I spotted a little article last week about a pallet of old batteries that had been dumped out of the International Space Station three years ago. Per plan, it took three years to deorbit and burned up over the Gulf of Mexico during reentry. Geeks can read about it on Ars Technica. (My favorite space news site, btw.)
The intriguing bit for me wasn't the discarding or the deorbiting of space trash to burn up on the way down, this is done all the time. (Hitting the Earth's atmosphere at tens of thousands of kilometers per hour does build up a fair bit of heat.) No, what I found intriguing was this number: the mass was 2.6 metric tons, 2600 kilos, 5800 pounds.
That got me thinking about what it cost to put those batteries into space to begin with. Not knowing which launch platform sent them aloft, I thought I'd dig a little deeper.
Ignoring the Details
R&D costs get mitigated over time. For example, 6 Apollo missions landed on the Moon. Including the launch pad fire of Apollo 1 and the failed Apollo 13 (failure to land otherwise an amazing success in saving a crew a quarter-million miles out in space), there were 6 other Apollo missions. For each successful landing, there was an R&D or failed flight. There were 3 more planned Apollo missions that were scrubbed. These would have shifted the math from 6-to-6 "other" flights-to-landings, to 6-to-9. It would have spread out the development costs by another third.
The Space Shuttle was proposed with this specifically in mind. Each of the five orbiters (a sixth was built but never flew) were rated to 100-launch lifecycle. Of the proposed 600 launches with those 6 birds, 135 were flown. So, the program costs were spread across 22% of the launches.
Early Days
The early days of space flight are almost incalculable. Vast research costs were a given. But the first men put into space were done atop converted missiles with so few safeties that I still can't believe there were so few fatalities. Before the Apollo 1, Soyuz 11, and two Space Shuttle disasters, there was only one fatality: the parachute on Soyuz 1 failed to open and the capsule crashed.
By the time we get into Apollo, we start getting the first hard numbers of real costs: about $5-$40,000/kg. I weigh about 170 pounds, 77 kilos. So, without my spacesuit, any food, water, or a capsule around me, I would have cost $400,000-$3M to launch into LEO (Low Earth Orbit) depending on the vehicle and how you calculate the costs. To the Moon looks to be, based on the numbers I can find, about four times more expensive per kilogram (now I cost $1.5-12M). The reason curiously, is far less about distance or gravity. Getting into orbit at all is the huge expense. The cost is the additional pounds I would have to carry aloft in equipment like landers, the fuel weight to power the landers, and... Well, a lot of factors. For our purposes, $40,000/kg is a working number.
Choking off Space Exploration
For reasons noted above (and a pretty damned ridiculous design), the Space Shuttle became the most expensive way to move mass to orbit--ever! Now, 20 years into the space program, the costs ballooned to at least $65,000/kg. Now it takes me a minimum of $5M to send me to LEO. No wonder we stopped trying to reach the Moon when that might cost $20M for a naked human.
Mars can cost up to $200,000/kg for one-way science missions. Just sayin'.
Enter SpaceX
Prior to SpaceX, the lowest cost to LEO had been about $5,000/kg. That's all the way back to 1960s Saturn V rocket...and not much since.
The first Falcon launches? Closer to $10,000/kg.
But that's when the magic began. SpaceX figured out reusability. Not only did it save an immense amount of cost in not having to build a new first stage for every launch, but it also meant that they could achieve more launches faster. Now that heavy R&D cost is spread more and more rapidly across multiple flights (98 launches in 2023 alone and the only 2 failures were tests of the new Starship).
Costs plummeted to the $1,500-$3,000/kg range. A 2-3x improvement over the Saturn V and a 20-40x improvement over the Space Shuttle. Suddenly I cost only $120-240,000 to send aloft, down from $5M.
Batteries
Back to our 2,600kg of batteries that just deorbited. If they were there since Space Shuttle days when the ISS was built, that was a cool $169M of lift cost (aside from the batteries). An easy load for a small forklift on Earth, btw. If it lofted on the Falcon, that pallet cost $4-8M to send aloft.
Next Steps
Why are space geeks like me so excited by the SpaceX Starship (which may have flown its third test yesterday if it went off on schedule)? Most projections point to $200/kg to LEO. Now I don't cost $50M or even $0.25M to send aloft. I could cost $0.0154M or $15,400. Like the Tesla that Elon Musk sent to space, I could reach space for the cost of used car. Now that is cool. (The batteries would have cost just $0.5M to send aloft.)