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Shuttle Radar Topography Mission Data

Posted by michael on from the land-navigation-made-easy dept.

SubtleNuance writes: "This story on Canada.com describes the mission and results of NASA's recent flight to map Earth. The Shuttle trip has provided the most detailed 3D photos of Earth ever released." Some of the images are just astounding. Too bad most of the data isn't available yet.

18 of 97 comments (clear)

  1. Contact your congresscritter by Zalgon+26+McGee · · Score: 4, Insightful
    Yet another reason to contact your congressman: ensure they vote for NASA appropriations.

    They aren't perfect, and more support for private enterprise in space is needed, but NASA is worthy of support.

    --

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    Book(n): Utensil used to pass time while waiting for the TV repairman

  2. Amazing! by ConsumedByTV · · Score: 2

    With maps like this you could do some very very real full scale simulations of war.

    Perhaps the brass might see that all war is futile.

    --


    "Not my manner of thinking but the manner of thinking of others has been the source of my unhappiness." - M
    1. Re:Amazing! by NullPointer · · Score: 2, Interesting

      With maps like this you could do some very very real full scale simulations of war.

      Actually, DOD did just that when US troops were sent to Bosnia. I was working on the commercial development of IFSAR at the time and got to see some of the results. The AirForce did some pretty cool virtual terrain demos for bomb-run training. Looks like TEC still has some images out there: http://www.tec.army.mil/ctis/ctis_tec/ifsare.html

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      NULL
  3. Resolution? by Sawbones · · Score: 2, Insightful

    Other than "The map is going to be 100-times better than any other global map that we have," in the article there is no mention of how fine of detail the map goes into. Is it better than the 1 meter resolution of the (now defunct *sigh*) Terraserver?

    Still, cool tech.

    --

    Ad in classifieds: Pandora's Box (no box) $5
    1. Re:Resolution? by NullPointer · · Score: 2, Informative

      Since Landsat (the image that is overlaid on the radar data) is typically 30m, these data sets won't be any better than that. If I recall, the shuttle X-band only did 100m DEM post spacing (or maybe it was 150m) with a vertical RMS in the 20m range, er, something like that.

      There are at least two commercial terrain mapping radar systems out there that can do much better. Star3i (formerly IFSARE) is now operated by Intermap (www.intermap.ca) and does 2.5m postings (Intermap may claim it does better, but I don't believe it). And, there is a new system that is currently being calibrated and may be producing data soon. In addition to X-band, GeoSAR has a P-band capability to "see" through trees, very cool (www.geosar.com).

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      NULL
    2. Re:Resolution? by Dancin_Santa · · Score: 2

      I don't think the Terraserver was able to return 3d surveys, though.

      Dancin Santa

    3. Re:Resolution? by leeward · · Score: 2, Insightful

      Terraserver, and other systems that produce resolutions on the order of 1 meter, are photographic systems. SRTM is an imaging radar system, with resolution of 20-30 meters. And the key part of the phrase in your quote is "better than any global map".

      The primary job of SRTM was to generate a uniform global topographic map. There are other radar systems, such as geosar, which can get better resolution. But that is because they are mounted on airplanes, and are therefore flying much closer to their target. But you are unlikely see a global map from geosar, or any other airborne radar, because, well, the earth is just too big to cover it all in an airplane. And just trying flying a US military imaging radar on an airplane over China! They get grumpy enough about the spy planes flying off their coast. And yet SRTM made a world wide map in a single 10 day mission (except somehow they missed Area 51 - don't know how that happened).

      And the value of a uniform map is that there are maps around from literally hundreds of data sources, but maps of two different areas, made with two different data sets, are difficult to compare accurately without a uniform baseline to compare them against. SRTM data is intended to be that baseline.

      And finally, an advantages of radar data over photographic data is that it is difficult to get accurate topographic data from optical data. Also, you are at the mercy of the weather when obtaining photo data. The radar can see through clouds just fine.

  4. Better link by DESADE · · Score: 4, Informative

    here

  5. Re:Resolution? just a note by onepoint · · Score: 2, Interesting

    on the page http://www.jpl.nasa.gov/srtm/datatimeline.html
    you'll see the resolution stats from 30m to 1 km

    and a side note
    http://www.jpl.nasa.gov/srtm/datacoverage.html Nasa states "Land area missed: 50,000 km2 (all in US)"

    ONEPOINT

    --
    if you see me, smile and say hello.
  6. Half empty glasses by Argy · · Score: 4, Interesting

    > Too bad most of the data isn't available yet.

    Is there a rule for Slashdot editors that their comments about good news have to be counter-balancingly negative?

    Considering that pilots and guided missiles may make life-and-death decisions based on this data, taking time to make sure it's accurate and properly processed seems like a good idea. If you have an urgent need, I suppose you could ask for 15,000 CDs of raw data, but all the crunched data should be available by the end of 2002.

    1. Re:Half empty glasses by Argy · · Score: 2

      I'm not particularly interested in the military function, but the article pointed out that "more than 160 military and intelligence systems will use the digital terrain-elevation data." Personally, I'm more apt to use it to chart elevation maps for trail marathons, but I doubt that's why the government shelled out the moola for this project. :-) I'm sure it will aid scientific research, as well as see some entertianment uses, but I doubt it would have been undertaken without a military purpose.

  7. Waaaaaiiiiiiittttttt........ by TheQuantumShift · · Score: 2, Funny

    NASA results on Canada.Com? Hmmmmmmmmmmm.........

    --

    Shift happens. Fire it up.
    1. Re:Waaaaaiiiiiiittttttt........ by Veritan+Drelor · · Score: 2, Interesting

      Speaking of NASA and Canada... A couple of years ago, NASA refused to launch a Canadian firm's imaging satellite specifically because it was more advanced than its American counterparts (no insult intended). As I recall, they negotiated with the Chinese to get the thing into orbit...... Oh, and on another note, resolutions better than 1 m are definitely out there. Whatever images have been released, I imagine an order of magnitude superior resolution has been achieved, but that the technology is kept secret.

  8. Hello, Joshua... by Rimbo · · Score: 2
    Perhaps the brass might see that all war is futile.

    Good evening Professor Falken
    A strange game
    It seems the only way to win is not to play
    How about a nice game of chess?

  9. They did better with Mars by alewando · · Score: 4, Offtopic

    It's odd that NASA is only now getting around to do with the Earth what they've been doing with Mars for years. (Follow that link for the pretty pictures, if nothing else.

    From 1998 to 1999, the Mars Global Surveyor made some 27 million topographical measurements of the red planet. With an average accuracy of 13 meters and sometimes as good as 2 meters. That's not much more than my height.

    Of course, having that precision on Earth would be more difficult with our thicker atmosphere and would raise profound privacy issues. On the other hand, government spy satellites probably routinely attain that precision without anyone's batting an eyelash. Maybe it's just as well that a civilian agency get in on the action too.

    1. Re:They did better with Mars by NullPointer · · Score: 2, Informative

      Actually, the original SRTM was flown back in 1994 (SIR-C and X-SAR) in an effort to update the military's DEMs. I never did hear what happened to that data (probably secret at the time). You can read a bit about it here:

      http://www.jpl.nasa.gov/srtm/spareparts.html

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      NULL
    2. Re:They did better with Mars by leeward · · Score: 3, Informative

      Umm... I designed and built some of the hardware for SIR-C (and also SRTM). There was absolutely no military connection to SIR-C. And X-SAR was built by the European space agencies, primarily the Italians on the antenna, and the Germans on the digital hardware, and they also had no military connection. The US military only got involved in SRTM after they saw how well the SIR-C radar worked, and after some of the SIR-C folks went looking for money to upgrade SIR-C to SRTM.

      SIR-C did not make topographic maps, except for one or two special tests using a technique called "repeat pass interferometry", because it did not have the outboard antenna on the 60M mast that SRTM had, and which gave SRTM its "stereo vision". And SIR-C only imaged a few small strips of the earth, each specifically requested by a scientist for some research purpose, or of course a few strips taken for PR purposes. SIR-C did not attempt to make a global map. This data is in the hands of the scientists involved, who supposedly continue to turn out papers based on the data. Also, SIR-C was conceived as a technology test experiment (and is also referred to as SRL - Space Radar Laboratory), used to test a variety of new radar technologies to see how well they worked from a spacebased platform.

  10. Re:Resolution? just a note by Wyatt+Earp · · Score: 2

    I think you are being paranoid, if those missed spots on the map are accurate.

    Looks like Northern Florida...west of King Harbor and Pensacola, central North/South Carolina, southern Minnesota/north Iowa, and the west Texas boarder area.

    Nothing fun there. South Central Utah, Colorado and Nevada are the sites that are suspected to be "sensative".