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Landsat 7 Satellite Might Be Dead

Posted by timothy on from the pings-go-unanswered dept.

Lord Satri writes "Landsat 7 ETM+ remote sensing satellite, probably the most important Earth Observation satellite, might be dead now. This would have very important repercussions on the remote sensing / space community."

7 of 35 comments (clear)

  1. Software fix? by DustMagnet · · Score: 3, Interesting
    It looks to me like software fix would be possible, but the quality will be reduced. From this page it looks like a broken SLC would reduce the resolution of the image.

    The images must not look too bad, since it took them over a week to notice the problem.

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    'SBEMAIL!' is better than a goat!!
    1. Re:Software fix? by robslimo · · Score: 3, Informative

      Nope. The SLC physically modifies the imager's tracking, thereby modifying what is imaged. It keeps the imager from missing data in its desired, rectilinear image path.

      It is not a matter of diddling the image data to un-zig-zag it; without the SLC, the imager simply acquires the wrong data. Software *could* be utilized to interpolate and try to fill in the missing data at a lower resolution, but that would certainly leave a noticable zig-zag artifact of high-res diagonals filled between with lower res blurs.

      It's hardware, man. If we every get a shuttle back in the sky, maybe they can do a fly-by and have an astronaut give it a thump on the way by.

  2. I know who did it. by davidhan · · Score: 3, Funny

    It must have been that high school computer club new project! Damn meddling kids...

  3. "very important repercussions" ? by VisorGuy · · Score: 4, Informative

    "This would have very important repercussions on the remote sensing / space community."

    From the website
    "For current multispectral imagery, please be aware that Landsat 5 TM, EO-1 Advanced Land Imager (ALI), and ASTER may provide useful data alternatives."

    Doesn't sound like total gloom and doom to me; but what do I know, I'm no asstronomer...

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    This user account is inactive account replaced by the PDA
  4. Reports of its death have been greatly exaggerated by Buran · · Score: 3, Informative

    Note the phrase "The spacecraft itself appears to be in no danger..."

    Landsat 7 itself is still functioning. The Thematic Mapper is the instrument with the problem. These satellites contain other instruments on board which can be used to continue the mission.

    It's similar to how some of the instruments on board the Voyager spacecraft no longer function, but those that still work are returning useful data.

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    i am a soviet space shuttle
  5. Re:Reports of its death have been greatly exaggera by dmadole · · Score: 3, Informative

    These satellites contain other instruments on board which can be used to continue the mission.

    No it doesn't.

    As noted here and here and probably elsewhere, Landsat 7 contains only a single istrument -- the ETM (Enhanced Thematic Mapper).

    It's nothing like the Voyager spacecraft, which were multi-purpose and indeed contained many instruments. Landsat 7 was designed for exactly one specific function. If the ETM is badly broken, the whole satellite is pretty much a loss.

  6. Oh, yeah, suuuuure it's "dead" by stanwirth · · Score: 5, Insightful

    During the Reagan administration, when a high-resolution statellite instrument to measure the earth's geoid and topography was suddenly found to be extremely useful in locating submerged submarines (by way of their wakes) it, too, suddenly "went dead." I knew the guy at Lamont-Doherty Geophysical Lab who discovered how to recover the submarine wakes from these data. Funny how only the high-res instrument (the one that could detect submarine wakes) suddenly "went dead." The low-res instrument continued to return data. It was an open secret in the geophysical community that the high-res instrument didn't actually have a malfunction. Funny how the US won the cold war with a few years after that, too. Hrmmm.

    It was also the Reagan administration that privatised LandSat -- after spending billions of taxpayer's dollars to develop and deploy the LandSat satellites and do additional TM work from the space shuttle, suddenly all of the imagery was owned by a private company. And government-sponsored projects, instead of paying like $350.00 per scene, suddenly had to spend $3500.00 per scene. Double that to account for "University Overhead." What I want to know is, why, after paying for the development and deployment of this technology, do we (as taxpayers) then have to pay for it again when a project is formed to analyse these data? Didn't seem right at the time. Still doesn't seem right.

    But I honestly doubt the LandSat 7 TM instrument actually went dead. It was probably found to be returning data of military significance, and why bother with the political rigamarole with the scientific research community, not to mention the delay involved with classifying data -- when you can just claim the thing "went dead"? After all, who is going to make the trip to the thing itself to verify the claim that it "went dead"?