Struck by debris, struck by meteor, attacked by [???], or it blowed up on its own.
Not too many possibilities and I think the first three would have very different debris signatures from the last. Although we recently had a mini-discussion about how a satellite breakup evolves into a debris field and the answer was surprising to some of us laymen.
I can’t find the cite, but I read speculation that this was the cause (specifically, catastrophic propulsion system failure), but I don’t know the spacecraft or the mission well enough to know if it even had an active propulsion system to fail that way.
According to this it did:
That’s probably where I read it.
If it had been any kind of collision, I think that would have been well-understood and at least leaked out to the news.
This was the second of the series to die early, but the first didn’t have a total unscheduled disassembly:
The failure was later attributed to two possible causes. The first was a micrometeorite impact. The second possible cause was said to be a combination of a short circuit caused by solar activity and harness issue within the spacecraft.
Geosync comm satellites have to have active propulsion for station keeping. The thing needs periodic nudging to stay in position or it becomes useless or dangerous. Typically you reaction wheels for pointing, but even those can eventually saturate and then you need an attitude thruster burn to offset the desaturation process.
As well, for many years now everything in geosync is supposed to have a end-of-life parking propulsion system to get it away from the geosync altitude so its very valuable longitude slot can be reused by whatever is going up there next.
Now whether these are ion engines, pressurized inert gas in a tank, or traditional combustible fuel+oxidizer is going to vary by design. But anything that is under pressure can burst, and anything that is flammable+oxidizer can ignite.
Yep. In LEO you can torque against Earth’s magnetic field, but that doesn’t work farther up.
You could probably do station-keeping with solar sails, but no one’s done that yet.
I’m sure it would be possible with sails, but it would be complicated and very sensitive to timing. Deploying sails would also add mechanical complexity and failure points, though it might be mass-neutral or even negative. (Don’t get me wrong, I like the idea, but I think it would be a pain in the ass to actually do. Sure would help with shifting EOL stuff to a recycling orbit later on, though.)
What sort of station keeping does a geo satellite need? To maintain position because the orbit gets perturbed, or is it losing altitude because Earth is trying to suck it back home, or something else? Thanks.
Correcting for decay and disturbances, as you note, and also for cumulative rotational forces applied during aiming adjustments. (LSLGuy mentioned this element upthread.)
Without correction, geo satellites will drift to one of two longitudes (75 and 255).
Or at least dumping accumulated spin.
I ordered a Crew Dragon from TEMU and this is what I got…
Looks like they’re copying New Shepard but with much smaller windows.
All the space firms scrambling to copy Falcon 9 and Crew Dragon are investing in obsolescence, if in 3-4 years Starship is fully operational.
Boeing may put its iconic space business up for sale and had talks with Jeff Bezos’s Blue Origin, report says
That could include the company’s Starliner space taxi program and operations related to the International Space Station, but would not include NASA’s massive Space Launch System rocket, the report said.
The paywalled Wall Street Journal article is at:
https://www.wsj.com/science/space-astronomy/boeing-explores-sale-of-space-business-fa7fa3a9
So they want to sell Starliner instead of close it down.
Huge if true. Huger if it goes through.
No idea who would buy them, though. ULA is trying to sell themselves as well. Even at a bargain price… what do they really have to offer?
They have some contracts with NASA, but even those don’t seem to be worth much. The window of opportunity for crew flights to the ISS is rapidly closing. Their SLS contracts depend on SLS itself flying, but it’s not clear how many of those there will be.
About the only Boeing space program I know of that seems well-run is the X-37 program for the Space Force. It’s flying, has no obvious reliability issues, and the Space Force seems to like it. I’m not sure Boeing is actively making money from it, though. Development is over and the main costs are to the launch providers (like SpaceX). Maybe they make a few refurbishment bucks.
The article above mentions Blue Origin, but they’re already undergoing a restructuring to de-old-space-ify themselves and maybe fly an orbital rocket at some point. I can’t see why taking on all of Boeing’s baggage makes sense.
And… bringing in Boeing’s space division probably means bringing in their union as well. I’m guessing they don’t want to do that. Could infect the rest of the company.
I’d sooner expect it to be sold to some asset strippers like KKR of Ye Olden Dayes.
Maybe, but this isn’t like Sears or whatever where they actually have a ton of tangible assets (buildings, property). I doubt they can be converted into a patent troll, either.
I suppose they could just sell the trademark rights and we’ll see a bunch of shitty consumer electronics branded with Boeing Aerospace logos.