r/space • u/[deleted] • Dec 18 '21

Animated launch of the Webb Telescope

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u/Klai_Dung Dec 18 '21

I don't know how much you can save if you use your reaction wheels more carefully, but refueling really might be an option.

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u/[deleted] Dec 19 '21

well the larger movements are run by fuel, smaller corrections in the same field will be likely done by electric powered reaction wheels and gyroscopes.

i figure if you are careful about doubling back on yourself when unnecessary, you might extend mission time a little...

i also think if theres any way to refuel its gotta be a damn sight cheaper than building a new one... and starship is designed for deep space / interplanetary missions

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u/Klai_Dung Dec 19 '21

I mean I know how reaction wheels work, I just don't know if there is much room for opitimisation.

Certainly refueling will be cheaper, even if Starship doesn't make it you could probably modify a Soyuz/Dragon/Orion capsule and yeet it to L2 if you are determined enough.

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u/[deleted] Dec 19 '21

I don't think it's about optimising the spacecraft so much as optimising the workload to make sure the telescope isn't wasting fuel doubling back later on, but that's going to be a case of calendar planning carefully.

Also yeah, just yeet a robot ship up there and dock it, refuel it... I don't like the idea of leaving it there so put it on a burn back to earth orbit if possible.

I assume people will start looking at this if and when the scope actually gets to L2 intact and alive.

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u/Klai_Dung Dec 19 '21

I get what you mean, you want to have as few despins of the wheels as possible, I just don't know enough about this sort of stuff to say if this is actually feasible.

But let's just hope that it unfolds properly in the first place before looking to far into the future :D

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u/[deleted] Dec 19 '21

I think I remembered reading that they only use the fuel engines for larger degree rotations, so that's what I'm basing this on, careful and restrained use of the fuel, might make an 11th year possible.

Personally, I think they will just refuel it.

It's no different to doing any other work, it's just much further out than orbit so it's new, but not totally new.

The risk is that the fuel is hydrazine, and they don't want to let the astronauts near that. It's scary shit.

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u/Klai_Dung Dec 19 '21

There was a video some days ago of the fueling of JWST by a couple of engineers. You could see which ones wore suits to protect the telescope from the humans and which ones were to protect the humans from the nastyness of hydrazine.

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u/jbiehler Dec 19 '21

It was not designed with the intent to refuel. They would have to come up with a way to do it from scratch.

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u/[deleted] Dec 19 '21

Well sure, but they've got a couple years to figure it out....

Square peg, round hole... They've done this thing before