Midair in space!

steingar

steingar

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steingar
An Irridium communications satellite collided with an inactive Russian bird in low orbit. Story here.
 
"...sources report that neither satellite had filed a flight plan..." :D
 
steingar said:
An Irridium communications satellite collided with an inactive Russian bird in low orbit. Story here.
Click to expand...

I always thought that the Irridium sats had their own guidance and thrust system to position them in the proper orbit. Wonder why they just didn't move it prior to collision?

Anyway, space is propably a "no-fault" zone, most likely covered by Geico. :D

Gary
 
Did the have the new locator's (406's)... Otherwise, they may not be able to find themselves
 
So much for the "big sky" theory.

Bob Gardner
 
There's almost always insurance for the launch but it expires once the space craft is on orbit. I was involved once in putting Telstar IV up that didn't make it due to a booster malfunction. $75M down the toilet for Lloyds of London.
 
steingar said:
An Irridium communications satellite collided with an inactive Russian bird in low orbit. Story here.
Click to expand...

The story says they collided at 6 miles per second, which gives me 21,600 MPH. No wonder there was a "cloud of debris." They must have been on radically different tracks, since at the same altitude their orbital speeds would have been the same.

Dan
 
Dan Thomas said:
The story says they collided at 6 miles per second, which gives me 21,600 MPH. No wonder there was a "cloud of debris." They must have been on radically different tracks, since at the same altitude their orbital speeds would have been the same.

Dan
Click to expand...

well if they werent at the same altitude they wouldn't have collided. very easy to imagine they were at the same altitude in different orbits.
 
They track the space objects... the real question is, "did they know in advance" that there was a possibility of collision (and if so, how far in advance). I really hope this wasn't a total surprise... would make me nervous about being on the ISS if it was a total surprise!! :)
 
TangoWhiskey said:
They track the space objects... the real question is, "did they know in advance" that there was a possibility of collision (and if so, how far in advance). I really hope this wasn't a total surprise... would make me nervous about being on the ISS if it was a total surprise!! :)
Click to expand...
Yes space objects are tracked. All objects going into space are also tracked so as to ensure no collisions. The orbital elements are published every week. I subscribe to a bunch of them for being able to track communications satellites. The questions here are why did the prediction software not signal a conflict and who dropped the ball.

BTW I use SatPC32 for my tacking program. It is also hooked up to my sat transceiver and will make the Doppler shifts to the uplink and downlink frequencies. I still have not hooked the rotor controller to the PC yet. I still have to manually move the antennas.
 
Dan Thomas said:
The story says they collided at 6 miles per second, which gives me 21,600 MPH. No wonder there was a "cloud of debris." They must have been on radically different tracks, since at the same altitude their orbital speeds would have been the same.
Click to expand...

Depends on the eccentricies of the orbit. Perfectly possible for the satellites to have different velocities, if one was in a non-circular orbit. The Russians put some comsats into 12-hour orbits with apogees o ver 15,000 km and perigees down at 1000 km or so, though the apogees are over the northern hemisphere so this couldn't have been one of them.

It'd be interesting to see some of the final tracking, to determine if they "T-Boned" or "side-swiped."

Ron Wanttaja
 
smigaldi said:
Yes space objects are tracked. All objects going into space are also tracked so as to ensure no collisions. The orbital elements are published every week.
Click to expand...

Back when I was driving satellites, we got a warning from NORAD if an object was going to come close. But these were USAF satellites...I don't know if NORAD issues a warning as a matter of course.

It's possible that civilian users might actually have to pay for the service. NOT buying such warnings probably seemed a pretty good idea, up until yesterday. :smile:

One factor to consider is that the orbit propagation is not accurate enough to provide true collision warning for inert objects. Don't know what the accuracy is, but remember you'd have to have an accuracy in single-digit meters for a true collision warning. Otherwise, you might be jinking INTO the bogey....

Ron Wanttaja
 
stk.jpg


Orbital track animation available @ http://www.spaceweather.com/
 
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Yeah, the title is a bit of an oxymoron. But midair is a bit of a euphemism, so I'm not too embarrassed.
 
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