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An experiment (probably futile) in replying to an AC:

Atheist lies

The parent article was just stating historical fact, a matter of record, really. And besides, "Atheist" is no longer pejorative, so this isn't even a good flame.

I, for one am delighted that the British are reminding themselves of their scientific heritage for this, their most ambitious space mission yet. It sets up high expectations, but that's what you need to carry something like this forward.

BTW, there are still those who claim that Viking discovered evidence of life, but this is a minority viewpoint.

They did, slashdot listened to the wrong source ...http://spacedaily.com/news/iridium-00g.html

http://spacedaily.com/news/iridium-00g.html

I am wondering if, like they suspect with Pluto, this planetismal might be able to hold a thin atmosphere. I haven't run any of the gas-law computations or looked up the kinetic energy tables to find out when (thermally and gravitationally speaking) a planet, with a certain gas mixture, would loose its atmosphere.

I'd love to see if; the Pluto Express Mission and its ilk would go through, what kind of liquid mixes one can find on distance snowballs like this. If they can't get to Pluto on time though, before it gets too far from the sun (or if they send a probe to look at one of these many *new planets* out further) they could consider using large lenses or some form of retransmitted light to cook the little rocks back up to temperature (sort of a planetary bake-off with the dial stuck to low).

This might just be me, but haven't they already established that there was indeed water on Mars in the past, leading to certain patterns of erosion and valleys and such. Stories like this and this and this (all from about a year ago) make me less impressed by this "announcement."

I think Nasa is just trying to do ANYTHING to get rid of their bad rap from the "faster, cheaper, more crashes" approach that led to the Mars debacles.

Well, this didn't go very far into the neutron star. This explosion was apparently only a layer of carbon on the surface which ignited. As the article mentions, there was a "normal" 10-second explosion at the beginning -- apparently this was a helium fusion blast, which apparently was the last straw and ignited the carbon fusion. This link describes a similar event, although the new one was 3 hours and thus much longer-lasting. Well, sometimes the dead wood piles up longer before something ignites it...

Personally I don't see any world government putting another person on the moon again

China might. OK, they're starting with bought-in Russian tech, but they might go for it for the glory of China. And like the Russians, they might get too upset every time an astronaut dies. (What DOES China call their spacemen?)
India is also shooting for the moon, first with unmanned probes as you can read here, but who knows what else.
Actually, I hope China and India both make it, and establish bases there.
More people might then go to the moon and ask "What do you fancy tonight? Chinese or a curry?"


Hacker: A criminal who breaks into computer systems

Anyway, the entire problem is ciomplicated by the fact the Sun's magnetic field is carried by the Solar wind, and there is believed to be an interstellar wind which interacts with the Solar wind. Because of these interactions and the shocks they cause, the heliosphere does not have a regular shape or size (its not really a sphere and its dimensions change over time depending on the conditions).

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"In 1997 our newest solar cell converted 21.6 percent of the sun's rays into power. In 1999 our solar cells will convert 26.8 percent, and by 2002 we hope to further improve the design to convert 30 to 40 percent of the sun's rays into spacecraft power. When you compare this to the 12.3 percent conversion efficiency of a silicon solar cell, you can see we've made tremendous improvements in order to help our customers maximize their on-orbit performance and increase revenue."

Gyro vibration. You have to continually run the gyros to keep them pointed in particular directions, and these will cause vibrations. Thursters will shake the whole thing too. If your glass it too thin you'll start it vibrating like a drum head.

Also keep in mind that structures behave in completely different ways in zero-G. You might have characterized all your structures on the lab and have damped out most of the disturbances, but you will find that there are whole different modes of vibration in space. Something that wasn't a problem on the ground is now a problem in space.

Telescopes are not hard to build because they deform under their own weight; in fact, their deformation is easy to predict thanks to Mr. Newton. Large optical quality mirrors are ground to allow for their sag on the earth.

Remember, the Hubble mirror (and other mirrors in space) is as thick as it is because it has to be that thick. Believe me, the cost per pound to put somthing in orbit is so high, they made that mirror as thin as they could. You can't just artibrarily grind off most of the mass unless you can elsewhere compensate for all the problems you introduce. Maybe they have an idea on how to correct for all the aberrations that they'll have in the mirror (such as adding an active secondary, but here you start adding more and more R&D money), but they didn't mention that in the article. Or maybe the telescope isn't supposed to be optical quality and they want to use it in front of spectrographs.

There are many efforts all over the globe to come up with ultra-lightweight mirrors for space (see for instance some work at the U. of Kentucky). If you have a good idea on how to do it, you can make some nice bucks for yourself. :)

Here's a list of all space news sites talking about this story. Compare and contrast the coverage.

And, of course, my own at Universe Today

They're actually using heated "zirconia" -> "A wafer-thin, solid-oxide ceramic disk made of zirconia, about the size of a small cookie, is sandwiched between two platinum electrodes and heated to 1,380 degrees Fahrenheit (750 degrees Centigrade). When carbon dioxide is fed to this unit, the zirconia cell "cracks" the carbon dioxide into carbon monoxide and oxygen. Only the oxygen can penetrate through to the other side of the disk; the carbon dioxide and carbon monoxide gases are stopped in their tracks." from SpaceDaily

There were actually 12 copies made, but only one was intended for space flight. And part-ownership of one of them may be for sale on ebay soon, sort of. This article at SpaceDaily.com gives details, and has a picture of the one for sale, which is currently used as a Theme Park attaction?!?!

Link to a current article at SpaceDaily.com

http://www.spacedaily.com/news/laser-00 e.html

I believe there are more links at the end of the article.

Who said anything about the Army? There are four other branches of the "Armed Services," smart guy. Certainly you learned that one in basic. Anyways, you're still wrong, but I'd just like to point that out.

Here they use them in Bosnia.
Here they are used by the ARMY Corps of Engineers.
Here's the CEO of Iridium saying "We have crystal clear communications. With the freedom to use the Iridium phones in helicopters and Army trucks, and area of total devastation and no electricity.
Here is a story about the DoD reserving Iridium satellite time. Perhaps you would like to chew on the line "The Army, Navy and Air Force are testing ways to integrate the Iridium satellite network into their communications plans" for a while. It's in the first paragraph.
Here's a conspicuously obvious one titled "Army to Use Iridium Pagers."

It seems like with a little research (little meaning like, 20-30 seconds) would've shown you how wrong you really are. I suggest you do just that before posting next time.


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Iridium will be deorbited because it is the only way that they can take the satellites as a tax write off, something which I just find damn funny.

If Iridium showed us anything, it's that the pace at which telecommunications technology is advancing is leaps and bounds beyond the pace at which you can build and put up a satellite constellation. Consider what we thought 5 to 10 years ago about the state of communications today and the problem becomes pretty evident.

More importantly though, Iridium clearly demonstrated that the market for cell phones on the top of Mt. Everest is not enough to support the huge overhead of putting up and maintaining a satellite constellation. I'm fairly confident that if the market in backwater Tibet was strong enought to support $5k phone service, Bell-South would have already run cable. The reality is If you look at ICO's target market, "Maritime, Remote fixed, Handheld, Transportation, and Government", it's no different than Iridium's. What Iridium found was that the only sub-market of any of these willing to fork over the cash for there service was the handheld market for relief workers. If none of these markets materialized for Iridium, I'm not sure why they will for ICO.

http://www.spacedaily.com/spacecast/news/iridium-0 0d.html
What a waste ...

How exactly would a large satellite "clean up the junk?" Would it eat the dead satellites? You can't just clean them up. They have mass, they take up space. The only way you can get rid of them is to push them into the atmosphere. However, do you want to be the president of a company that starts pushing 17-ton satellites into the atmosphere hoping that they burn up on reentry or land in an ocean?

Why does everyone insist that Nature exists only on Earth? Does it not bother anyone that the 10,000 pieces of man-made debris surrounding the earth looks like this? That the University of Chicago and NASA launched a satellite in January 1999 to monitor the debris? That an international committee(the Inter-Agency Space Debris Coordination Committee, of which NASA, the European Space Agency, and the Chinese Space Agency are a part) has been formed in order to manage the garbage? That each piece of debris, moving at tens of thousands of km/h, poses a threat to future satellites? I'm sure people would care if we started trashing the moon, but that's even farther away. Just because it's vacuum doesn't mean it's not worth taking care of.

enmity.

Spacedaily claims, that there could be some problems
with the descent engine.

That could explain, why the two ballistic
devices didn't phone home, despite they would use
their own transmitters.
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