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Model Forum / General / Rockets / February 2008Spy satellite - a rant
Here's what really angers me about the affair. In the news, the satellite is reportedly going to "fall out of orbit". The Arizona Republic reports "Uncontrolled U.S. spy satellite plummets out of orbit". Others say "Navy to shoot down spy satellite". So why am I upset? Because things DON'T FALL OUT OF ORBIT! As long as an object has suffecient velocity and altitude, it will stay in orbit. The Moon is in orbit around the Earth; The Earth (and other planets) is in orbit around the Sun. None of these will "fall out of orbit". What's the problem then? Things will stay in orbit as long as they have suffecient velocity and altitude. Reduce either of these and the object will re-enter the atmosphere. You can have an orbit that is not circular; the low point (perigee) may come below the edge of the Earth's atmosphere. A side note; the Earth's atmosphere is not at a constant altitude from the Earth, just as the Earth's surface is not flat. Many things can affect this - sun activity, weather on Earth, and other things. Once the object comes withing the fringes of the atmosphers, it will slow down due to drag. Once it's velocity drops below a certain point, the orbit will significanly enter the Earth's atmosphere. When this happens, drag will exponentially reduce the velocity slowing the object even more. Additionally, the atmosphere will heat the object. It still has *considerable* velocity and the heating will increase as the object slows and drops further into thicker and thicker atmosphere. At some point the forces of drag and temerature will cause mechanical stresses on the object enough to cause it to undergo structural failure and break up. The temperature will increase to the point that the materials will beging to burn. This is what makes shooting stars so fun to watch. Why is the Navy trying to shoot the satellite down then? They're not trying to shoot it down. It would be extremely difficult to reducce the velocity of the satellite enough to cause it to slow down and enter the atmosphere. What they're trying to do is to break apart the satellite. The satellite contains hazardous materials that could prove harmful or fatal if people came into contact with them. Remember the shuttle Columbia disaster? Many pieces survived the trip through the atmosphere, including a hydrazine tank. The Navy hopes to break the satellite up and destroy fuel/propellant tanks and major structural parts before the hit the ground. And that's my rant. Please excuse any typos, My keyboard seems to be sticking and kickinng out ddouble letters att random. > The satellite contains hazardous materials that could prove harmful or > fatal if people came into contact with them. Remember the shuttle > Columbia disaster? Many pieces survived the trip through the atmosphere, > including a hydrazine tank. The Navy hopes to break the satellite up and > destroy fuel/propellant tanks and major structural parts before the hit > the ground. That's the party line, anyway. I suspect they are far more worried about their secret squirrel technology than about the welfare of anybody on the ground.. Kevin O > Here's what really angers me about the affair. In the news, the satellite > is reportedly going to "fall out of orbit". The Arizona Republic reports [quoted text clipped - 5 lines] > The Moon is in orbit around the Earth; The Earth (and other planets) is > in orbit around the Sun. None of these will "fall out of orbit". Things fall out of orbit all the time. A spy satellite is in Low Earth Orbit and I've got news for you, they don't have to come down to reach the fringes of the atmosphere, they're already in it.. They may be plenty high up there but there's still a very thin atmosphere which causes aero drag and slows LEO satellites. As their speed decreases, their orbit decays. This is why there is fuel on this satellite just like why there are boosters on the Space Station, it is in Low Earth Orbit and must be reboosted regularly to prevent it's orbit decaying to the point where it reenters and burns up. You said it yourself, sufficient velocity and altitude. In LEO the velocity is constantly being reduced by the thin atmosphere. The satellite in question had engines to be able to reboost and maintain it's orbit after aero drag had slowed it down. But it had a major failure shortly after being placed in orbit. So it's orbit has been decaying for a year now and it's getting close to reentry. Additionally, the fuel tank is still full because it died so soon after it was launched. The fuel by the way is hydrazine, a particularly nasty substance. In the cold of space, the hydrazine fuel is normally kept liquid by electric heaters. With a complete electrical failure, the hydrazine fuel is now a solid chunk of hydrazine ice. The fear is that this solid chunk of hydrazine increases the structural integrity of the fuel tank to the point where it could survive a reentry causing a chemical hazard in the impact site. So what they want to break up is the frozen hydrazine fuel tank. If it's broken out of the tank, the hydrazine ice particles will outgas like micro-comets. The plan has nothing to do with slowing down the satellite but to prevent a solid chunk of toxic fuel smashing into a possibly populated area. The difference with the Columbia hydrazine tank is that the fuel in it was still liquid so it didn't have the structural integrity of the hydrazine ice. Plus they were at the end of their mission and there was little fuel left but the satellite died shortly after being launched and it's tank has enough fuel to reboost the satellite for many years. Next time, try ranting on a subject that you know something about. >> Smaug the Destroyer swz >> So why am I upset? Because things DON'T FALL OUT OF ORBIT! > > Things fall out of orbit all the time. snip... > You said it yourself, sufficient velocity and altitude. Oh! So you *do* agree with me! I repeat for those of you like Whosplat that moves his lips while watching cartoons on TV THINGS DO NOT FALL OUT OF ORBIT. They are NOT in areodynamic flight. They are not held up by air! They are totally under the influence of gravity until an outside force acts upon them. An object in orbit around the Moon will remain in orbit forever (unless acted upon by outside forces such as solar radiation or solar wind) because there is no atmosphere to affect it. In fact there are many (accurate) science fiction stories about things deliberatly or accidently put in orbit that come around again to their point of origin. > Next time, try ranting on a subject that you know something about. Next time try getting YOUR facts right. Iky Newton knows a lot more than you ever will. >> Things fall out of orbit all the time. > snip... >> You said it yourself, sufficient velocity and altitude. >> > Oh! So you *do* agree with me! The problem is the satellite doesn't have sufficient altitude to keep it out of the very thin atmosphere. The atmosphere that causes it to imperceptably slow down and eventually causes the orbit to decay to the point of reentry. This has been happening to things thrown into orbit since we first started orbiting objects. > THINGS DO NOT FALL OUT OF ORBIT. > They are NOT in areodynamic flight. They are not held up by air! [quoted text clipped - 5 lines] > wind) > because there is no atmosphere to affect it. In But this satellite is not in orbit around a moon with no atmosphere. It is in orbit around the earth and is acted upon by the very thin atmosphere that exists at the altitude that Low Earth Orbiting satellites occupy. While it's not being held up by aerodynamic forces, there are aero forces acting upon it because there is a very thin atmosphere there. If things don't fall out of orbit, tell me where Sputnik 1 is. Or Skylab. Look it up dipshit. >> Next time, try ranting on a subject that you know something about. >> > Next time try getting YOUR facts right. Iky Newton knows a lot more than > you ever will. I've got my facts right and Newton would agree that it doesn't take much air to impart a force. Something about every action having an equal and opposite reaction. A single molecule striking the satellite will slow it down a tiny amount. And there's more than a single molecule at the altitude of Low Earth Orbit. By the way, I happen to be an engineer on the NASA Space Station and know more about orbital mechanics and aero effects on orbiting vehicles than you know about spy satellites. But I guess science fiction is more glamorous than science fact. >>> Things fall out of orbit all the time. >> snip... [quoted text clipped - 7 lines] > the point of reentry. This has been happening to things thrown into > orbit since we first started orbiting objects. Just because you restate what I've said doesn't mean you have any intelligence. > But this satellite is not in orbit around a moon with no atmosphere. > It is in orbit around the earth and is acted upon by the very thin [quoted text clipped - 3 lines] > thin atmosphere there. If things don't fall out of orbit, tell me > where Sputnik 1 is. Or Skylab. Read what I've posted. You seem to be able to understand the English language. Are you learning it as a second or third language? >Look it up dipshit. Oh, and you were doing *so* well up to this point. Ad hominum attacks make your point most eloquently! > By the way, I happen to > be an engineer on the NASA Space Station and know more about orbital > mechanics and aero effects on orbiting vehicles than you know about > spy satellites. Such claims are so easy to make in the annonimity of teh intrawebs. Does your daddy know you're using his computer? <snip of nonsense> Your point was that things don't fall out of orbit. Read about why Skylab reentered here http://en.wikipedia.org/wiki/Skylab . In particular, read this snip from that page: Increased solar activity, heating the outer layers of the Earth's atmosphere and thereby increasing drag on Skylab, led to an early reentry at approximately 16:37 UTC 11 July 1979. Notice it talks about drag on Skylab. Hmmm, where'd that come from? Believe what you want, who cares. > <snip of nonsense> > [quoted text clipped - 9 lines] > > Believe what you want, who cares. You apparently do not have the capacity to understand or comprehend what you read. This is EXACTLY what I said in my posts from the beginning. Once more, from the top, this time with feeling: "What's the problem then? Things will stay in orbit as long as they have suffecient velocity and altitude. Reduce either of these and the object will re-enter the atmosphere. You can have an orbit that is not circular; the low point (perigee) may come below the edge of the Earth's atmosphere. A side note; the Earth's atmosphere is not at a constant altitude from the Earth, just as the Earth's surface is not flat. Many things can affect this - sun activity, weather on Earth, and other things. Once the object comes withing the fringes of the atmosphers, it will slow down due to drag. Once it's velocity drops below a certain point, the orbit will significanly enter the Earth's atmosphere. When this happens, drag will exponentially reduce the velocity slowing the object even more. Additionally, the atmosphere will heat the object. It still has *considerable* velocity and the heating will increase as the object slows and drops further into thicker and thicker atmosphere. At some point the forces of drag and temerature will cause mechanical stresses on the object enough to cause it to undergo structural failure and break up. The temperature will increase to the point that the materials will beging to burn. This is what makes shooting stars so fun to watch." While I suspect that there really is a need to blast that fuel tank to atoms I can't help but think that the boys in the Pentagon are kinda itchen to try some of their new-fangled ABM technology. What better way to put the FOG in to the ChiComs and the Red Koreans and while we're at it, give a techno-finger to the Ruskies too. I say this tongue in cheek but dang, after 6 years with NORAD and SAC way back in the Cold War I have seen too much to be naive.  SignatureR J Talley Teacher/James Madison Fellow "What? Me Worry? Alfred E Newman > While I suspect that there really is a need to blast that fuel tank to atoms > I can't help but think that the boys in the Pentagon are kinda itchen to try [quoted text clipped - 3 lines] > after 6 years with NORAD and SAC way back in the Cold War I have seen too > much to be naive. It's far from just blasting the fuel tank... There's stuff on that sat that the gov doesn't want us to know about.. I wonder what powers the thing? Might it not be solar? Also, they want to show that they can shoot it down.. Make other countries think they can shoot down anything.. (my bet is they confuse English and metric again and they'll hit a sat for Air America instead!) In reality, things like Skylab, and were bigger, and probably had more fuel, but were allowed to just "burn up", and had no effect other than inspiring "Dead Like Me" where a toilet seat killed the main character! The real question is, what if they can't shoot it down and it lands on land? That's when it could get very interesting....... >> While I suspect that there really is a need to blast that fuel tank to atoms >> I can't help but think that the boys in the Pentagon are kinda itchen to try [quoted text clipped - 8 lines] > There's stuff on that sat that the gov doesn't want us to know about.. > I wonder what powers the thing? Might it not be solar? Many satellites and expended booster stages fall from orbit every year. A good number of them have hydrazine on board, and we've never taken action to protect the public from them. Probably half of the dozen or so space junk items that reentered in 2007 had hydrazine on board. Not counting the shuttle, which has several tanks of it. Nope, the reason for shooting this one down was absolutely the classified technology on board. Normally they could just deorbit the thing so that it burns up over the ocean, and the remains are miles under water. But with no control, they couldn't take the chance that it might land somewhere that others might find it. No reason for nuke power on an earth orbit satellite. We use RTGs for probes like V*GER and Cassini because they are too far from the sun. > Also, they want to show that they can shoot it down.. Make other > countries think they can shoot down anything.. (my bet is they confuse > English and metric again and they'll hit a sat for Air America instead!) A rather impressive hit. If we really hit it. How can we tell they did what they said. If they lied about the reason, they could just as easilly lie about the results. That's the problem with a government that can't be trusted. Sort of makes you wonder what really happened to flight 93? SignatureBob Kaplow NAR # 18L >>> To reply, there's no internet on Mars (yet)! <<< Kaplow Klips & Baffle: http://www.nira-rocketry.org/Document/Phantom4000.pdf www.encompasserve.org/~kaplow_r/ www.nira-rocketry.org www.nar.org Sir, if I was building a weapon of mass destruction, you wouldn't be able to find it. > Many satellites and expended booster stages fall from orbit every year. A > good number of them have hydrazine on board, and we've never taken action to [quoted text clipped - 17 lines] > > Sort of makes you wonder what really happened to flight 93? Bob, with all that conspiricy stuff, your starting to sound like that Brad Gruth character...(:-) Not to fear though, the Navy knocked the sh.t out of it; no piece bigger than a football survived. So much for the thousand pound hydrazine ice cube. BTW, screw the Ruskies and the chinks, if they don't like it... Fred >BTW, screw the Ruskies and the chinks, if they don't like it... Wrong newsgroup for that. ;-) > So why am I upset? Because things DON'T FALL OUT OF ORBIT! As long as > an object has suffecient velocity and altitude, it will stay in orbit. > The Moon is in orbit around the Earth; The Earth (and other planets) is > in orbit around the Sun. None of these will "fall out of orbit". Yeah, well, a headline of "Spy satellite orbit intersects ground. Navy to turn it into a swarm of microsatellites." just doesn't have the sort of pizazz that sells newspapers. Signatureroger ivie rivie@ridgenet.net >> So why am I upset? Because things DON'T FALL OUT OF ORBIT! As long as >> an object has suffecient velocity and altitude, it will stay in orbit. [quoted text clipped - 4 lines] > to turn it into a swarm of microsatellites." just doesn't have the sort > of pizazz that sells newspapers. (gasp!) You mean they sensationalize subjects just to sell the news? Say it ain't so Joe, say it ain't so! |
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