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Space Tug to Save the Hubble?
Aglassis writes "In an article at SpaceRef, the CTO of Orbital Recovery Corporation claims that his company will be able to develop a space tug that could save the Hubble Space Telescope (from becoming 'a ballisticly implanted reef in the Pacific') by either moving it into a much higher stable orbit, or by moving it to the ISS where it could be maintained and operated. Some of the reasons that he cites are that the Hubble's replacement, the James Webb Space Telescope, could be delayed or suffer some sort of failure. Since the JWST will be at the L2 point, servicing will be impossible."
Since the US doesnt have a replacement planned to be sent up until 2010, and that by not servicing the HUbbell it may die by 2007.... Bringing it towards the ISS would allow it to be refitted and keep science moving forward!
Adaptive optics can do a lot to cancel atmospherics. The real problem is that the atmosphere just plain obstructs much of the spectrum.
Trouble making decisions? Just flip for it.
I attach below the text of a letter recently sent to European astronomers, regarding the demise of Hubble support:
Dear colleague,
As you may know, NASA has decided to cancel all further servicing missions to Hubble. Servicing Mission 4, originally scheduled for next Spring/Summer, was designed to refurbish HST and enable it to continue operating in the current efficient and successful way. NASA has decided that all future Shuttle missions will be devoted to the International Space Station. Hence, no upgrade in capability or maintenance is planned for HST. A direct consequence is, of course, the end of WFC3 and COS as HST instruments. A discussion is developing, however, on the possibility of launching one or both of these instruments as part of a "fast-track 2 meter class telescope" mission.
Without the replacement of failed gyros there is a high probability that HST will have to be operated in a two-gyro mode relatively soon, with substantial restrictions on the science observations. A controlled de-orbit of the spacecraft will have to be achieved using a special robotic mission at some time in the future as yet unspecified.
There is little we Europeans can do directly to change NASA's decision which, apparently, is final. We believe strongly, however, that it should be made known how universal the feeling of disappointment is within the scientific community. As European members of the Space Telescope Users Committee (STUC), we have asked the ST-ECF to open a web page where you can send comments on the fate of HST and on the loss for the scientific community. We encourage you to share your views with us, visiting the site and sending e-mails to the address given.
The site is now available at http://www.stecf.org/SM_cancellation.html
Best regards,
Eric Emsellem and Monica Tosi
Tubal-Cain smokes the white owl.
More significantly, there is the issue of orbital inclination (the angle between the orbit and the equator). Hubble is at a comfy 28.5 degrees, which is optimal for shuttle launches from KSC given the launch site's latitude. ISS is inclined at 51.6 degrees, which is more of a 'climb' from low-latitute launch sites like KSC, because of the need to launch materials from Russia. (Low latitute launch sites get an extra 'kick' from the earth's rotation, the more equitorial the orbit.)
Transferring in altitude and orbital plane is no easy trick, (http://liftoff.msfc.nasa.gov/academy/rocket_sci/s atellites/hohmann.html) but can be done (just check the math... a lot).
Even if it's done though, NASA would have to commit to service the HST for a few more years. And, although their "official" reason for canceling the HST Service Flight is "safety," the real reason is funding. It may be cliche, but as the line goes, "No Bucks, no Buck Rogers."
I would bet there are gaggles of astronauts who would volunteer to fly a HST service flight with these risks and I'd much rather spend $500 million (most of which is already spent on the hardware and training) to support HST for another 5-7 years than on anything else, including ISS or Pluto-Kupier. Otherwise, we're left with a HST which is one failure away from becoming an orbital paperweight (if there is such a thing) and $200 worth of already-built flight hardware sitting in a warehouse somewhere.
Bush Lies On the Record.
>Since the JWST will be at the L2 point, servicing will be impossible."
You can still service it there. What that should have said is it will be impossible ***with the shuttle***.
The L2 point is beyond the moon. We currently do not have the capabilities to launch manned missions that far out.
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The James Webb Space Telescope is really not a replacement for Hubble. JWST is primarily an IR telescope, and HST is a visible light and UV telescope. Different but complimentary missions. Even if JWST goes up, the loss of HST prematurely will hurt science.
-G "We love to buy books, because we are buying the belief we have time to read them" - Warren Zevon
L2 is a point about 1.5 million kilometers away from the earth, essentially right "behind" the earth if you look from a vantage point near the sun. This means it's about four times farther away than the moon - much farther away from the earth than any human has ever flown. It would take an enormous amount of time and fuel (and thus money) to get anything out there, so it's something you don't do very often.
Which of the wavelengths that the hubble can shoot which ground based cannot will fail to be served far, far better by Webb?
The UV. Our atmosphere is opaque to the UV, and JWST, being an infrared optimised telescope, isn't going to be capable of observing the UV at all.
Its important to note that JWST is not a simple upgrade to HST. It has a very different mission and set of instruments. Its not just HST with a bigger mirror.
Ahh, Adaptive Optics. Their proponents keep forgeting about that pesky atmosphere isn't just distorting light, but absorbing it. No matter how advanced optical adaptation becomes it can't resolve the photon that doesn't arrive.
The potato it is uninformed.
Oh no, a Slashdot superstar is flaming me. I am now too afraid to post ever again (sob).
Actually, since I must now defend myself, I read this article the other day.
http://www.msnbc.msn.com/id/3982359/
And my OPINION, is that the President's new space initiative is election year rhetoric.
Having a bookmark to Google does not make you an expert on everything.
The L2 point is beyond the Earth's umbra and lies in the region of Earth's penumbra called the annular umbra. Further the planed orbit for the JWST will not exactly be at L2 but rather in a more stable configuration around L2.
Earth-Sun L2 and shadows
The problem of piling up a load of old junk around the ISS is that they'll be in very slightly different orbits. Without continual orbital adjustments there would be a very real risk of collisions.
Hubble is operated and funded by NASA, but all science planning and data analysis is done by Space Telescope Science Institute on the Johns Hopkins University campus.
The key is funding.
If you can get people to and from the surface of the Moon, getting to and from Sun-Earth L2 is arguably easier and safer. So we can service JWST with our lunar fleet.
Not true. Getting to lunar orbit is actually easier, since you don't have to come to a complete stop -- you "only" have to slow down enough to be caught in the moons gravity. You still have _a lot_ of momentum.
A service mission at the L2 point means you have to decellerate to a complete stop and then accellerate back. Doing that requires much, much more fuel than going to the moon.
Every day, Hubble archives 3 to 5 gigabytes of data and delivers between 10 and 15 gigabytes to astronomers all over the world. See science highlights. As of March 2000, Hubble has:
Art by Mindy Herman, my wife.
Most Slashdot readers will be too young for this one, but this it practically a script out of Salvage 1. Andy Griffith played the salvage engineer turned astronaut who first rescues a falling satellite, and later goes after the descent stage of a LEM.
"Can there be a Klein bottle that is an efficient and effective beer pitcher?"