Subject: BS: Oops! From: beardedbruce Date: 12 Feb 09 - 08:41 AM Russian, U.S. satellites collide in space Story Highlights Collision of two communications satellites believed to be the first of its kind NASA spokesman quoted as saying crash produced massive debris cloud Wreckage from collision expected to burn up in the Earth's atmosphere By Yuri Pushkin CNN MOSCOW, Russia (CNN) -- Two satellites, one Russian and one American, have collided some 800 kilometers (500 miles) above Siberia, the Russian federal space agency, Roscosmos, said Thursday. Debris from the collision poses no threat to the International Space Station. The collision produced two large debris clouds, which are not believed to pose a threat to the International Space Station as long as the clouds continue moving in a lower orbit, Roscosmos said. There is a chance the debris could hit other satellites at the same altitude, however, the space agency said. "We have not received a warning of the possible danger to the ISS. The fragments may descend to the ISS orbit in several years, although I do not rule out that some fragments may go down within several days," Mikhail Martirosov, from the Russian mission control center, told the Russian news agency Interfax Thursday. "The real threat will become obvious next week when we have enough information for calculating the trajectory of the fragments' descent," Martirosov said. "It will be weeks at least before the true magnitude of these clouds are known," RIA-Novosti quoted NASA spokesman Kelly Humphries as saying, adding analysts expect the wreckage from the collision to burn up in the Earth's atmosphere. The collision, which happened Tuesday, is believed to be the first between undamaged spacecrafts in orbit, Roscosmos said. The Russian satellite was launched in 1993 and is considered inoperative, news agency Itar-Tass and the Russia Today TV station reported. The U.S. satellite is part of the Iridium global mobile communications system and is owned by a consortium headed by Motorola, Russian media reported. It was launched in 1997. |
Subject: RE: BS: Oops! From: Rapparee Date: 12 Feb 09 - 08:46 AM Yeah, I saw that. Nobody seems to know how the debris field will affect other satellites, including the Hubble. The ISS seems not to be in danger. |
Subject: RE: BS: Oops! From: Nigel Parsons Date: 12 Feb 09 - 09:30 AM The second quote seems self-contradictory: The collision produced two large debris clouds, which are not believed to pose a threat to the International Space Station as long as the clouds continue moving in a lower orbit The fragments may descend to the ISS orbit in several years |
Subject: RE: BS: Oops! From: Rapparee Date: 12 Feb 09 - 09:36 AM Yes, and as long as they are in front of or behind the ISS the threat is slmall. As the orbits of the fragments decay they'll fall into lower and lower orbit, eventually burning up (or mostly) in the atmosphere. But this also demonstrates the feasibility of an anti-satellite weapon: simply explode a bunch of metal fragments in an orbit opposite to and in front of the satellite you want to take out. They'll punch it full of holes each time it passes through the fragment cloud. Not an original thought -- I first read it in, I think, the 1970s. |
Subject: RE: BS: Oops! From: Donuel Date: 12 Feb 09 - 10:57 AM Bigger than an opps. The odds are 10 trillion to one that the two craft seperated by 250 miles in altitude would collide. Historiclly 2 satillities have in fact been destroyed by weapon systems. One by China and one by the US. |
Subject: RE: BS: Oops! From: Nigel Parsons Date: 12 Feb 09 - 11:18 AM The odds are 10 trillion to one that the two craft seperated by 250 miles in altitude would collide. Actually, if they are separated by 250 miles they cannot collide. A collision requires zero separation! |
Subject: RE: BS: Oops! From: GUEST,beardedbruce Date: 12 Feb 09 - 11:36 AM (unless they have different eccentricities) it is possible for an orbit to intersect another, even when the radius is different. |
Subject: RE: BS: Oops! From: Rapparee Date: 12 Feb 09 - 12:55 PM Hey, my orbit is about as eccentric as they get. |
Subject: RE: BS: Oops! From: beardedbruce Date: 12 Feb 09 - 01:13 PM You as bad as IBEX? |
Subject: BS: Colliding Satellites From: OldPossum Date: 13 Feb 09 - 12:12 PM Here are some links concerning the event: |
Subject: BS: Russian-American Space Crash From: Ebbie Date: 13 Feb 09 - 04:49 PM They're saying that the debris from the crash could orbit the earth for thousands of years causing harm to potential entities for years to come because of the high speeds involved. Here My question: If everything were sent up to orbit in only one direction wouldn't that eliminate a good deal of the high velocity crashes? |
Subject: RE: BS: Russian-American Space Crash From: bubblyrat Date: 14 Feb 09 - 07:24 AM No,because as their orbits decayed,they would start to cross the paths of other satellites,which would then crash into them !Go try it on the motorway (any motorway!) for a demonstration ! |
Subject: RE: BS: Russian-American Space Crash From: Rapparee Date: 14 Feb 09 - 10:36 AM No, because things are in higher or lower orbit. As the orbits decay (the object in orbit "falls" closer to Earth, mostly due to the pull of gravity) its velocity will increase and its orbit intersect that of another object. Tie a weight to string, hold the string, and then whirl the weight in front of you -- as the string's length shortens the weight faster and in a smaller circle. Do this with one string/weight in each hand and you'll get an idea of the problem (as well as improving your coordination). Better, have a friend whirl the other one while facing you. |
Subject: RE: BS: Russian-American Space Crash From: EBarnacle Date: 14 Feb 09 - 11:12 AM This is sort of like the situation on the Isle of Man in the old days. There was one road around the Isle and only two cars. Not too long after the situation was created, they had a head on collision. |
Subject: RE: BS: Russian-American Space Crash From: Ebbie Date: 14 Feb 09 - 11:21 AM lol, EBarnacle. And I see that my reasoning is incomplete. Even at that, however, an object coming up behind a moving object has less force upon impact than the same objects moving toward each other. I will now shut up. I have already said more than I know. :) |
Subject: RE: BS: Oops! (Russian-American Space Crash) From: Q (Frank Staplin) Date: 14 Feb 09 - 02:55 PM I remember an old Startrek episode which involved a spacehulk and crew who made a living salvaging space junk. Can't remember any details of the program. It won't be long before one will become necessary. And a collector center from which to send the junk into space towards another (someone else's) galaxy. |
Subject: RE: BS: Oops! (Russian-American Space Crash) From: Green Man Date: 28 Jan 11 - 05:17 AM Its life, but not a WE know it! |
Subject: RE: BS: Oops! (Russian-American Space Crash) From: Ed T Date: 28 Jan 11 - 06:40 AM orbit obit |
Subject: RE: BS: Oops! (Russian-American Space Crash) From: Jack the Sailor Date: 22 Jun 11 - 01:29 PM In the late 70's when I was keeping up with such things, I read that there were several thousands of pieces of "space junk" in orbit as well as a growing number of satellites. I guess that if there are only two objects up there the odds of collision are small. (one in millions or more) But the odds of ANY two of several thousand colliding are probably fairly high. Maybe, in the course of the 60 years were have been putting things in orbit, on the order of less than 1 in 10. |
Subject: RE: BS: Oops! (Russian-American Space Crash) From: banjoman Date: 23 Jun 11 - 06:57 AM Is there also a lot of liquid and solid waste circling up there? I was once told that the russians, in the early days, just emptied waste products to reduce weight for landing. Could possibly explain the yellowish hue seen in the sky some evenings? How about the astronaught who stepped on some chewing gum? He got stuck in Orbit |
Subject: RE: BS: Oops! (Russian-American Space Crash) From: EBarnacle Date: 23 Jun 11 - 12:37 PM EB, wearing my statistician hat. Jack, The above should have read something like this: The probability of a collision increases as an increasing number of objects are placed in proximity to each other on slightly different orbits. Factors include the orbits, orbital decay, solar wind, microgravitic effects of the objects themselves, prior intersections and other factors which I have not yet considered. |
Subject: RE: BS: Oops! (Russian-American Space Crash) From: Jack the Sailor Date: 04 Jul 11 - 12:15 AM I'm not sure what you are saying there EB, but I don't think proximity is a factor, in orbits proximity is not nearly as significant or dangerous as intersecting orbits and with intersecting orbits proximity is very unlikely except for at the moment when the two objects are at the same place at the same time. All of those other factors are those which make it more or less likely that the orbits of objects will intersect. If two (or more) items are in orbit and in proximity, the likelihood and certainly the potential energy of a collision would be far less. |
Subject: RE: BS: Oops! (Russian-American Space Crash) From: Keith A of Hertford Date: 04 Jul 11 - 05:24 AM There was a near miss withh the ISS a couple of weeks ago. The crew got in their re-entry capsules until the danger passed. It came within a few hundred yard. |
Subject: RE: BS: Oops! (Russian-American Space Crash) From: Keith A of Hertford Date: 04 Jul 11 - 05:26 AM http://www.bbc.co.uk/news/science-environment-13949956 |
Subject: RE: BS: Oops! (Russian-American Space Crash) From: EBarnacle Date: 04 Jul 11 - 09:23 AM If they are in the same orbit and travelling at the same speed, the probability of collision is 0. If they are in intersecting orbits, their relative speed and mass determine the energy of any meeting. The point of my earlier post is that the more objects out there, the higher the probability of collision. |
Subject: RE: BS: Oops! (Russian-American Space Crash) From: Donuel Date: 04 Jul 11 - 12:01 PM Littering in Space is legal as far as I know. |
Subject: RE: BS: Oops! (Russian-American Space Crash) From: Jack the Sailor Date: 04 Jul 11 - 12:29 PM The point of my earlier post is that the more objects out there, the higher the probability of collision. That is my understanding as well. |