Vinnie lumbers into my office with a troubled look on his face. “Something’s bothering me, Sy.”

“What’s that, Vinnie?”

“This article says NASA’s just finalized a contract with SpaceX to get the International Space Station down, all burnt up and buried in the ocean. Seems a shame. I mean, all the engineering and sweat and risk it took to build it up there, the international cooperation no matter the Cold War, the science for figuring out how to live in space — they ought to leave ISS up there as a memorial or a museum, right?”

“It certainly is a shame, Vinnie, but they just can’t.”

“Why not? 400 kilometers up, it’s not in anyone’s way. It’s all in one piece, won’t contribute to that Kessel cascade problem.”

“Kessler cascade. The Kessel Run is a Star Wars thing. But if we left ISS up there it would ultimately contribute to the cascade and in a big way.”

“It’s in space, what could break it up?”

“Actually, it’s in an outer layer of Earth’s atmosphere. Pressure up there is measured in microbars but it’s still billions of atoms per cubic meter. ISS‘ gawky structure induces retrograde drag forces, even in that sparse gas. Drag pulls ISS down about 2 kilometers per month so periodically ISS Mission Control fires rocket engines to boost it back up to nominal orbit. Takes tons of fuel each time. Smaller‑scale drag tries to rip the station apart starting with its solar panels and radiators.”

“Radiators?”

“The white panels hanging off the central truss near the middle. The big brown rectangles are solar panels that power all the station’s equipment. Any time you use energy, inevitably some of it is wasted as heat which builds up unless you eject it somehow. That’s the radiators’ job — can’t dump heat by conduction or convection up there. I read an article once that said your primary target in a space battle would be your enemy’s radiators, because once they’re knocked out whatever’s inside gets cooked.”

“HAW! Basic design flaw for the Millennium Falcon and all the Federation’s Enterprise starships. Fun to know. But I see what you mean about we can’t keep it up there. I’m a pilot, I know what drag can do when it gets a chance. Drag pulls one big chunk off ISS, the rest’d crumble quick. … Wait, now something else doesn’t make sense.”

“What’s that?”

“I thought when you’re in orbit and you slow down you go higher, not lower. You and me and Cal, we talked about that back when Cal was Al. But you just said that drag slowdown pushes ISS lower.”

“You’re right, but back then we considered the case when only gravity and momentum are in play. You’re in stable orbit when you’re going at just the right speed for centrifugal force to balance the pull of gravity at that altitude. Go higher, gravity’s weaker so you don’t need as much speed to balance out.”

“That’s what I remembered.”

“Now we’re looking at a three‑force game where drag is playing on gravity’s side. With both those guys cooperating, the balance shifts away from centrifugal force. Dragged objects slow down and drop down to a lower orbit. Come to think of it, your aircraft is in the same game. When you come in for a landing you deploy your flaps to increase your drag and reduce your lift, right?”

“Right. How ’bout that, ISS acts like an aircraft!”

“Sort of. Mostly spacecraft, a little bit aircraft. Two kilometers isn’t much against four hundred, and the air pressure’s way less. Anyway, NASA’s plan is for a SpaceX ‘US Deorbit Vehicle‘ to act like a super‑drag. If we let drag run its course with no constraints, ISS would eventually come down in pieces all over the place. Deorbit Mission Control should be able to use USDV‘s steerability to aim ISS‘ decaying orbit towards a minimal footprint near Point Nemo.”

“Point Nemo?”

“The ‘oceanic pole of inaccessibility,’ as far away as you can get from any piece of land. It’s also far away from regular shipping and air traffic. Can’t say much about whale traffic though.”

~~ Rich Olcott