Total number of operating satellites: 1,381 (includes launches through 12/31/15)[1]
Wasn't aware that the +15,000 satellites (loosely defined) currently orbiting the Earth (according to SATCAT) are mostly junk...
But one other really interesting thing I found once in this data was that a huge percentage of all earth orbiting satellites are debris from China's Fengyun 1C sat, which they blew up into currently over 5000 pieces to test a missile [2]. I just think it's funny that China did this, and now we have to track every single piece indefinitely. :)
I don't think it's really indefinitely. Sun-synchronous orbits are usually 600-800km up, and atmospheric drag makes orbits at that altitude decay eventually. It'll probably take decades before it's gone, but it's not stuck up there forever.
Another big debris incident was the 2009 collision of an Iridium satellite and a dead Russian communications satellite:
When you think about the volumes involved, it's pretty amazingly bad luck that they managed to bump into each other. These were fairly low and the debris is deorbiting reasonably rapidly, so it's not as big of a deal.
no, they'll just turn it off, in the entire history of geostationary telecom satellites nobody has launched one with enough reserve delta-V/propellant to deorbit itself. To go from a 36,000 x 36,000 km circular orbit to a 36,000 x 250 km orbit (where the atmospheric drag would cause it to reenter) is a LOT of retrograde delta-v required). There's talk of requiring enough reserve propellant to boost to a new 'graveyard' orbit 1000 km beyond geostationary before turning off a satellite, but it's rarely implemented.
fun satellite thing: there's actually a LOT of old geostationary orbit telecom satellites which are still alive for command and control, and their transponders still work, but they're out of mainstream commercial service because they've long ago exhausted their station keeping propellant. So you need an earth station dish with two axis tracking motorized servos/gears/stepper motors to talk to them reliably.
Listening to GOES with a handheld radio (they couldn't fit the entire signal in one channel because it was so wideband) was so cool. I never figured out how to decode APT signals but so sad that with the goes satellites goes the amateur ability to get weather images directly from space :/
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[ 3.5 ms ] story [ 32.7 ms ] threadPresumably the date is for the East Coast of the US, so that's tomorrow.
[1]: http://cimss.ssec.wisc.edu/goes/blog/archives/21278
Total number of operating satellites: 1,381 (includes launches through 12/31/15)[1]
Wasn't aware that the +15,000 satellites (loosely defined) currently orbiting the Earth (according to SATCAT) are mostly junk...
But one other really interesting thing I found once in this data was that a huge percentage of all earth orbiting satellites are debris from China's Fengyun 1C sat, which they blew up into currently over 5000 pieces to test a missile [2]. I just think it's funny that China did this, and now we have to track every single piece indefinitely. :)
[1] http://www.ucsusa.org/nuclear-weapons/space-weapons/satellit... [2] https://en.wikipedia.org/wiki/Fengyun
Another big debris incident was the 2009 collision of an Iridium satellite and a dead Russian communications satellite:
https://en.wikipedia.org/wiki/2009_satellite_collision
When you think about the volumes involved, it's pretty amazingly bad luck that they managed to bump into each other. These were fairly low and the debris is deorbiting reasonably rapidly, so it's not as big of a deal.
https://www.google.com/search?client=ubuntu&channel=fs&q=inc...