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Change In Experiment Will Delay Shuttle Launch
necro81 writes "A $1.5 billion gamma ray experiment, the Alpha Magnetic Spectrometer, that was to have launched aboard the space shuttle Endeavor to the International Space Station in July, has undergone a last minute design change that will change the launch date, pushing back the end of the shuttle program by at least several months. The change replaces the original liquid helium-cooled superconducting magnet with a more conventional one, which will reduce the risks involved (superconducting magnets can be problematic — just ask CERN) and will greatly extend the useful life of the spectrometer (the liquid helium coolant would have boiled away within a few years of launch). Although the conventional electromagnet is only 1/5th as strong, its increased lifespan should allow for substantially more science to be conducted, especially considering the ISS's extended mission life. As the change is still underway, the impact to the final shuttle schedule is not fully known."
IAASIE (I am a space instrumentation engineer) and I really find such a major last minute decision hard to believe, seeing how long and detailed the flight model / integration tests are...
If only it ran Ubuntu, then we'd know what's the Shuttleworth.
I wonder if this delay extends the set of contingencies (such as reboost, de-orbit, or repair) for the experimental unmanned space plane currently on orbit. The recent X37B liftoff was on a much lower inclination than the ISS's and "is designed to fly at altitudes between 110 and 500 nautical miles, or 126 to 575 statute miles" according to SpaceflightNow. This puts it within reach of Endeavor. The last time a supersecret bird went awry, they had to shoot it before it fell to keep it from raining hydrazine and beryllium on populated areas ... or so they said.
Obi-Wan: "I felt a great disturbance in the Force, as if millions of voices suddenly cried out in terror and were sudden
Um, please remind me, how did they orbit the Hubble?
Just throwing a question out there: What's holding back the use of high critical-temperature superconductors in applications like the AMS magnet? Helium cooling is a vital, yet difficult and expensive proposition for many high-profile physics projects, to say nothing of innummerable NMR and MRI magnets out there. I realize that as ceramic-type substances, cuprate superconductors aren't as easily drawn into wire as the niobium alloys commonly used, but it seems like those technical challenges are worth dealing with in order to cool with liquid nitrogen rather than liquid helium. Particularly the superfluid helium that was planned for AMS- that stuff abhors a container. Is there some other physical limitation to cuprates that I'm missing, or is it just that the multi-decade nature of the big projects have kept them from adopting newer materials?
"FDA staff reviewers expressed concern about the number of patients who were left out of the study because they died."
Come on now. You're not even trying anymore.
Space itself is cold, yes (high vacuum means there are very few particles to vibrate, so low temperature). HOWEVER, the solar radiation heats objects up rather nicely. If solar radiation didn't heat things, we'd be frozen here on earth too. To keep this instrument cold by exposing it to space would require a giant sun shield.
Submitter is a moron who does not know what he is talking about.
If you're going make that sort of statement, you could at least:
1. Offer up some evidence to back up your statement. A link would do.
2. Sign your fucking name to it.
Thank you,
The Internet
This ain't rocket surgery.
Space isn't actually cold. There's nothing there to be cold. In order to transfer heat, you need something to transfer it into, and there's just nothing there.
See this excellent discussion of cooling problems for the Star Wars planet-city Coruscant.
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AMS is not a gamma-ray detector. It is designed to measure cosmic rays. http://ams.cern.ch/AMS/ams_homepage.html
Hulk Smash
. .
AMS is one of the poster children for a capability that will be lost with the retirement of the shuttle, a capability many insist we don't need - intact equipment return.
The original plan was, when the cryogens ran out, to return AMS to Earth and rerun the pre launch calibration checks (essentially using a particle accelerator to shoot particles through the AMS) - not only allowing us to learn about the effects of the orbital environment, but also being able to apply the knowledge of those effects to the analysis of the science data collected on orbit.
There was no reason to use a manned launcher to orbit the Hubble.
For the cost of the repair mission and all the other worthless manned flights they could have put up 10 Hubbles.
Tsunami -- You can't bring a good wave down!
What kind of experiment are we talking about (/should i have read TFA for) here?
the major objectives of the experiment is to look for alpha antiparticles Window
Let's not swap one absurdity for another. Space is extremely cold, at about 3K. Poor heat transfer is an orthogonal issue, which prevents you using space as a heat sink. If a device is generating its own heat or picking it up from (solar) radiation, it will heat up. If it's inert and in the shade, it will get cold and stay cold.
No kidding!!! What do you say at this point?
Ten Hubbles that wouldn't have worked properly because of the optical defect. Having a temporary repair platform shouldn't be necessary, but it sure was handy in this instance.
No kidding!!! What do you say at this point?
If an object radiates away all its energy because it's in space, it doesn't get cold because space is cold. It gets cold because there's nothing there to radiate energy back into the object.
You can say that the stuff in space that isn't just empty space has a temperature, but it's so spread out that radiation becomes the dominant mode of heat transfer, and it has such little mass and is so cool that its black body radiation is meaningless. It is effectively not there for this interaction.
When you're afraid to download music illegally in your own home, then the terrorists have won!
No. Your model is of an object in an infinite, unbounded void, a void which would indeed have no temperature to speak of. However that is not the universe. Any subset of the universe exchanges heat with the remainder, and would do so even if radiation was the only mechanism of heat transfer. Therefore thermodynamics allows that we can - and must - talk about the temperature of space in a sensible way.
If you take an object and you place it in the universe in a cavity which (for the sake of discussion) is large enough that the universe appears reasonably homogeneous, it will cool until net heat transfer stops at a finite temperature of around 3.5K. By the thermodynamic definition, the object and the universe are now at the same temperature. Ergo, the universe has a temperature of about 3.5K. Ergo, space is cold.
This isn't to dispute that an object which needs to lose heat at any significant space cannot do so to space. That's an entirely seperate issue.
No kidding!!! What do you say at this point?
Any significant rate
No kidding!!! What do you say at this point?
Nobody said they had to launch them all at the same time. Could have been 1 that didn't work and 9 that did.
Even more sobering: if the above cost analysis is correct, it could have been 9 that didn't work and 1 that did, and we'd be no worse off.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
The above "cost analysis" was hyperbole pulled out of the poster's ass. Your delicious understatement of the benefits of having 9 simultaneously operational Hubble telescopes only underlines the hyperbole. No worse off? Try fantastically well off. Astronomers would be giddy for months for the chance to gain access to such an armada.
I'm not especially pleased by the ridiculous expense of the Shuttle, or the welfare for engineers that it represents, but on the other hand I believe that any organization not practicing an activity rapidly becomes incapable of that activity and has to relearn it from scratch if someone wants to resume that activity. Going around in circles for the last 20 years at least kept our hand in. There is still a crowd of people who know how to do manned space flight, and prove it on a semiannual basis. If we hadn't been doing it, you could say definitively that we wouldn't really know how.
There's some argument to be made that the way NASA goes about it, they don't really know how either, but that's another problem...
They had really advanced technology long time ago in that galaxy far, far away. They could be dumping their waste energy into hyperspace. They could even be using fusion as a heat sink. How much energy does it take to make an iron atom, or an oxygen molecule?
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Someone really needs to fix the summary because it is NOT a gamma ray experiment at all. It is a cosmic ray experiment that detects baryonic matter (protons and small nuclei).
It is a galaxy populated by sword fighting space wizards. Is a plausible explanation strictly necessary?