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A Way to Save Hubble?
An anonymous reader writes "The maintenance flight to give the Hubble Space Telescope a few more years has been cancelled, even though everyone agrees that HST does good work. But this article offers a way to save the space telescope, and to give those who think the space program should be privatized a way to prove they can do it."
At least we should boost Hubble to higher orbit, so when NASA gets additional funding, it can try again to bring it down. Putting it in a museum somewhere would really be a inspiration to many children to go into science.
we have roughly 3 years before the HST becomes unusable.
also, the construction of the ISS, IIRC, is not "complete" yet.
wouldnt it be obvious to build another, better Hubble-like telescope and attach it to the ISS instead of some other planned component, or if the ISS vibrates too much, maybe have it tethered?
the ISS has permanent people on board to fix, or at least to do in situ assessments, should any problem arise.
plus the Progress can provide supplies if parts are needed.
could a ISS-based telescope be built in 3 years?
Let the markets determine where the research should go, but provide encouragement to keep the products of the research in the public domain (or at least cheaply licensed). I'm not expecting Monsanto or ADM to grab at this opportunity wholeheartedly, but smaller companies or divisions of larger ones might grab at the tax break for research that's important but not at the core of their business model.
Get off my lawn.
NASA says no shuttle flights to anywhere but the ISS for safety reasons. What about using a shuttle flight to take one of the existing space vehicles to serve as a space taxi to carry astronauts and material to and from the Hubble. Take a modified Gemini capsule, (it was made for testing orbital rendevous and docking procedures) give it a modified support module to carry the fuel and spare parts for doing the orbital adjustments and let them 'taxi' over to the Hubble when the orbital mechanics are favorible, accomplish the support mission and catch up to the ISS on the way back. While it is rocket science; it is with small modifications that can be made to previously proven vehicles; not a multi billion dollar idea. If they can't make it back they can always reenter the old fashioned way. If they do make it back then we have a relatively inexpensive space taxi for future use. Hell, you could fit 2 Gemini capsules and service modules in the shuttle cargo bay and have room left over!
"Can there be a Klein bottle that is an efficient and effective beer pitcher?"
What exactly would Hubble need to keep working? Boosting to a higher orbit, because its current orbit is decaying? And Hubble's gyroscopes are wearing out, and will need replacing.
So, how expensive would it be to build a robot that gently grabbed ahold of Hubble, gently boosted it to a higher orbit?
Would it be possible for a robot like this to use its own gyroscopes to keep Hubble stable?
Yes, I know there are also new lense modules, and similar, but they would require an astronaut to install them. Well, maybe they can wait until the safer replacement for Hubble is ready.
Could the robot have enough fuel to move Hubble to orbit next to the ISS?
There is supposed to be a replacement for Hubble, that may be ready in ten years or so. But it might not be ready. And it might not work. Hubble works. Maybe they should keep Hubble until they know the replacement works...
Hmm, do the authors have a bias for space telescopes, I wonder?
All of their arguments are correct - for now. The problem is in one word scale. Physically, extremely large telescopes aren't really feasible to send into space - to LEO or to the Moon, regardless.
However, oddly enough, the moon - being basically made out of the same stuff Earth is - has all the raw materials to make mirrors.
So the idea isn't to send a telescope from the Earth to the Moon.
The idea is to build it on the Moon in the first place.
This would require a lot of R&D, and a lot of work - but that's just R&D, which can be much cheaper than the launch costs of a gigantic telescope (a many-meter telescope).
The authors also then go to say "why would we want to keep a state of the art instrument around for a long time?" implying, of course, that state of the art changes so rapidly that keeping something around for a long time is meaningless.
They somewhat fail to see one thing: a gigantic mirror will always be state of the art. If the instruments need to be changed periodically (say once every 10 years) then the marginal cost of replacing instruments on a telescope on the Moon (assuming that the capability of getting to the Moon exists) is going to be infinitely less than launching a new state of the art space telescope.
Basically, the authors are assuming that
While this is certainly true now (and validates the reason that their one example - LUTE - wasn't chosen, as it would have been an unmanned observatory) - it is definitely not arbitrarily true for the future. Assuming that lunar human infrastructure exists, and lunar manufacturing capability could be constructed, the cost of building a telescope on the Moon is tremendously cheap.
The argument against the Hubble maintenance mission is that it would not have the ISS as a safe house if the shuttle makes it to orbit but is not safe to come back down in. Therefore any mission to other than the ISS requires making up the repair kit that the safety board recommended.
Well hogwash! The safety board didn't say build the repair kit only if you go elsewhere, they said build it period. It would still be a good thing to have, even if the crew can hideout in the space station. Second, if no shuttle goes to Hubble, they have to build a special remote operated tug to match orbits with Hubble to bring it down under control, rather than let it wobble around and possible land big chunks on people. But a repair mission could install a much simpler de-orbit rocket as part of its mission, and I bet the costs would be a lot less, compared to designing a one shot remote operated booster.
Infuriate left and right
I've now fallen out of the chair, and yes I've read all your sentences. Your argument is basically: assuming no launch costs, no personnel costs, a cost-free fully-outfitted manufacturing facility (that needs to make mirror substrates out of the lunar soil! Go visit the Corning glass facility and get an idea what kind of power and cooling requirements you need), a cost-free fully-outfitted optical facility (including dedicated clean rooms), and pretty much ignore the remaining costs, the lunar optical telescope is essentially free.
The expensive part of building a space telescope is the optics. Glass is heavy (even when they lightweight it), and if you go to segmented and/or sparse systems, you get the weight back in the metrology and control systems (which you refer to as the adaptive optics).
I'm not sure how far in the not-to-distant future you are dreaming, but until we have a Flash Gordon world with not little bases, but cities on the Moon, you're not going to have the facilities or resources to do what you are talking about. Especially for something like building telescopes. They'll do radio arrays, but don't expect to see telescopes looking at anything shorter than tens of centimeters unless it is either brought up as a monolith, or it is doing Michelson beam combination.
Your comment about steel mills is way off too. These mills live and die on the margins. These plants do what they can to squeeze an extra percentage of efficiency where they can get it because that means millions of dollars a day for the amount of steel they put out. They are large and power hungry because of thermodynamics. There are basic metallurgical requirements for turning your raw materials into steel, and believe me, you'll never have to work another day in your life if you can come up with a steel-making process that is even 25% more efficient than it is now. That's why that story last month about that researcher who found he could use microwaves to make steel is such a big deal; if that process works, and it can be industrialized, that man will be very very wealthy.