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February 14, 2008

The sky is falling

Posted: 04:05 PM ET

The Pentagon announced today that sometime in the next few weeks a U.S. Navy ship will shoot down a failed National Reconnaisance Office spy satellite.

We don't know much about the satellite in question except that it launched on December 14, 2006 and it failed several hours after entering orbit.

It was apparently designed with the ability for a controlled de-orbit, but since command and control has been lost, that's now out.

Expert analysis indicates about half of the 5000-pound satellite would survive atmospheric reentry. It has a full tank of noxious hydrazine rocket fuel aboard, which would vent if the tank survived and hit the ground. Anyone within two football field's distance would be sickened by the fumes.

The U.S. Navy will fire one SM-3 missile from a ship in an effort to hit the satellite just as it grazes the atmosphere. By waiting until it is just about to re-enter before blasting it, they intend for most of the debris to quickly fall out of orbit and burn up ... most of it within hours, almost all of it within days or weeks.

This is not the first time a government has shot down a satellite. A decision to shoot down the satellite is sure to cause controversy in the aerospace community, as it would result in a massive amount of additional space junk in low earth orbit.

In January 2007, China used a land-based missile to destroy a 2,200-pound weather satellite called Fengyun-1C that was orbiting 528 miles above Earth.

That impact left more than 150,000 pieces of debris floating around he Earth, the NASA Orbital Debris Program Office estimates. The space agency characterizes nearly 2,600 pieces s "large," meaning greater than 10 cm (4 inches) across.

China is responsible for 42 percent of all satellite debris in orbit as of January 1, most of it from that Fengyun-1C satellite. NASA has called it the worst satellite breakup in history.

Kate Tobin, Senior Producer, CNN Science & Technology

Filed under: NASA • Space


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Clint Stephenson   February 14th, 2008 5:39 pm ET

I believe the US is shooting down the spacecraft as an exercise and demonstration in missile defense techniques.


Patrick, UAlbany   February 14th, 2008 8:56 pm ET

Maybe I'm the only person that sees it in this perspective, but this strikes me as a great opportunity to test out any anti satellite technology the military may have been working on. I have a hard time believing they would miss the chance to test something out. I probably sound like a conspiracy theorist but you'd be hard pressed to tell me they don't have anything like that cooking up in their think tank ovens. Let's just hope no one gets hurt.


David Seachrist   February 14th, 2008 9:12 pm ET

Hmmm. I did not hear president bush list SDI (Satellite Debris Initiative) as one of his reasons for expanding the patriot act spy legislation.


Oscar Hasten   February 14th, 2008 9:29 pm ET

Well, thank god this opportunity to test a missile/anti satellite system came up. ahem.


Paul W   February 14th, 2008 9:50 pm ET

A question that came to mind shorty after reading this article is, what exactly is a controlled de-orbit?

I've never heard of such a procedure.

So it's not a matter of an inability to execute a "controlled de-orbit".
The fact is the satelite is inoperable as a whole?

Surprising to me, I'm no expert but this is the first time that I heard of a U.S. reconnaisance satelite failing. Interesting none the less.


Chris Maldonado   February 15th, 2008 12:33 am ET

Well, that will about make us even with China on the amount of artificially produced space debris that this would create. Further, it will also one-up them via demonstration of U.S. anti-satellite capability.


Alan Anderson   February 15th, 2008 6:28 am ET

Would it not be better to have one piece of debris falling rather than several thousand which could have a devastating affect on commercial aviation as we would not know when or where there would be an impact with a plane, due to the random nature of debris re-entry????


Monique   February 15th, 2008 9:25 am ET

I say... stop sending objects outside of your atmosphere anyway. Mind your own business and we will no longer have these security issues. This is the "REAL" National Security issue.


Robert: NY   February 15th, 2008 9:55 am ET

Does anyone else consider the fact that if Homeland Security is involved that there is a good chance this satellite was a stationary satellite monitoring the United States Borders? In late October a friend of mine spotted a satellite off the North East Coast of the US. After looking at it with a scope it remained stationary for the evening at a azimuth of approximately 40 degrees and an altitude of less than 20 degrees. The satellite wabbled more than others and was much brighter. I am going to watch it for the next couple of nights to see if it, well let's say, has an accident. I know that the government has said it was launched in December. It is the same government that told me there were WMDs in Iraq.


Grant K.   February 15th, 2008 10:06 am ET

From what I had learned and been involved with....

1) Main reason for this is to save lives. If the path of de-orbit and re-entry has better than a 67% of hitting a USA city or within 75 miles of a cities power supply/water. Then we should react or if another country is asking us to assist them. This is good protocall.

2) Second is just a good test for our testing of a class 3 missle.

FYI – in the state of Oregon in a crater from a 4.5 pound space rock that left a large hole in the ground..... this satelite is the sie of a bus... hum... hum.... that well make a very large hole, don't you think?


Incredulous Missourian   February 15th, 2008 10:08 am ET

Excuse me, but the cover story is what? A substance chosen specifically for efficient and effective explosive combustion is likely enough to survive a 5000 degree re-entry fireball? There's a 1% chance of even hitting a populated area, and at that it only affects an area 600 yards in radius, and then only 'sickening' those who breathe it in long enough? Even Forrest Gump would have a little trouble buying this one.


sandy   February 15th, 2008 10:53 am ET

Just maybe this is no "conspiracy" blah blah blah. It could be
that the satellite just totally failed. If you read all the articles, then
it makes sense that it has to be shot down. I just heart on CNN
that there is a 1 in 1zillion chance of anyone being hit by falling
space debris on earth. What irritates me is tht China is responsible
for 42% of floating space debris over 4" big in orbit. Why has
no one addressed this issue?


HT   February 15th, 2008 10:55 am ET

I believe they said if the satellite was to be "shot", the only reason was due to the fuel tanks ability to survive reentry. (fuel is the only concern) If shot, the tank would explode and the fuel would either burn or most likely be left in space. The larger chunks were expected to burn up in the atmosphere.

I would assume deorbit is actually a controlled reentry, much like the space shuttle. I think they would be able to position the satellite and use its thrusters to bring it down, at least in an area that they wanted, but I am unsure on whether or not it would be in tact.


Justin K   February 15th, 2008 11:19 am ET

Paul,

A controlled de-orbit is when a satellite is directed towards reentry under human control and towards a specific area, to thus avoid any potential debris collisions. It's actually pretty self-explanatory. If a satellite cannot be boosted into a "graveyard" orbit, it will be brought back to Earth in a controlled manner.

Alan,
The hydrazine tank is nearly entirely full and frozen. If this came down in a populated area, thousands could be exposed to a very, very toxic substance. The administration has decided it is better to intercept the satellite and ensure that the tank is ruptured, than to risk the hydrazine coming down intact somewhere over North America. The intercept would also ensure that re-entering debris is smaller and much more likely to burn up long before reaching the altitude that commercial aircraft operate at.


Monique   February 15th, 2008 1:56 pm ET

Is there anyone else here who doesnt feel as if there is a definite issue of Homeland Security??? Really?


Richard   February 15th, 2008 2:26 pm ET

Several people above have said America wants to shoot this satellite down to test its missile-defense systems – without wanting to be too much of a conspiracy theorist, maybe what they actually want to do is make sure none of the information on board the satellite gets into the wrong hands???

Regardless of that issue, the fact remains that if this was to land in a populated area, it could cause numerous health problems, so I think the only safe thing to do is to shoot it down.

I take it we will never know exactly when they are going to shoot it down, what with national security and all that.

Richard
http://blogearth.wordpress.com/


Brandi Hammond   February 16th, 2008 5:13 am ET

I have a theory also. I read a week or so ago that this was coming down and the were NOT going to shoot it down due t all the risks with the gas. So why has that changed now? Or has it. Keep in mind people that this is the goverment that will not let the public in on much as to not caause chaos. I do not believe they intend to shoot it down, i think they are appeaseing the people like me that read it a week ago and spread the word that the S@# T was going to hit the fan.

also, on the news earlier this week , it was said (ONLY ONCE) that the sattelite was going to hit a very populated area.

So, i say to you all...do not panic...but be prepared
ie: survival kit, first aid kit, as we Houstonians know due to huricanes to keep that stuff around.

Just keep your eye on things

If there is a scientist out ther NOT working for the government, i would love to hear the projected areas that might be hit. I a thinking Cali, Texas, or Florida..

Anyone?????


US to shoot down dead spy satellite: Why? « exploring our world   February 17th, 2008 2:55 pm ET

[...] CNN has done an interesting analysis here. [...]


steve   February 19th, 2008 1:26 pm ET

I maybe wrong but isnt there a mutibillion dollar pickup truck up in space as we speak that could pick up the sattilite and bring it home safely
just curious


Ermengarde   February 20th, 2008 3:52 pm ET

CNN commentators are saying that shooting down ther spy satellite is like finding a needle in a haystack.

Whenever I'm looking for a needle in a haystiack, I use a magnet!


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