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Author Topic:   Spy satellite making uncontrolled reentry to be shot down by missile
MCroft04
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posted 01-26-2008 08:26 PM     Click Here to See the Profile for MCroft04   Click Here to Email MCroft04     Edit/Delete Message   Reply w/Quote
CNN is running a story about a spy satellite possibly carrying hazardous material that has lost power and headed to earth sometime in February or March. Keep your heads toward the sky.

Robert Pearlman
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posted 01-26-2008 08:53 PM     Click Here to See the Profile for Robert Pearlman   Click Here to Email Robert Pearlman     Edit/Delete Message   Reply w/Quote
The CNN version of the Associated Press' story is abbreviated. For a few more details, see the original: Disabled Spy Satellite Threatens Earth

Though even the longer version may not be entirely accurate...

The satellite, which no longer can be controlled, could contain hazardous materials, and it is unknown where on the planet it might come down, they said. The officials spoke on condition of anonymity because the information is classified as secret. It was not clear how long ago the satellite lost power, or under what circumstances.
The satellite is believed to be USA 193/NRO L-21, which was launched in Dec. 2006 but failed to deploy its solar panels (panels illustrated for reference).

Reuters reported in August of last year that L-21 had failed and was expected to eventually reenter.

Ben
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posted 01-26-2008 08:58 PM     Click Here to See the Profile for Ben   Click Here to Email Ben     Edit/Delete Message   Reply w/Quote
The satellite hobbyists over on See Sat have been tracking L-21 since its launch when things quickly appeared off-nominal (and the panels were never seen in photos). A late-February reentry prediction has been in the cards, so it matches.

Robert Pearlman
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posted 01-30-2008 01:22 AM     Click Here to See the Profile for Robert Pearlman   Click Here to Email Robert Pearlman     Edit/Delete Message   Reply w/Quote
Associated Press: AF General: Spy Satellite Could Hit US
Air Force Gen. Gene Renuart, who heads of U.S. Northern Command, told The Associated Press on Tuesday that the size of the satellite suggests that some number of pieces will not burn up as the orbiting vehicle re-enters the Earth's atmosphere and will hit the ground.

"We're aware that this satellite is out there," Renuart said. "We're aware it is a fairly substantial size. And we know there is at least some percentage that it could land on ground as opposed to in the water."

...Renuart added that, "As it looks like it might re-enter into the North American area," then the U.S. military along with the Homeland Security Department and the Federal Emergency Management Agency will either have to deal with the impact or assist Canadian or Mexican authorities.

Military agencies, he said, are doing an analysis to determine which pieces most likely would survive re-entry. But he cautioned that officials won't have much detail on where or when it will crash until it begins to move through the atmosphere and break up.

cspg
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posted 01-30-2008 04:37 AM     Click Here to See the Profile for cspg   Click Here to Email cspg     Edit/Delete Message   Reply w/Quote
a fairly substantial size
Yet it was launched aboard a Delta 2.

It makes you wonder the size of payloads aboard heavier launch vehicles like Delta 4 or Atlas 5 and if one of those were to fall back down to Earth...

Ben
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posted 01-30-2008 07:53 AM     Click Here to See the Profile for Ben   Click Here to Email Ben     Edit/Delete Message   Reply w/Quote
"A U.S. official confirmed that the spy satellite is designated by the military as US 193. It was launched in December 2006..."

Ben
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posted 02-04-2008 11:36 PM     Click Here to See the Profile for Ben   Click Here to Email Ben     Edit/Delete Message   Reply w/Quote
The New York Times on satellite observing and USA 193.

SpaceAholic
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posted 02-13-2008 11:30 PM     Click Here to See the Profile for SpaceAholic   Click Here to Email SpaceAholic     Edit/Delete Message   Reply w/Quote
Aviation Week reports the US is assessing the feasibility of an ASAT launch to interdict and destroy the satellite.

cspg
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posted 02-14-2008 12:08 AM     Click Here to See the Profile for cspg   Click Here to Email cspg     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by SpaceAholic:
Aviation Week reports the US is assessing the feasibility of an ASAT launch to interdict and destroy the satellite.
Also known as "See Beijing, we can do it too!"

Robert Pearlman
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posted 02-14-2008 11:34 AM     Click Here to See the Profile for Robert Pearlman   Click Here to Email Robert Pearlman     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by SpaceAholic:
Aviation Week reports the US is assessing the feasibility of an ASAT launch to interdict and destroy the satellite.
According to the Associated Press, they will indeed 'shoot it down'.
The Pentagon is planning to shoot down a broken spy satellite expected to hit the Earth in early March, The Associated Press has learned.

U.S. officials said Thursday that the option preferred by the Bush administration will be to fire a missile from a U.S. Navy cruiser, and shoot down the satellite before it enters Earth's atmosphere.

The officials spoke on condition of anonymity because the options will not be publicly discussed until a later Pentagon briefing.

Robert Pearlman
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posted 02-14-2008 12:47 PM     Click Here to See the Profile for Robert Pearlman   Click Here to Email Robert Pearlman     Edit/Delete Message   Reply w/Quote
Department of Defense release
Press Briefing On Reentry Of U.S. Satellite Announced

Ambassador James Jeffrey, assistant to the President and deputy national security advisor; Gen. James Cartwright, Joint Chiefs of Staff vice chairman; and Michael Griffin, NASA administrator, will conduct a press briefing in the DoD Briefing Room at 2:30 p.m. EST, Feb. 14, Pentagon Room 2E579 to discuss reentry of a U.S. satellite.
This briefing will be carried live on NASA TV.

Robert Pearlman
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posted 02-14-2008 02:52 PM     Click Here to See the Profile for Robert Pearlman   Click Here to Email Robert Pearlman     Edit/Delete Message   Reply w/Quote

Tanks, including those that held hydrazine fuel, recovered from shuttle Columbia

The U.S. Department of Defense plans to intercept a National Reconnaissance Office satellite just before it can reenter the Earth's atmosphere in an attempt to mitigate the public's risk from exposure to toxic fuel.

The satellite, known as NRO L-21 or USA 193, suffered a complete communications and control failure soon after reaching orbit in December 2006. It is now within two weeks of an uncontrolled reentry during which, left untouched, it has both the potential to deposit up to half of its 5,000 pound, bus-sized structure over populated areas and, of more concern, release its nearly full reserves of hydrazine gas. The toxic fuel is deadly to humans over sustained, significant exposure.

To address this risk, the Navy will position three of its Aegis guided missile cruisers in an undisclosed area of the northern Pacific, where sometime over the next seven to eight days depending on further tracking of the satellite, a modified Standard Missile 3 (SM-3) will be launched to intercept the spacecraft and break it and its hazardous fuel tank apart.

The timing of the launch will be coordinated to occur just before the satellite would naturally decay in its orbit, such that within one to two orbits later, fifty percent of the satellite debris will reenter, with the remainder following shortly thereafter.

The launch will be made after space shuttle Atlantis returns from the International Space Station and, if possible, at a "good time" in the orbit of the continuously-crewed outpost, according to NASA Administrator Michael Griffin.

The decision to take this action came as a result of another reentry: space shuttle Columbia in February 2003. Its hydrazine tank(s) survived and impacted the ground but as the reentry came at the end of the mission, most of the fuel had already been spent.

According to Griffin, taking action of any type results in either a neutral or positive effect. "Neutral is if we miss. Almost anything you do when it is barely in orbit, will cause it reenter. Almost nothing we can do to make it worse. Almost anything you can do here makes it better," he said.

Though three missiles are being deployed, this will be a "one-shot" attempt. Should the intercept miss, the Department of Defense believes it will have up to two days to assess the situation and if deemed favorable, try again. However, they are confident in success given the well-understood technology being used.

This is the first time a U.S. tactical missile has been used to intercept a spacecraft. It is not however, the first time the military has used such weapons to strike at an object returning through the atmosphere.

The Department of Defense will work with NASA to determine the best time to stage the launch, as to reduce the risk to space, air and land assets.

A Standard Missile-3 (SM-3) launch (Photo: Missile Defense Agency)

spaceman1953
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posted 02-14-2008 08:39 PM     Click Here to See the Profile for spaceman1953   Click Here to Email spaceman1953     Edit/Delete Message   Reply w/Quote
What "humors" me, is that a day or two ago, when "they" first announced that this satellite was "de-orbiting", it was of no concern...

Now it is the President that Ordered DOD to shoot it down... he did not say use one shot, he said shoot it down! So suddenly, at least publicly, there IS concern at the highest levels.

Now, the computer that failed and caused this whole ruckus... who made that? And do we get a refund?

Cheers, and practice your ducking!

Robert Pearlman
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posted 02-14-2008 10:01 PM     Click Here to See the Profile for Robert Pearlman   Click Here to Email Robert Pearlman     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by spaceman1953:
...he did not say use one shot, he said shoot it down!
Actually, that's not what was said. Gen. Cartwright specifically stated that it was "one shot".

Though they will have three missiles staged, the only reason for the other two (at least at first, before a one to two day assessment period) is in the case of a launch failure.

Further, I think if you go back and read what the military said about the satellite before today's announcement, they never said it was of "no concern". They (correctly) stated that there was "at least some percentage that it could land on ground as opposed to in the water."

So they haven't been completely unreasonable in their statements to date.

(And the Pentagon referred reporters to the NRO when they were questioned about who made the satellite and who was at fault. To my knowledge, the NRO has yet to respond.)

Jerry Brouillette
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posted 02-14-2008 10:06 PM     Click Here to See the Profile for Jerry Brouillette   Click Here to Email Jerry Brouillette     Edit/Delete Message   Reply w/Quote
Great posts on this subject so far and I suspect many more to come as the whole thing unfolds.

Without getting into political reasons or the timing in the decision to try and 'down' this thing... I say why the hell not. I bet we get it!

Robert Pearlman
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posted 02-14-2008 11:19 PM     Click Here to See the Profile for Robert Pearlman   Click Here to Email Robert Pearlman     Edit/Delete Message   Reply w/Quote
Additional coverage:

spaced out
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posted 02-15-2008 01:54 AM     Click Here to See the Profile for spaced out   Click Here to Email spaced out     Edit/Delete Message   Reply w/Quote
Seems to me like they're just taking a good opportunity to try-out their satellite-intercept technology for real without causing any international upset.

cspg
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posted 02-15-2008 04:33 AM     Click Here to See the Profile for cspg   Click Here to Email cspg     Edit/Delete Message   Reply w/Quote
It also comes at the time Russia and China (not really a surprise here) in conference talks here in Geneva are proposing a new space treaty banning space-based weapons! The U.S. objects to such treaty (after China's little experiment last year, no surprise again!).

gliderpilotuk
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posted 02-15-2008 08:35 AM     Click Here to See the Profile for gliderpilotuk   Click Here to Email gliderpilotuk     Edit/Delete Message   Reply w/Quote
When the military spokesman describes the effect of the fuel as "similar to chlorine" and the likely severe danger area to be "no larger than 2 football fields", you have to wonder whether this is just a good excuse to test the not-so-far-so-successful ABM technology.

Robert Pearlman
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posted 02-15-2008 09:33 AM     Click Here to See the Profile for Robert Pearlman   Click Here to Email Robert Pearlman     Edit/Delete Message   Reply w/Quote
A transcript of yesterday's press briefing is now available via the U.S. Department of Defense website.

SpaceAholic
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posted 02-15-2008 10:33 AM     Click Here to See the Profile for SpaceAholic   Click Here to Email SpaceAholic     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by gliderpilotuk:
...you have to wonder whether this is just a good excuse to test the not-so-far-so-successful ABM technology.
Actually we have had 11 of 13 successful target intercepts during developmental / operational testing of the SM3...

jeffbassett
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posted 02-15-2008 02:20 PM     Click Here to See the Profile for jeffbassett   Click Here to Email jeffbassett     Edit/Delete Message   Reply w/Quote
My understanding is the real issue for shooting this is the technology on this satellite. The technology on this is some of the best high imaging hardware available and there is a huge concern that if it landed that other nations might get their hands on it. So that is the real reason this has gained such a high priority. With the issue of space junk and debris from the China anti-sat test, there is a huge concern for the secondary issue of debris being scattered about with this shoot down. The US and other nations were extremely upset about the amount of material from China's test. So it's with a bit of uneasiness that we do have to now implement a shoot down ourselves. There are quite a few potential problems from taking this out with a missile (space junk produced, further radioactive fall out, showing of anti-sat technology we are capable of).

There are a few spins on this, showing our capabilities to China for show, along with the fuel issue. Bottom line, it comes down to not letting the technology fall into the wrong hands.

Robert Pearlman
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posted 02-15-2008 02:30 PM     Click Here to See the Profile for Robert Pearlman   Click Here to Email Robert Pearlman     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by jeffbassett:
My understanding is the real issue for shooting this is the technology on this satellite.
For what it is worth, General Cartwright directly denied this during yesterday's briefing:
I've also, like you, read the blogs. This is -- there's some question about the classified side of this. That is really not an issue. Once you go through the atmosphere and the heating and the burning, that would not be an issue in this case. It would not justify using a missile to take it and break it up further.

SRB
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posted 02-15-2008 03:01 PM     Click Here to See the Profile for SRB   Click Here to Email SRB     Edit/Delete Message   Reply w/Quote
One of the real problems with the Chinese blowing up its satellite is the hundreds (thousands) of pieces of space debris it caused. Is it fair to assume that this will not happen when we blow up our satellite because it is so close to re-entry that all the new pieces will re-enter soon too?

Robert Pearlman
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posted 02-15-2008 03:09 PM     Click Here to See the Profile for Robert Pearlman   Click Here to Email Robert Pearlman     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by SRB:
Is it fair to assume that this will not happen when we blow up our satellite because it is so close to re-entry that all the new pieces will re-enter soon too?
That is how it was explained by General Cartwright:
On the orbit side, in space, what we're attempting to do here is to intercept this just prior to it hitting the Earth's atmosphere. That does two things for us. It reduces the amount of debris that would be in space -- so in this case, what we're looking for it to try to have the debris, over 50 percent of it within the first two orbits or the first 10 or 15 hours would be de-orbited. The second piece here is looking at other, unmanned bodies in space, in low-Earth orbit, and the space station to make sure that we did not increase the risk to other bodies in space. So that was a criteria we're trying to understand.

Robert Pearlman
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posted 02-15-2008 07:19 PM     Click Here to See the Profile for Robert Pearlman   Click Here to Email Robert Pearlman     Edit/Delete Message   Reply w/Quote
AP: Satellite Shootdown Plan Began in Jan.
Long before the public learned in late January that a damaged U.S. spy satellite carrying toxic fuel was going to crash to Earth, the government secretly assembled a high-powered team of officials and scientists to study the feasibility of shooting it down with a missile.

The order to launch the crash program came Jan. 4, according to defense officials who described Friday how it came to fruition for a final go-ahead decision by President Bush this week. The officials spoke to The Associated Press on condition they not be identified because of the sensitivity of the work.

The initial order was twofold: Assess whether shooting down the satellite with a missile was even possible, and at the same time urgently piece together the technological tools it would take to succeed...

The spacecraft contains 1,000 pounds of hydrazine in a tank that is expected to survive re-entry and a fuel tank liner made of beryllium.

FEMA has prepared a guide for emergency responders that includes information about hydrazine and beryllium. The agency warns officials not to pick up any debris or provide mouth-to-mouth resuscitation to anyone who has inhaled hydrazine or beryllium.

issman1
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posted 02-15-2008 07:27 PM     Click Here to See the Profile for issman1     Edit/Delete Message   Reply w/Quote
According to the Russian military, the satellite in question has a nuclear fuel source. What is the chance of this dispersing within the atmosphere over populated areas if blown-up? And any chance it can be seen from the UK like I was able to view Atlantis/ISS recently?

spaceman1953
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posted 02-15-2008 07:40 PM     Click Here to See the Profile for spaceman1953   Click Here to Email spaceman1953     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by Robert Pearlman:
A transcript of yesterday's press briefing is now available via the U.S. Department of Defense website.
Thanks for the reply to my posting and this link...

Everyone interested should take the few minutes to read through this briefing... it answers a lot of questions and seems, for the most part, to be refreshingly frank.

I do wish we could learn the ship(s) involved.

jeffbassett
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posted 02-15-2008 07:46 PM     Click Here to See the Profile for jeffbassett   Click Here to Email jeffbassett     Edit/Delete Message   Reply w/Quote
Yep, definitely there will be a spin on this. But a shoot down is unprecedented for any case like this. Large US objects have come down in the past. And yes, there is an issue of breaking up the reactor. You may remember the Canadian fall in the 70's and the concerns and clean up that followed. The accuracy is hard enough hitting it, to do so accurately to the tanks will be an incredible challenges as the Pentagon has reported. So again, the real issue to look at here is why it is so important to have to shoot this down. Absolutely, it is the technology that is at issue here.

As far as the issue of the actual shoot down, from the AP:

Other details about the missile and the targeting were not immediately available. But the decision involves several U.S. agencies, including the Department of Homeland Security and the State Department...

Shooting down a satellite is particularly sensitive because of the controversy surrounding China's anti-satellite test last year, when Beijing shot down one of its defunct weather satellites, drawing immediate criticism from the U.S. and other countries.

A key concern at that time was the debris created by Chinese satellite's destruction -- and that will also be a focus now, as the U.S. determines exactly when and under what circumstances to shoot down its errant satellite.

The military will have to choose a time and a location that will avoid to the greatest degree any damage to other satellites in the sky. Also, there is the possibility that large pieces could remain, and either stay in orbit where they can collide with other satellites or possibly fall to Earth.

It is not known where the satellite will hit. But officials familiar with the situation say about half of the 5,000-pound spacecraft is expected to survive its blazing descent through the atmosphere and will scatter debris -- some of it potentially hazardous -- over several hundred miles. The officials spoke on condition of anonymity because of the sensitivity of the matter.

Robert Pearlman
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posted 02-15-2008 08:04 PM     Click Here to See the Profile for Robert Pearlman   Click Here to Email Robert Pearlman     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by issman1:
According to the Russian military, the satellite in question has a nuclear fuel source.
The Russian military has said that it "could" have nuclear assets aboard, not that it "has". They're speculating based on the apparent lack of solar panels, without acknowledging that a failure to deploy its solar panels could have created the present situation.

Robert Pearlman
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posted 02-15-2008 08:05 PM     Click Here to See the Profile for Robert Pearlman   Click Here to Email Robert Pearlman     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by spaceman1953:
I do wish we could learn the ship(s) involved.
According to the Associated Press (as linked above), the USS Lake Erie, USS Decatur and USS Russell.

Robert Pearlman
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posted 02-15-2008 08:08 PM     Click Here to See the Profile for Robert Pearlman   Click Here to Email Robert Pearlman     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by jeffbassett:
But a shoot down is unprecedented for any case like this. Large US object have come down in the past. And yes, there is an issue of breaking up the reactor.
There are no credible reports of a reactor. As for precedent, there has never been a case of 1,000 pounds of frozen hydrazine reentering in a tank that is known to be able to survive a fall to the ground.

At best, the hydrazine provided an opportunity to conduct an ABM test.

jeffbassett
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posted 02-17-2008 04:46 PM     Click Here to See the Profile for jeffbassett   Click Here to Email jeffbassett     Edit/Delete Message   Reply w/Quote
There is no absolute way to verify whether or not a reactor is on board this satellite. The Soviets use a system that boost the satellite up in a higher orbit so that the life span of the radioatic isotopes is not a danger when it falls, or technology of the future will allow for a reliable retrieval.

The US has had to rely on reactors for quite a long time on probes on the solar system but does not like to talk about it at all due to the issue of conservationist / enviromentalist that have raised a huge stink about other reator powered launches. With the SDI program, it was one of the main ways objections were raised about progressing with program at the time. But it has been a fact that any large probe/unit with large power needs cannot be sustained on just solar power alone. Not to say its an absulute on this, but a system this size...

The Canadian fall in the 70's is an example of one such system failing and landing. The Slave lake fall has only 1% of the radioactive material recovered. A large part of it still lays undiscovered in the remote area. If the US does have a reactor, it would make sense to try to aim for a pacific intercept at the lowest orbit possible and fall in the ocean rather over a land mass.

Robert Pearlman
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posted 02-17-2008 04:58 PM     Click Here to See the Profile for Robert Pearlman   Click Here to Email Robert Pearlman     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by jeffbassett:
The US has had to rely on reactors for quite a long time on probes on the solar system but does not like to talk about it at all due to the issue of conservationist / environmentalist that have raised a huge stink about other reactor powered launches.
I think I see a potential area of confusion: U.S. planetary probes do not use reactors, they (sometimes) use radioisotope thermoelectric generators (RTG), a type of battery based on the heat generated from radioactive decay. RTGs are not reactors.

In fact, the only spacecraft ever launched by NASA with a reactor was SNAP-10A in 1965. Like the Soviet system you cite, its core was ejected into a much higher orbit.

micropooz
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posted 02-17-2008 05:40 PM     Click Here to See the Profile for micropooz   Click Here to Email micropooz     Edit/Delete Message   Reply w/Quote
Hey gang, we need to set a couple of things straight here:

1) With the current state of technology, the only time that nuclear reactors or RTG's are worth sending into space is if the payload is going beyond the asteroid belt, where solar cells are no longer effective. Reactors and RTG's were more attractive decades ago when solar cells were much less efficient than today, and there were less restrictions (eg - less cost) associated with nuclear power. That makes it highly doubtful that this current technology earth orbiting satellite has any kind of nuclear material aboard.

2) The news media, and even parts of this thread, make it sound like the Navy is going to blast this satellite out of the sky (eg -"shoot it down"). They make it sound like the movies of WWII airplanes being hit and spiraling straight down in flames. The reality is that the satellite is coming down on its' own due to atmospheric drag. The shot will try to break it apart a few orbits before it naturally re-enters, so that the pieces (including the tank full of hydrazine) have a better chance of vaporizing during re-entry.

This is probably not news to a lot of you, but I just wanted to make sure that all of us are clear on some of the physics here.

cspg
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posted 02-18-2008 01:22 AM     Click Here to See the Profile for cspg   Click Here to Email cspg     Edit/Delete Message   Reply w/Quote
Reuters: China concerned by U.S. satellite missile plan
China is concerned by U.S. plans to shoot down an ailing spy satellite and is considering what "preventative measures" to take, the Foreign
Ministry said on Sunday.

"The Chinese government is paying close attention to how the situation develops and demands the U.S. side fulfill its international obligations and avoids causing damage to security in outer space and of other countries," spokesman Liu Jianchao said.

As if the Chinese government was in any position to make such statement...

jeffbassett
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posted 02-18-2008 01:08 PM     Click Here to See the Profile for jeffbassett   Click Here to Email jeffbassett     Edit/Delete Message   Reply w/Quote
Yep, understand the physics on this absolutely. Spy satellites tend to be designed now to be unobtrusive, to not give away visually any thing more of the make up than possible. As secret as these are, a good telescope can give governments an idea of whats up there. For this to be as large as it is, either you are looking at quite a bit of electronics and or a huge amount of fuel.

As for the physics of the break up, the physics in a blast are quite interesting in orbit. You are going to be looking at material being blasted in all directions. This is what has made the China test such a huge problem. The amount of material blasted into several orbital paths and heights makes it a huge head ache for other objects in orbit. Such a strike is not done lightly and considering the fallout, physically and politically, you have to know quite a bit is involved with this having to be brought down.

It will be an interesting to see as it happens and how it all plays out.

Agreed, China has no valid voice of concern at this point given what they have done unless they had no concept to the damage they were going to do with the debris.

Philip
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posted 02-18-2008 01:41 PM     Click Here to See the Profile for Philip   Click Here to Email Philip     Edit/Delete Message   Reply w/Quote
I'm a bit amazed that anti-satellite missiles can be fired to such altitudes from the ground (sea) up. I remember that the US Air Force had anti-satellite missiles but these were fired from an F-15 fighter jet flying at maximum altitude... Guess that mil technology evolves very fast!

Robert Pearlman
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posted 02-18-2008 03:22 PM     Click Here to See the Profile for Robert Pearlman   Click Here to Email Robert Pearlman     Edit/Delete Message   Reply w/Quote
The Cosmic Mirror:
Satellite attack planned for Feb. 21 - right during the lunar eclipse?
A Notice to Airmen has been issued closing a zone near Maui for air traffic on the morning of Feb. 21 from 2:30 to 5:00 UTC - and the to-be-hit satellite USA 193 is crossing that very zone around 3:30 UTC. Furthermore it has been noted that this is during totality of the total lunar eclipse that night which may aid the optical tracking of faint fragments.
The blog entry is slightly incorrect when it (later) reads "Atlantis will land on Feb. 20 no matter what" as NASA has made it clear that if weather or technical conditions are not acceptable for a Feb. 20 landing, they are are under no DoD pressure not to land on Thursday (or if need be, Friday, should they choose so).

MCroft04
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Posts: 1219
From: Smithfield, Me, USA
Registered: Mar 2005

posted 02-18-2008 07:36 PM     Click Here to See the Profile for MCroft04   Click Here to Email MCroft04     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by Robert Pearlman:
...they are are under no DoD pressure not to land on Thursday (or if need be, Friday, should they choose so).
Interesting. Robert knows best but I just saw an interview with Leroy Cain who said they would land Wednesday, either at KSC or Edwards.


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