US spy satellite re-entry

Discussion in 'Astronomy, Exobiology, & Cosmology' started by blobrana, Jan 26, 2008.

  1. scotland Registered Member

    Possible launch location of spy sattilite in question..

    i still can't link so add the www

    and links to sum propaganda
  2. Google AdSense Guest Advertisement

    to hide all adverts.
  3. blobrana Registered Senior Member

    False Information Deleted (FID)
    Last edited: Jan 31, 2008
  4. Google AdSense Guest Advertisement

    to hide all adverts.
  5. blobrana Registered Senior Member

    forget what i said

    i plugged in the wrong data.... Yes the satellite was passing at 8:23 UT.

    congratulations you spotted the satellite.

    The two streamers? don't know it could be fuel
  6. Google AdSense Guest Advertisement

    to hide all adverts.
  7. blobrana Registered Senior Member

    Here is a predicted satellite position at 6:50 UT, Feb 1st, 2008.

    Please Register or Log in to view the hidden image!

    Expand (55kb, 630 x 390)

    Magnitude 4.8 v
    Orbit 273 x 271 km,
    inc 58.5 deg.

    (There is another chance to spot it at around 8:15 UT.)
  8. iceaura Valued Senior Member


    stupid question I can't answer for myself: In those pictures, what are the other two tracks - the ones that don't meet - representing?
  9. blobrana Registered Senior Member

    the `other two tracks` are just the same satellite track that is wrapped around the world.

    The satellite orbits in about 89 minutes; but for clarity the map just shows part of the ground track. The notches are spaced about a minute apart.
  10. Orleander OH JOY!!!! Valued Senior Member

    Anyone watch Dead Like Me? The satellite doesn't have a toilet on it does it?
  11. blobrana Registered Senior Member

    Probably not;
    Although the satellite is large every part of it would be reviewed before launch to cut down on weight.
    As the satellite is fully automated, the `essentials` such as toilets would be removed.
  12. Orleander OH JOY!!!! Valued Senior Member

    good, then I'm not worried

    Please Register or Log in to view the hidden image!

  13. Laika Space Bitch Registered Senior Member

    Out of curiosity, how big is a small armoured bus compared to, say, a small unarmoured bus?
  14. blobrana Registered Senior Member

    the same size;
    but it will be important as it starts to break up and burn up.

    (You remember what happened to the unarmoured asteroid that was heading straight for Springfield?)
  15. Orleander OH JOY!!!! Valued Senior Member

    so now they are gonna use missles and shoot it down??? Why??

    US Plans To Shoot Down Falling Military Spy Satellite

    WASHINGTON -- 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.

    The disabled satellite is expected to hit the Earth the first week of March. Officials said the Navy would likely shoot it down before then, using a special missile modified for the task.

    Other details about the missile and the targeting were not immediately available. But the decision involves several U.S. agencies, including the National Security Agency, the Department of Homeland Defense and the State Department.....
  16. Avatar smoking revolver Valued Senior Member

    Probably it's either dangerous to whomever that satellite is going to fall on the head, or there's some state secrets they don't want to fall (ha!) in the wrong hands.
    Either way it seems that not all of it is going to burn up.
  17. D H Some other guy Valued Senior Member

    The headline is a bit misleading in the sense that the military is not going to "shoot it down". They are simply going to shoot it. It will fall down all by itself.

    So why do this? They don't want the satellite to hit the ground. A largely intact sattelite might well do some damage if it lands in the wrong place. It could also do a lot of damage to the military if the pieces land in the wrong hands (i.e., people who can decipher the military secrets embodied in the satellite).

    Blowing the satellite up will do two things. First, it will blow it up (duh). The explosion itself may render unreadable the avionics and sensors that the military wants to keep out of enemy hands. Second, the fragments will burn up in the upper atmosphere. Big things (be it asteroids or satellites) have a much, much better chance of making it all the way to the ground than do little things. Aerodynamic friction is proportional to surface area and inversely proportional to mass.
  18. blobrana Registered Senior Member

    Blowing it up will create a lot of spacejunk; some of which will be shot up into higher orbits.
    As i remarked earlier, most of the parts that will survive the re-entry will not be affected by the explosion. The scatter field will just be made larger.
    As for sensitive `military secrets`; i feel that aspect is overrated.

    There real danger, it seems, is from the hydrazine onboard.
    The explosion will scatter the toxic propellant into the very upper atmosphere.

    Another perhaps political viewpoint, is that it will test the navy missile system...
  19. Echo3Romeo One man wolfpack Registered Senior Member

    The "space junk" aspect is irrelevant here. The satellite is in a rapidly decaying orbit and is already experiencing drag from the upper atmosphere. Component debris will fall in and burn up just like the bird would, only the fragments will have more surface area than the intact satellite, so they'll burn up faster. The chances of anything making it to earth will be greatly reduced, depending on how it breaks apart on intercept.

    Military secrets overrated? I'm going to take a wild guess that you've never held a security clearance.

    I'm not sure why the propellant should be a concern. There's not much of it, and there's a lot of room up there. What difference does it make?
  20. D H Some other guy Valued Senior Member

    Not too much higher. The vehicle is moving at 17,600 miles per hour. A few chunks might get an a boost of a few hundred mph. This will only change apogee; the perigee will remain unchanged. In other words, parts of the orbit will remain deep in the exoatmosphere. Those chunks will have a high surface area-to-mass ratio, so they won't survive as space junk for long.
    Debris from a reentering satellite does not always make it to the surface. A lot of it just burns up in the atmosphere. When satellite debris does hit the Earth, it is usually because the satellite didn't break up until it had plunged through a large part of the atmosphere. If the breakup occurs in the dense part of the atmosphere, the resulting debris will quickly slow down without overheating. If the breakup occurs high in the atmosphere there is a much smaller chance of debris reaching the Earth. The greatest heating occurs in the upper atmosphere where the atmosphere is still very thin and the vehicle (or its parts) still have near orbital velocity. This satellite will break up even higher than that, before entry interface.
    You don't know what capabilities this satellite has onboard. Hint: They're secret, probably TS. Learning by means of reverse engineering is fast, cheap, and effective. Destroying the satellite eliminates that learning tool.

    Where it will burn up.

    Edited to add
    A lot of the hydrazine will burn with the explosion. Hydrazine is a monopropellant (and a bipropellant as well; one of very few in this category). It does not take much energy to set hydrazine off. Contact with platinum will do it, and so will a boost of energy from an explosion.

    Bingo. This is a chance to use their fancy ASAT toys on a live target moving at 17,600 mph.
    Last edited: Feb 14, 2008
  21. Orleander OH JOY!!!! Valued Senior Member

    LMFAO!! You have got to be kidding me. :roflmao:

    Ah, hair splitters. <sigh>
  22. kmguru Staff Member

    IMHO, USA is itching to test their own version of the new fangled sattelite killers.

    1. Missile
    2. High energy Laser
    3. High energy particle gun

    Could be Northrup or one of the contractors want to sell something and this is a good way to test it before Uncle Sam will plunk down several Billion Dollars for the new system.
  23. draqon Banned Banned

    yes, this satellite will be destroyed by the USA missile...just like China destroyed one of their falling satellites not long ago

    Please Register or Log in to view the hidden image!

    by the way, the one Chinese have shot, the pieces of it are supposedly still in that high orbit and will remain there for hundred of years

    Please Register or Log in to view the hidden image!


Share This Page