A commercial satellite owned by a U.S. company was destroyed in a collision with a defunct Russian military satellite in what NASA said was the first such accident in orbit, raising new concerns about the dangers of space debris.
The crash, which happened Tuesday in low-earth orbit, involved one of the satellites owned by closely held Iridium Satellite LLC and a crippled Russian military satellite that apparently stopped functioning years ago, according to U.S. government and satellite-industry officials.
The collision created two large clouds of debris floating roughly 480 miles above Siberia, and prompted space scientists and engineers to assess the likelihood of further collisions.
So much for “see and avoid.”
The real worry is the debris cloud. Ingesting FOD anywhere in your satellite structure at a relative speed greater than 5 miles per second will definitely ruin your day.
One of these days, someone is going to make a killing cleaning up the LEO space….
I can only see more of this to come, what with the Russkies and now the ChiComms throwing junk up there and failing to maintain it.
480 ain’t LEO, maybe 100 miles is LEO. Owhell, depending on Solar weather etc. the pieces may bump into enough ionized air atoms to come down, after a while. I remember helping to shoot holes in a simulated Skylab meteor curtain with a light gas gun, back in the early seventies. A few little glass beads can make a nice crater at that speed. I think 5 km/sec was the best we could do.
P.s. I wonder if one could hop up his air rifle by using helium as the working fluid, instead of air.
I wonder what the relative inclination of the two orbits was. I am thinking it was significant – like the Russian was in a polar orbit and the Iridium was significantly more equatorial. This would give a greater relative velocity and more energy to the collision. I think our spy satellites tend to use polar orbits but I don’t know about Iridium. Two satellites with similar orbits wouldn’t smack together so hard. When they’re very similar it’s a rendevous!
A highly eccentric orbit (non circular) might generate a higher enery collision if it intersected a circular orbit at the right time, but I wouldn’t think either satellite would benefit from eccentric orbits. For spy work or comm you would want a pretty constant distance from the surface.
Iridium uses a polar orbit
Iridium – 86.39 deg
Cosmos – 74.03 deg
Just a “glancing blow” in orbital terms.
George, the Russkis are so far north, they have to use high-inclination orbits whether they like it or not. Molniya’s were Sun-synchronous in a way, I believe.
I do fondly remember getting up on the roof of the house here with my kitteh, a few years back, and watching an AF shuttle launch into polar orbit at night. Watched the glowing smoke of the solids, the separation, and then the little pinpoint glow of the SSMEs, all the way to brennschluss.
Best experience I’ve ever had in the Police-Republican Damnyankee Golftrash Paradise, aka Collier County, FL
Umm, Formerly, were they going in the same direction? You can launch Southerly, or Northerly.
How is it known that the Russian satellite was actually “defunct”?
Justthisguy,
Your comment about watching the shuttle launch brings back some memories. When I was a kid (early 60′s) we lived in Whittier, CA, in LA county. We could see launches going south from Vandenberg if they were after dusk when the sun lit the exhaust trail. We would also see the occasional launch failure – the rocket going off course followed by destruction.
That was in the grand days of the space program when every kid was sure there’d be space liners to Mars when we were adults. Good times it was…..
The raw inclination angles FkaS quoted are misleading (I almost made the same mistake, though). The collision angle was 102 degrees–just a bit in the head-on direction from broadside. Nice picture of the orbits at the time of the collision here.
This was just about the most difficult shot you could set up–a millisecond either direction and they would have missed.
They hit with a closing velocity of about 11.5 km/s–that is about 34 times the speed of sound at sea level.
While likely the first satellite-satellite collision, this isn’t the first time a satellite hit something. That honor goes to the French Cerise military satellite, which collided with a used rocket in 1996.
Lex,
I just don’t understand your answer. Which is it? Is the sky not big enough or is it the satellite not small enough? There was some kind of failure here. How do we fix this problem? What are we going to do?
Seriously, what scares me are the people who use this very same “Problem-Solving Strategy.” If you dare call that a strategy. Have they never heard of the “Blivot-Principle?” Hint: 10 pounds of BS in a 5 pound bag.
Grumpy
’twas only a matter of time. The Russian satellite was Cosmos 2251, a Strela 2-M communications satellite launched in a, yes, Molniya-type orbit in 1993.
Not the first collision but still one of the largest that, like the Chinese ASAT test (which also nailed a polar orbiter) generated a lot of debris in one of the worst possible orbital configurations. Lots of implications here – perhaps we may even see more like this (leaking reactor in defunct Soviet-era RORSAT).
The times just got a little more “interesting”…
- SJS
Grumpy:
How do you “fix it” ? You can’t – at least not with current technology. You work hard and track every little bit on orbit – which runs the gamut of aqctive and inactive satellites, errant tool bags, empty upper stages used to boost the satellites to orbit and debris from weapons tests. You track and predict conjunctions of these items and, if you can – if you have enough propellant (if you even have propellant) you ever so slightly adjust orbit so maybe you can miss. Maybe.
Ultimately, what goes up will come down, absent any controls to keep it on orbit. Some will come down sooner than others. Sputnik 1, the first into orbit, has long since burned its way back to earth. Our little grapefruit – Vanguard, that followed Explorer into space as our second US satellite, is still on orbit and will remain such for over 100 more years. Iran’s little Omid? Probably schedule a return party around une of next year.
And with all the junk on orbit, there are many things that can complicate matters. Consider – an upper stage that detonates instead of firing the way it is supposed to, adding a cloudof debris some of which is too small to track. four years later – a french COMSAT quits working, presumably after being struck by some of that debris that was too small to track.
Bottomline – just as seafaring nations must be more judicious in what is dumped overboard (no plastics) at sea, spacefaring nations need to be more circumspect about how they are placing assetts on orbit as well as what to do with decommissioned assets.
You know – just like Skylab and Mir, one day the ISS is going to come down too…
- SJS
SJS, I fully agree. This is the reason for the “Hint: 10 pounds of BS in a 5 pound bag.” The best term is a blivet, not blivot. Ah, the fine art of sarcasm.
SJS, have a great day and a great weekend.
As always,
Grumpy