Supply ships used to push ISS clear of sat-smash debris
2009 Russian wipeout of Iridium bird still causing snags
The International Space Station was given a shove by supply ships docked to it over the weekend in order to evade a cloud of high-velocity orbital shrapnel created when a Russian military satellite crashed into an Iridium comsat in 2009.
Aviation Week reports that astronauts and cosmonauts aboard the station fired three different thruster systems late on Friday night. Without this manoeuvre, according to US space tracking, debris generated by the collision above Siberia just over two years ago would have passed within 6.5 miles of the station.
The main shove for the shrapnel dodge came from the European Space Agency's ATV-2 robo supply capsule, docked at the station. The ISS' Russian service module also fired thrusters to provide pitch and yaw control during the burn, and roll control was provided by the thrusters of the Russian Progress supply capsule, also docked at the station.
The collision in 2009 saw Cosmos 2251 – a defunct military communications satellite launched in 1993 – crash into an up-and-running Iridium bird above northern Russia. The Iridium constellation was originally intended to be the world's first global mobile phone network, but as things turned out international GSM roaming beat it to the punch.
Iridium went bankrupt, but was then reborn with US government backing: it remains one of the few solutions offering truly worldwide voice and data (albeit very limited bandwidth) without requiring a cumbersome directional dish. As such it is often used in military and intelligence applications – for instance certain kinds of tracking bugs, communications with submerged submarines etc etc – perhaps offering a clue as to why the US authorities were keen to see it saved.
The 2009 collision was thought to result in only brief, local network outages for the Iridium system and full coverage was restored swiftly. The resulting wreckage pushed up overall space debris levels in near-Earth space by around 3 per cent. Initially the debris cloud was not dangerous to the ISS, but as time has gone by some of the fragments have descended to the same orbital level as the station.
Following the satellite crash, conspiracy theories circulated widely to the effect that Russia might have taken the Iridium satellite out on purpose – perhaps in order to prevent a particular satphone call/tracking bug report/submarine "page" etc from getting through.
Regardless of such considerations, debris is a growing threat to all space operations. At the moment most countries rely on the US military Space Surveillance Network to monitor the situation, but the ESA has aspirations towards a system of its own in future. ®
So if the US military system is so great, why was it that no-one stopped the Iridium satellite from crashing into a piece of space rubbish? Because that wasn't their job. Their job was to look for intercontinental balistic missiles with nuclear warheads flying towards America.
So therefore a system that is designed just to prevent this type of thing happening, and is not affraid to publish the data of everything up there so that people can work out and avoid possible collisions is a good idea.
Redundancy is another reason. Why does your car have 2 breaking circuits? What a waste! We should get rid of one of them for you. Similarly when you fly on a plane, we should remove all the redundancy there too; it's so wasteful having 2 things that might do the same job...
Galileo != GPS
Yeah they'll do the same job for your average glib comment tossing prat in the street but Galileo is designed such that it can be relied upon. Life is far to short to try explaining that concept to you. So yeah you're right, Galileo will do absolutely nothing to stop you driving your 4x4 up a railway line when your £49.99 sat nav tells you to so therefore it must be a complete waste.
Fine by me, but then I'm a US citizen.
The question for you is:
Do you really want to always be dependent on whatever wanker may be sitting in the Big House?
They can cut off your connection to that all important link in a New York second. Me, I'd want a back up under the control of my own government. Frankly I'd prefer one under my specific control, but I don't have that much money, so I settle for the next best option.