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Recycled Satellite Yields Scientific Treasure
Rob (not Malda) sent us this story about how UC Berkeley astronomer Derek Buzasi found that a satellite with a malfunctioning main telescope had a perfectly functional "spotting" scope that could still be used to gather valuable data. Now, because of Buzasi's inspiration, the Wide Field Infrared Explorer (WIRE) satellite NASA had written off as a $73 million piece of space trash is a useful astronomical tool that makes approximately 750,000 observations per day.
The ordinal of one.
Xah
xah@best.com
Xah
""Perl my ass" (there are more than one way to express love, too!)"
The problem is that all the cooler evaporated away because of a bug during launch. To fix it you would have to refill it. My guess is that
a) The satellite is in an orbit unreachable for the shuttle (it can go up to only about 400 kilometers after all, far lower than e.g. earth resource satellites like ERS-1 and 2, and weather satellites like NOAA).
b) It's maybe not possible to refill the cooler.
My guess would be for a) but I don't remember the orbit -- I know that it was mentioned in the press release at the time.
TA
Why not collect the space junk with a net like industrial fishing. Not everything out there is moving at 16,000mph. A large net with a streamer dropped into the atmosphere would drag itself and whatever it caught into the atmosphere. The shuttle could drop one or two every mission and eventually clean the low earth orbit. With no moving parts they would be cheap.
Hubble was much more expensive so repair was more cost effective than replacement. It may not be the case for this one.
I work on projects for NASA, currently helping to build equipment to fix the broken IR camera on Hubble (NICMOS).
Some posters have correctly answered some of the questions about WIRE repairs, but here it is in a nutshell:
Hubble was built to last 25 years, and replacing the instruments was always planned as new technology was developed. These aren't 'repairs', they are 'upgrades' (ignoring the mirror problem here).
IR cameras need to be cooled to 35-60 K so faint IR radiation can be detected. Parts of the optical path must also be cooled to prevent background heat from the instrument from swamping the detectors. Since WIRE was planned to be launched on a rocket to a polar orbit, no provisions were made for in-orbit repair since the shuttle can't reach that orbit.
Someone else correctly stated that the costs of a repair mission would dwarf the cost of WIRE, so it would be cheaper to build on new one (except Congress is attempting to swipe $1.3 billion from NASA'a 2000 budget, so don't count on it).
Another point, besides the financial issue: If I recall correctly, WIRE was launched from Vandenberg in a polar orbit; the shuttle is not able to attain a polar orbit from Kennedy. A long time ago, there were plans to do polar shuttle launches from Vandenberg, but I haven't heard anything about that in a decade or more.
UNIX allows you to do this: man nice, man renice. Red
Leave it up to a hungry scientist to find the silk purse in the sows ear. :) It's still a bummer that the satalite can not fulfill its orginal goal (and another $70,000,000.00+ will be spent replacing it most likely) but at least it is not a total loss.
Now if only I could work out the finite improbablity of that danged Infinite Improbability Generator NASA's been trying to build....
Boobies never hurt anyone. - Sherry Glaser.
On that same thought, why not build "Spaceballs" MegaMaid and clean up that way?
.. .
...
"I call it, the SuckCut"
"Cha! It really sucks!"
Large print giveth, and the small print taketh away
You mean, for once, a government agency will actually save us some money by recycling "waste"? wow.
Someone call Perot!
Try looking at stars in the daytime ;-)
Good judgement comes from experience, and experience comes from bad judgement.
- W. Wriston, former Citibank CEO
I'd guess it's more a bandwidth problem than a computational one. In other words, simple calculations on a huge pile of data, rather than intensive number-crunching on a small packet.
Still, it would be interesting to offer, and I'd gladly drop RC5-64 for this project.
distributed.net would love to tackle some more scientific projects, unfortunatly, our current network isn't readily adaptable to most of these endeavors. We are having a tough enough time setting things up for OGR, let alone a project that would require moving large amounts of data around. }:8(
BUT, we are always looking for future projects! }:8) So, if you are involved with a scientific endeavor that you think a network of 70,000+ machines could do useful work on, please feel free to contact me directly at decibel@distributed.net. (Please, only contact me if you have direct contact with a project.)
Mooo!
dB!
Hey! We want to help! The man said that he's drinking from a firehose of data.
We have a little idea about how we can help you analyze the information. See if you can get distributed.net to take your project. Some of us wanted to be scientists when we grew up, but we became computer programmers instead. That doesn't mean that we ever gave up the dream. I'd love to contribute cycles to this project.
If tits were wings it'd be flying around.
How much does one cost? Roughly.
If tits were wings it'd be flying around.
It is my understanding that a faulty computer chip had a bug in it that caused a cover over the dewer to be released too early during launch. This unfortunately, heated the dewer and the hydrogen cryogen then vented at a relatively extreme rate. Since the cryogen is completely vented, the detector cannot be cooled. The detector must be cooled in order to measure the low amounts of radiation that it is intended to measure.
I don't know if their web page is official or not, but it has many pictures. Actually, I could have saved the typing as the first entry (1999 March 29) describes the failure. So read it there.
~afniv
"Man könnte froh sein, wenn die Luft so rein wäre wie das Bier"
~afniv
"Man könnte froh sein, wenn die Luft so rein wäre wie das Bier"
Richard von Weizs
This topic has really gotten me thinking about how distributed computing can apply to astronomical data analysis. Unfortunately, as someone mentioned above, actual astronomical observations can require some massaging by hand, so distributed analysis is less than straight-forward. This is the case with WIRE, for instance.
However, numerical simulations could be pretty easy to distribute. My current simulations of starburst galaxies take about 10 hours to crunch on a quad processor (296Mhz x 4) ultra w/ half a gig of ram. I'd like to run, say, a million of these per galaxy I'm studying, but this is entirely unfeasable with the computing resources I have available to me.
I've already started talking with my advisor about distributed computing for our simulations. The seti folks really have the right idea here. I'm surprised nobody else in the astronomical community has taken advantage of this yet....
-zeno
WIRE was only intended to be used for 4 months because of the cooling issues that another poster has already explained.
They couldn't have even hoped to have a repair mission up there within the 4 months that they were originally working under.
Again as another poster pointed out the cost of the repair would have been much more than what it cost to build.
Does anyone know more about the "little known bug in a computer chip" ?
Sheesh, evil *and* a jerk. -- Jade
It's great that there is some use for this otherwise floating piece of junk. However, the article, to my recolection, doesn't mention why the main scope can't be repaired. They hacked the hubble back together, why not do something similar for WIRE?
"Darned clever these Earthlings..."
I think it's not the space junk so much as the rogue micrometeoroids that you have to watch for. (Not that that makes the situation much better.)
--
Now if only somebody could find a "perfectly functional" use for M$ products.
If this guy can dig up some good pieces from a otherwise junk sattelite, I wonder what other stuff is up there that we could use? It wouldn't have to be the cream of the crop stuff, just the things that NASA has written off as end of life. I bet we could get quite a trove of data off of some of the still working stuff.
The reason WIRE cant be repaired is because it lost all its frozen hydrogen into space, and without that the infrared camera will just be taking a picture of a warm lens instead of the heat eminating from 'out there'. To repair it it would require going up there, cracking it open and putting new frozen hydrogen inside which would cost more than the satellite itself cost to make. Someone was meantioning opening up the project, couldnt work here but it got me thinking about something else. Why hasnt anyone built some sort of standardized interface for this? You could have something akin to the dead idea of push technology but it would allow you to donate certain amounts of processing power to projects you find worthwhile. In screensaver mode then, you could donate 25% of your processor's time to SETI@home, and 75% of your processor's time to crunching the math for rendering the latest disney film, cryptography, number crunching star-burst galaxy data, etc. Sounds like a cool idea if you ask me.
http://www.livejournal.com/users/cixel
There ought to be some regulations that specify that all sattelites going into orbit have a small seperate booster for reentry and burn up. If the sattelite fails or has gone past its usable life this could be activated removing it from our debris field. We also ought to develop a "clamp on" solution that the shuttle could take up and send a couple old pieces of junk back to earth with. Just light fuse and get away. I'm sure for larger stuff this would be unfeasable but all the small dead sattelites and junk up there... there has to be a solution.
Man this Chineese food is good today.
However Yesterday's Microsoft FUD gave me indigestion.
www.mp3.com/Undocumented
It's nice to see that the $73 mil that was spent on the satellite isn't totally going to waste. It constantly blows my mind when I hear about all the junk that is floating around up in the near orbit. Heck, it's a wonder they can even put anything else up there with all the satellites and debris that's flying around...
"You did WHAT to WHO for BEER MONEY?!? Jeez, man - you don't even like beer..."
... reducing astronomical data often can't be sped up by throwing more processors at the job. The Seti system is a case where the data reduction is straight forward, so it can be distributed easily. However, an astronomer often has to make adjustments to the data analysis process by hand, for each target or each set of targets, depending on the observing conditions and what you'd like to know about the target.
:) I'm sure scientists will start to ask for your help more and more over the next few years... and maybe, depending on the methods involved, this will be one of next distributed projects.
Perhaps the sort of data their getting from all their targets is similar, and can be reduced using the same method. Perhaps, though, their looking for different things from different targets, so a general enough distributed method that is convenient for the astronomer is difficult to design.
I'm glad people would like to participate in distributed data reduction and scientific computing. I think it's a heck of a lot more useful to society that cracking one of an infinite set of code keys.
Hope this sheds some light on things!
John
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This is an obvious plug. We're a small company and don't have our named mentioned all that often. The star tracker (as it is really called) was built by Ball Aerospace. It is the Ball CT-601 model tracker with a 7.5in shell and 92mm lens, so I'm told.
Our trackers are used all over the place, so perhaps other spacecraft can be used similarly.
Needless to say, our star tracker folks are excited.
~afniv
"Man könnte froh sein, wenn die Luft so rein wäre wie das Bier"
~afniv
"Man könnte froh sein, wenn die Luft so rein wäre wie das Bier"
Richard von Weizs
It's undoubtably super news that there is an aspect of the satellite that may prove useful. Having any telescope in space, even one as small as this spotting scope is astonishly great for calibrating ground-based telescope observations which need to be made through miles of crud in our atmosphere.
But while this is a small improvement on what would have been a total loss, it is certainly not going to be free. For every active satellite (or even any active ground-based telescope to a lesser extent), there is a substantial expenditure in maintainance and data processing. For a satellite a large part of the price comes from ground operations, including issuing commands and maintaining a downlink station to receive the data as it comes in.
More information for the confused: Why is a tiny telescope (2 inch diameter) in space such a big deal? After all, anyone could pay about $200 and buy a telescope from a department store with equivalent light collection power. The key is that any telescope in orbit is above terrestrial weather. Measuring stellar brightness and color (which in turn yield info about a star's age, mass, distance, etc) is difficult from the ground because the atmosphere is not transparent. Weather makes the transparency change on short timescales, so a star's brightness appears to change rapidly. This is especially difficult for an astronomer who wants to study stars which have intrinsically variable brightness.
In short, a little satellite-borne telescope is a stable instrument for consistent work, like all those 386's running Linux and serving web pages out there.