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ESA Satellite Recovers: Total Loss To Geostationary

Posted by timothy on from the falling-forward-all-the-time dept.

Slimbob writes "About 2 years ago an Ariane 5 rocket malfunctioned and left a very expensive Artemis satellite in an unusable orbit. Well, over the course of 18 months, the European Space Agency actually managed to push the satellite into a usable orbit using measly 15mN ion thrusters! They managed the feat by reprogramming about 20% of the original control software and uplinking the patches to the satellite! See the ESA press release . Achievements include the first first major reprogramming of a telecommunications satellite, the first orbital transfer to geostationary orbit using ion propulsion, and the longest ever operational drift orbit."

6 of 47 comments (clear)

  1. Fuel by GigsVT · · Score: 3, Interesting

    The article says they used up almost all the ion fuel, but yet it will still have enough for 10 years of trim thrusting, was the original planned life much longer, or did it just have that much extra fuel?

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    1. Re:Fuel by phobonetik · · Score: 2, Interesting

      I've been reading a few recent slashdot articles on Ion thrusters (e.g. the space ladder, I think). Where's a good intro on the things? I'm almost pleased they exist, sounds nice and sci-fi, even if i'm 21 :)

    2. Re:Fuel by warpSpeed · · Score: 3, Interesting
      The article says they used up almost all the ion fuel, but yet it will still have enough for 10 years of trim thrusting, was the original planned life much longer, or did it just have that much extra fuel?

      Since the operational drift is so much longer then what was originaly antisipated, I would be that they are consuming much less propellent then originaly expected, so they are able to get "10 years" out of what is left.

      GStar 3 or 4, put up by GTE in the late 80s, had a simmilar fate. It was lobbed into a bad orbit, written off (paid for), and then slowly (very slowly) moved into a "usable" orbit. The satellite had less propellent avaiable to it, so it was allowed to drift up and down, and side to side.

      GTE sold cheap time on the satellite since you could only get 5 to 20 minutes at a time without re-aiming your uplink antenna. A friend of mine wrote the software (in basic) that people used to aim thier uplinks antennas. However, since the satellite was paid for already, any money coming in was gravy at that point.

  2. Expect more ions in the future by TheSHAD0W · · Score: 4, Interesting

    The results of this botched lofting actually bode well for future satellite installations. Admittedly, using ion thrusters for final delivery would take much longer than using standard rocket technology, but it would also be enormously less expensive. The weight savings would be large, at a stage where weight is the most expensive part of the flight.

  3. On patching satellites by bill_mcgonigle · · Score: 2, Interesting

    Does anybody know what kind of authentication they use and how they deal with failed patches?

    Seems like somebody probably thought it through for the cost of one of these programs.

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    1. Re:On patching satellites by OneFix · · Score: 3, Interesting

      Just a wild guess, but it's probably similar to how the Tivo does its update procedure. There are 2 boot partitions on the system...when an upgrade comes through, the system tests the integrity of the upgrade, switches the boot partition and reboots...

      I would figure they probably use a more elaborate system...but it's probably the same in practice...of course, they have simulators/emulators on the ground that can accurately recreate the satelite's internal components...so, there should be no bugs in the system when the patches are sent...

      The only thing they'ld need to worry about is noise on the uplink (corrupted files) and possible hardware failure...corrupted files could be tested for prior to patching, and hardware problems can be fixed by having backup systems...