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NASA Announces De-Orbit Mission For Hubble
maglor_83 writes "NASA has announced the end for Hubble. It plans on performing a "robotic de-orbit mission", and apparently its not due to the monetary costs associated with fixing it, but rather the risks involved. NASA's new goals are now manned missions to the moon, as a platform for Mars."
You can learn why a fourth servicing mission is necessary by reading my article. I say: "several components of Hubble, most probably its batteries, are expected to stop operating in the next 2-4 years" and "HST was designed to be maintained with servicing missions operated from space shuttles every few years" (i.e. it is impossible to keep Hubble there without launching servicing missions, we need to fix its orbit and replace components every few years). In addition, the gyroscopes will also stop working, but I think the most important problem will be its batteries (Hubble can work with just 2 or 3 gyroscopes, but not with dead batteries).
The gyroscopes are wearing out. They've done so before and been replaced, but they're going again and the batteries are fading. Without at least 3 gyroscopes Hubble can't be pointed accurately, and with less it starts having trouble maintaining attitude control and could potentially start to tumble and deorbit.
It doesn't need repairing today, but it will in a couple of years. The batteries and gyroscopes have limited lifetimes and must be replaced every so often. These cyclic repair missions, which have been performed in the past, were cancelled after the Columbia accident
While they could restart the repair cycle, NASA no longer feels that repair flights are safe, because, unlike when the Shuttle visits ISS, there are no good rescue options given Hubble's orbit.
The moon would be a good place for a prototype space elevator.
No, it wouldn't be. Basic space elevator is essentially just a tower to geostationary orbit. Earth, rotating just over once every day (!), that's an orbit radius of 42,000 km. The Moon's equivalent orbit with it rotating once a month (albeit with lower gravity) is about 90 million km, assuming this back-of-the-envelope calculation is right.
The best place for a prototype space elevator would be a small asteroid with a fairly high rotation rate - you could probably get away with a few tens of kilometres if chosen carefully...
Tedious Bloggy Stuff - hooray?
JWST is not a full replacement for Hubble - it is primarily an IR scope, with some visible capability - it lacks certain wavelengths Hubble covers, like UV, which is one of the primary benefits of launching a space scope in the first place. The band in question, covered by Hubble but not JWST, is the 110nm-600nm band. JWST has significantly more infrared extension than Hubble, but infrared is one of the more usable windows from Earth, especially as adaptive optics techniques improve.
Basically, JWST is not a full Hubble replacement. A good thing to launch? Yes. But we'll definitely lose some capabilities in the bargain.
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Mod me down, you fucking twits. Go ahead. I dare you.
(I read with sigs off.)
It might be in itself, but you're forgetting something important: Lagrange points. The link below explains how a lunar space elevator can be done.
http://www.universetoday.com/am/publish/lunar_spa
Not only would it be possible, the entire cable could weigh just 6,800 kg according to the article's calculations.
(It's been a slashdot story, but the usual searches wouldn't find it)
Hate to break it to you, but Florida's economy is not driven by NASA. Cape Canaveral and its suburbs house only a tiny fraction of the population there. Saying that NASA is their "key reason for existence" is simply retarded.
After all, I am strangely colored.
Hubble was scheduled to be brought down and put in the smithsonian. In fact, the display mount is already in the air & space museum (or was a couple years ago when I visited). The problem is that the Colombia was the only shuttle decked out to down mass the Hubble. All the other orbiters are setup with an airlock and docking port for the ISS. Hubble won't fit in the cargo hold of those orbiters now.
"You never know when some crazed rodent with cold feet might be running loose in your pants."
-Calvin
Unforch, there is no "Dark side of the moon" in terms of a permanent dark side. Its day, and its night, are each nominally 2 weeks long. Yes, it maintains the same face toward the earth, but thats not the same else we wouldn't have the phases of the moon as the 'dark side' rotates around the moon as it rotates around the earth.
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Cheers, Gene
I think you are refering to one of these two articles
Lunar Space Elevator Instead?
Space Elevator Prototype Climbs MIT Building
-William
God is everything science has yet to explain.