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No, not really. How long has the Hubble space telescope been up there? Or is that outside the space junk zone? How many of our GPS satellites have been lost to collisions? How many of our TV satellites have been lost? Sure, there is a lot of space junk up there but without the statistics I can't make a call.
2 Satellites to date in 2009
The ISS and Hubble are equipped with ballistic shields.
The reason there are less collisions is due to active satellites maintaining their position with thrusters, but inoperable ones are collision hazards.
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Debris avoidance maneuvers with the shuttle can be planned and executed in a matter of hours. Such maneuvers with the space station require about 30 hours to plan and execute mainly due to the need to use the station’s Russian thrusters, or the propulsion systems on one of the docked Russian or European spacecraft.
At first glance it looks like two satellites crashed into each other but you say space junk caused the collision? How did it cause that collision?
I know one space shuttle hit a piece of paint that embedded itself into the wind shield.
Something that I wonder about, what direction is all this space junk moving in?
The Iridium satellite was operational at the time of the collision, the Russian satellite had been out of service since at least 1995 and was no longer actively controlled.
Kosmos-2251 was a 950-kilogram (2,094 lb) Strela military communications satellite. It was launched on a Kosmos-3M carrier rocket on June 16, 1993. It had been deactivated prior to the collision, and remained in orbit as space debris.
I would suspect that the space junk travels in the same direction of the satellites.
16). What can be done about orbital debris?
The most important action currently is to prevent the unnecessary creation of additional orbital debris. This can be done through prudent vehicle design and operations. Cleaning up the environment remains a technical and economic challenge.
NASA scientist Donald Kessler was brought back from retirement to work on managing the problem.
Kessler’s been warning about this issue since the late 70s, so much that the problem is called the Kessler Syndrome. It refers to the domino effect of all that debris crashing together.
I'm not denying the realityt of space junk but the intentionally destroyed satellite was not 'lost' and was not destroyed by an impact with space junk, so only one lost satellite (to space junk collisions). One too many of course. There have been quite a few lost satellites or rocket ships, including two space shuttles. How many didn't quite make it off the launch pad so to speak?
The thing that puzzles me is why satellites were not brought back to earth when they were at the end of their mission? It amazes me that they were simply abandoned and left out there.
Not snarky. Many people simply see large numbers and forget that they have to be placed in context.
The issue has to do with critical density not "critical mass".
Same thing in this case, since you are positing a classic example of nuclear reaction where one collision begets more collisions.
No it would not make sense to minimize space junk above the LEO. It's the space junk in the LEO that is problematic and has already resulted in two satellites crashing into each other in 2009.
LEO junk is only problematic short term (which may mean decades or more), since decay caused by friction from the outer reaches of the atmosphere will eventually clear it. Orbit debris ABOVE LEO wouldn't be washed away. It is a question of short term vs. long term priorities.
In 2007, China destroyed one of its own – an aging Fengyun-1C weather satellite – via an anti-satellite test. The satellite's destruction is now being viewed as the most prolific and severe fragmentation in the course of five decades of space operations. The result was littering Earth orbit with hundreds upon hundreds of various sizes of shrapnel.
Yep. (Of course if the U.S. had done it, it would be a "successful test of mass impactor technology. )
Most satellites, the International Space Station, the Space Shuttle, and the Hubble Space Telescope are all in Low Earth Orbit.
Yep. Cheaper and gets the job done.
High-altitude orbits are less commonly used than LEO.
But MUCH more important, since geosynchronous satellites allow so much communication data to be easily accessed with a fixed dish, etc. Although I love the idea of the ISS, it is really just a mobile home in space with some experiments that could just as easily be handled robotically, or at just about any orbital distance.
NASA spends almost $7 million a year tracking space junk.
Governmental agencies spending large amounts of money doesn't impress me. I had a brother who worked for NASA
How did the Chinese destroy their satellite? If it was blown up it would be interesting to know how the debris would behave. Much of it would be driven closer to earth in elliptical paths or maybe even into the atmosphere. Would any of it escape earth's gravity?
Not snarky. Many people simply see large numbers and forget that they have to be placed in context.
I was specifically referring to the very narrow LEO altitude around Earth not the entire vast Outer Space. Try and pay better attention to what people are talking about.
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Originally Posted by harry chickpea
Same thing in this case, since you are positing a classic example of nuclear reaction where one collision begets more collisions.
It’s not the same thing at all. Do you not know the difference between mass and density? Also critical density has nothing in common with a nuclear reaction. WOW just WOW!
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Originally Posted by harry chickpea
LEO junk is only problematic short term (which may mean decades or more), since decay caused by friction from the outer reaches of the atmosphere will eventually clear it. Orbit debris ABOVE LEO wouldn't be washed away. It is a question of short term vs. long term priorities.
Not completely accurate. LEO altitude is between 160-2000 kilometers.
Above 1,000 km, orbital debris will normally continue circling the Earth for a century or more.
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Originally Posted by harry chickpea
Does it make sense to minimize space junk above LEO, sure.
No it would not make sense to minimize space junk above the LEO, since most satellites, the International Space Station, the Space Shuttle, and the Hubble Space Telescope are all in Low Earth Orbit. It’s the LEO that has hit critical density not the space above LEO.
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Originally Posted by harry chickpea
Yep. Cheaper and gets the job done.
You missed the point Again it makes no sense to minimize space junk above LEO since high-altitude orbits are less commonly used than LEO.
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Originally Posted by harry chickpea
Yep. (Of course if the U.S. had done it, it would be a "successful test of mass impactor technology.
This is total rubbish.
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Originally Posted by Matadora…
NASA spends almost $7 million a year tracking space junk.
Quote:
Originally Posted by harry chickpea
Governmental agencies spending large amounts of money doesn't impress me. I had a brother who worked for NASA.
It was not meant to impress you. It demonstrates a huge waste of money. I also have a brother who worked at NASA in Houston...what does this have to do with the conversation?
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Originally Posted by harry chickpea
Again, you go back to the nuclear fission example.
No point in doing that since critical density has nothing to do with a nuclear fission reaction.
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Originally Posted by harry chickpea
Again, I suggest that at lower altitudes it will resolve itself through orbital decay.
This is not completely accurate.
The higher the altitude, the longer the orbital debris will typically remain in Earth orbit.
Debris left in orbits below 600 km normally fall back to Earth within several years.
At altitudes of 800 km, the time for orbital decay is often measured in decades.
Above 1,000 km, orbital debris will normally continue circling the Earth for a century or more.
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No need for snaky remarks. 
)
