly pecking at their calculators ever since they got back, so let’s check their work.
Low earth orbit (LEO) is generally defined as anything up to 2,000 kilometers above the earth2. Something dropped from 2,000 km, falling at 1 g (the acceleration of the earth’s gravity, which is 9.8 m/s²) will hit the earth moving about 6,261 meters per second (3.9 miles per second or mach 18). This really is more than 8 times the speed of some bullets so movie guy wasn’t kidding about that part. It will also take more than five minutes to reach the ground but that was compressed in movie time.
The International Space Station sits in LEO at around 400 km but employs no chickens (who fixes their solar panels?). Hence the need to hijack the Falcon Heavy.
But can they get a nuclear-sized bang?
Some of the chickens used to be steely-eyed Air Force missile men and they know their nukes. The U.S. government has several (nukes, not chickens), and the little one is called the B61 nuclear bomb. It has a variable yield (adjustable bombs!) of up to 340 kilotons. The chickens tell me that converted to energy this is 1,422 terajoules (1,422,000,000,000,000 joules).
One joule is equal to one watt for one second. The Chicken House Solar Generating Plant has a 1 km² solar array and generates an average of 55 MW (megawatts) of energy. It would need 300 days of continuous operation (55,000,000 watts for 25,854,545 seconds, which is about 300 days) to generate this amount of energy. The Chicken House only has 1 km² of solar panels, but something the size of a big nuclear plant (4 gigawatts) could do this in about 4 days.
Kinetic energy is easy to calculate - it’s the mass of the egg (rod) times the square of the velocity, divided by two. [KE = 1/2 x Mass x Velocity²]
Since we already know the velocity (6,261 m/s) we can work out how big an egg we need to drop to get a 1,422 terajoule boom.
It’s one hell of an egg: it weighs 72,551,020 kilograms (80,000 tons) which is more than the Yamato3, the largest battleship ever built (which also employed zero chickens, despite their well-known skill at long range naval gunnery).
We’re calling it the MegaEgg. Elon already trademarked the term HyperEgg - and we’re afraid to ask why.
We don’t have orbital battleships and that might be for a reason. How much does it cost to put a battleship into LEO?
The cost of using a rocket to put something into space is often given in dollars per kg - the heavier the object, the more it will cost. Everyone with a spaceship is cagey about this number but the Russians do a lot of large payload launches and they charge something like $5,000 per kilogram4.
Elon is promising that his new super rocket will be much cheaper, less than half as much. We all know Elon likes to stretch the truth a bit, but let’s just take him at his word and say the Special Poultry Discount Rate is $1,500 per kilogram. Putting a single Yamato-sized egg into LEO will cost $108 billion dollars. Chickens are great at lots of things but have no concept of money so they think this is great.
For comparison, a coach class ticket to Des Moines is about $200 and the average adult human weighs less than 100 kg, so this is like $2 per kg. And you get snacks.
[Note: we’ve been ignoring the atmosphere to keep this simple. Most meteors burn up in the mesosphere5 which starts at about 85 km. At 6 kilometers per second the egg is only in atmosphere for a few seconds. This will slow down the MegaEgg, and we could use a bigger egg to compensate but it will cost even more to put into orbit.]
This whole thing works better if we put the egg into geosynchronous transfer orbit (GTO) instead, at 35,000 km. Now the egg weighs only 4,145,773 kg (slightly heavier then a current U.S. Navy frigate) and takes 22 minutes to reach the ground. But GTO is much more expensive per kg. Elon is claiming $4,0006 per kg and if take him at his word this is $16 billion per MegaEgg instead. That’s the price for Falcon Heavy, which hasn’t yet made a flight to GTO so decide how much you believe him. I suspect the $4,000 amount doesn’t really get us out to 35,000 km but whatever.
How about a smaller boom? If we go with LEO, and a much smaller boom (say, original Hiroshima A-bomb size) it comes in at a cool $4.8 billion each, but that’s only 5% of the B61 yield. The chickens were not impressed.
This sounds like a lot of money. We should discuss this with the chickens before they blow the whole budget.
The U.S. government is really tight-lipped about the cost of their nuclear weapons but everyone is losing their minds over the cost of the current B61 upgrade program7, with 400 being rebuilt for about $28 million each. These will have all sorts of nifty new features so the $28 mil might be on the high end, but I think you have already gotten the point. Everyone is flipping out over this $11.55 billion dollar program because it costs as much as an aircraft carrier, and one decent-sized MegaEgg can easily cost more than this whole program.
The whole “golden egg” thing is a myth, so the chickens aren’t getting this weapon - and neither is anyone else.
So are we safe? No death from the sky, fueled by righteous chicken rage?
Chicken anger is a cold, bitter anger and they’re not going to give up. They’ve all started studying Korean - they’ve been talking to someone they met in a chatroom for psychotic dictators and he can hook them up for a fraction of this cost. So be wary, and keep an eye on the hen house.
What was the point of all this insanity?
There actually was a point here. I recently heard some folks on a podcast talking about the silly weapon from the movie, and wondering if the government already has secretly built one (or more).
The answer, obviously, is no.
But the point is that we didn’t have to kidnap someone from the Pentagon and interrogate them to figure this out. We just had to assume it was technically feasible and do a little math - and find out that whether it’s feasible or not doesn’t really matter. Building just a few dozen of these weapons would cost hundreds of billions of dollars, even using the most optimistic set of assumptions possible. This would be the dumbest way possible to spend money on a weapon system8, and would be so expensive it would eat up the entire U.S. defense budget all by itself.
There are a lot of questions that can be approached this way, and we may use similar back-of-the-envelope calculations in the future to analyze real problems instead of deranged chicken fantasies.
Had to be done. Sorry.
https://www.sciencedirect.com/topics/engineering/low-earth-orbit
https://www.thoughtco.com/world-war-ii-battleship-yamato-2361234
https://aerospace.csis.org/data/space-launch-to-low-earth-orbit-how-much-does-it-cost/
https://www.nasa.gov/mission_pages/sunearth/science/atmosphere-layers2.html
https://www.universetoday.com/129989/saturn-v-vs-falcon-heavy/
https://ploughshares.org/issues-analysis/article/meet-budget-busting-b61-nuclear-bomb
Yet given how Pentagon procurement works, I also assume that once Lockheed Martin announces such a program it will be funded immediately.
I like the way you say 'we' when you summarise what you have worked out - as if it were remotely possible that I, as reader, had your skills and aptitude for sums. Another gem.