ASTER Satellite Data and Silcast

The global ASTER DEM version 2 (GDEM2) is available

Silcast produces 15-meter DEMs (doing some oversampling) for individual images. Adjacent DEMs will not match perfectly.

As of April 1, 2016 , all ASTER scenes are free. (Nothing here has been verified since 2016.)

Go to NASA and request L1A Reconstructed Unprocessed Images. Enter the geographic range. Most people will want to specify daytime images. Click the Search button and wait 3-10 minutes for the list of matching images to appear. Make sure that your page is configured to show the cloud cover (not always accurate) for each quadrant of the image. If in doubt about coverage, open the browse image in another tab. Check the images you want and continue to the next page. Click on ordering options and select FTPpull. Files are available as hdf or geotiff. I have been downloading as hdf, as I have never tried geotiff as input to silcast.

Files will typically be available for download in several hours. The name of the file begins with LA1_003, followed by the date and time of image acquisition, following by the date and time of processing. There will be a binary .hdf file and an ascii .met metadata file.

We in ESS are fortunate in having a license to process these files in house. To process the raw files, you need

• silcast software. I have version 1.10 (There is a different numbering scheme for releases.) loaded on prism. (Version 2.00 is out, and we are considering the $310 upgrade.)
• the idl runtime library. I had trouble loading version 7.0, but 6.4 was easy and sufficient.
• the USB license dongle. See Harvey for this. There does not seem to be a way to make the dongle work under WIN7.

Tips for the old software

Files at the University of Washington Department of Earth and Space Sciences

• Gail's imagery:

  Gail Yamada compiled and indexed many scenes and DEMs before leaving the University. Harvey has explored the Tsangpo and Siang scenes, and incorporated them in the atlases used in the Tsangpo Expedition and the 2008 Siang expedition. Some work was also done with Carajas (ASTER_DEM20020717160053.hdf), SE Brasil and Hammersley.

• More scenes were acquired for the Siang.

  AST_L1A_00312182004042129_20080228200519_28393.hdf	sample atlas page
  AST_L1A_00312182004042137_20080228200519_28391.hdf
  AST_L1B_00311252007042137_20080212224245_29851.hdf
  AST_L1B_00311252007042145_20080212223945_28365.hdf
  AST_L1B_00311252007042154_20080212223945_28370.hdf
  AST_L1B_00311252007042203_20080212223945_28372.hdf
  AST_L1B_00312182007042801_20080212223925_28077.hdf
  AST_L1B_00312182007042809_20080212223925_28079.hdf
  AST_L1B_00312182007042818_20080212223915_27722.hdf
  AST_L1B_00312182007042827_20080212223915_27720.hdf

• Syria
• Olympics Mountains, for spectral anlysis of clearcut by Karen Hutten, NPS.
  • AST_L1A_00305082007191258_20080411001719_8492.hdf
  • AST_L1A_00305082007191307_20080411001659_8203.hdf
  • AST_L1A_00307252007192526_20080411001659_8207.hdf
  • AST_L1A_00307252007192535_20080411001709_8387.hdf
  • AST_L1A_00308252006191239_20080411001659_8220.hdf
  • AST_L1A_00308252006191248_20080411001719_8497.hdf
  • AST_L1A_00309012006191848_20080411001709_8385.hdf
  • AST_L1A_00309012006191857_20080411001719_8500.hdf
  • AST_L1A_00310132007192520_20080411001659_8213.hdf
  • AST_L1A_00310132007192529_20080411001659_8217.hdf
• Devon Island (for Sanjoy Som)

  AST_L1A_00304272003190446_20081216231255_1456.hdf
  AST_L1A_00304272003190455_20081216231255_1461.hdf
  AST_L1A_00305052007183409_20081216231255_1451.hdf
  AST_L1A_00305272005185753_20081216231255_1463.hdf

• Tierra del Fuego, for use with SAR ice-velocity maps.

  AST_L1A_00302132004142036_20081121221028_16349.hdf
  AST_L1A_00302132004142045_20081121221018_16288.hdf
  AST_L1A_00302132004142054_20081121221018_16293.hdf
  AST_L1A_00302242008141956_20081121221018_16296.hdf
  AST_L1A_00302242008142005_20081121221028_16356.hdf
  AST_L1A_00302242008142014_20081121221028_16353.hdf

• Parts of Antarctic Peninsula, for use with SAR ice-velocity maps.
• Central Chile for Phillippe Ruprecht's volcano studies
• Matanuska (Alaska) scenes for the basis of "Late Quarternary Megafloods from Glacial Lake Atna, Southcentral Alaska, U.S.A.", submission #129017 to Science

  AST_L1A_00303102002212017_20080419200353_11473.hdf
  AST_L1A_00306052005070846_20080419200343_11124.hdf
  AST_L1A_00306242000213400_20080419200403_11807.hdf
  AST_L1A_00306272002072321_20080419200343_11120.hdf
  AST_L1A_00307082003213657_20080419200343_11125.hdf
  AST_L1A_00307142005071525_20080419200343_11136.hdf
  AST_L1A_00307142005071534_20080419200353_11483.hdf
  AST_L1A_00308092005211749_20080419200353_11475.hdf
  AST_L1A_00304272006213646_20080520141942_22183.hdf
  AST_L1A_00305052002070515_20080520141942_22188.hdf
  AST_L1A_00305052002070524_20080520141942_22185.hdf
  AST_L1A_00305182002213849_20080520141932_21919.hdf
  AST_L1A_00305182002213858_20080520141942_22179.hdf
  AST_L1A_00307082003213648_20080520141922_21614.hdf
  AST_L1A_00307082003213657_20080520141932_21912.hdf
  AST_L1A_00305182002213832_20080519085945_10223.hdf
  AST_L1A_00305182002213841_20080519085946_10234.hdf
  AST_L1A_00307082003213630_20080519085935_8198.hdf
  AST_L1A_00307082003213639_20080519085935_8192.hdf
  AST_L1A_00301142006212927_20080331042347_6213.hdf
  AST_L1A_00301142006212927_20080411060645_2737.hdf
  AST_L1A_00301142006212936_20080411060635_2689.hdf
  AST_L1A_00301142006212945_20080411060615_2589.hdf
  AST_L1A_00301142006212953_20080411060645_2740.hdf
  AST_L1A_00302082006212326_20080411060655_2860.hdf
  AST_L1A_00302272007212526_20080411060635_2686.hdf
  AST_L1A_00304082006210550_20080411100731_26620.hdf
  AST_L1A_00304082006210559_20080411060655_2863.hdf
  AST_L1A_00305082006211811_20080411100731_26623.hdf
  AST_L1A_00305082006211820_20080411060705_2909.hdf
  AST_L1A_00305082006211828_20080411060705_2912.hdf
  AST_L1A_00305222006213035_20080411060715_2957.hdf
  AST_L1A_00305242006211812_20080411060625_2637.hdf
  AST_L1A_00306152006071508_20080411060625_2640.hdf
  and more

• Scenes of Mount Redoubt.
  • AST_L1A_00302142009213831_20090504143657_30675.hdf
  • AST_L1A_00302142009213840_20090504143647_30636.hdf
  • AST_L1A_00302142009213849_20090504143647_30634.hdf
  • AST_L1A_00303022009213832_20090504143637_30565.hdf
  • AST_L1A_00303022009213841_20090504143657_30682.hdf
  • AST_L1A_00304102009214440_20090504143637_30577.hdf
  • AST_L1A_00304102009214449_20090504143637_30575.hdf
  • AST_L1A_00304102009214458_20090504143637_30570.hdf
  • AST_L1A_00311012008214355_20090504143657_30680.hdf
  • AST_L1A_00311012008214403_20090504143637_30560.hdf
  • AST_L1A_00312032008214408_20090504143647_30619.hdf
  • AST_L1A_00312032008214417_20090504143647_30628.hdf
  • AST_L1A_00312032008214426_20090504143647_30624.hdf
  • AST_L1A_00301102009074051_20090505180531_23130.hdf
  • AST_L1A_00301102009074100_20090505180531_23124.hdf
  • AST_L1A_00301192009073451_20090505180531_23135.hdf
  • AST_L1A_00301262009074055_20090505180531_23137.hdf
  • AST_L1A_00302022009074707_20090505180541_23176.hdf
  • AST_L1A_00302112009074056_20090505180521_23065.hdf
  • AST_L1A_00302272009074056_20090505180521_23073.hdf
  • AST_L1A_00309042008074023_20090505180521_23076.hdf
  • AST_L1A_00310132008074628_20090505180521_23061.hdf
  • AST_L1A_00311142008074625_20090505180521_23078.hdf
  • AST_L1A_00312182008073439_20090505180531_23120.hdf
• Pack Forest, Washington. AST_L1A_00308142002191448_20090428205300_26310.hdf
• Scenes of Croatia for topographic and sprectral analysis of karst by Gabe Casale and Marijana Surkovic
  • AST_L1A_00301112004095252_20090325173638_26656.hdf
  • AST_L1A_00302022003094659_20090325173628_26491.hdf
  • AST_L1A_00302072005094504_20090325173628_26486.hdf
  • AST_L1A_00302122004095234_20090325173648_26713.hdf
  • AST_L1A_00303062004095833_20090325173648_26708.hdf
  • AST_L1A_00304152001100811_20090325173638_26661.hdf
  • AST_L1A_00305092003094556_20090325173638_26651.hdf
  • AST_L1A_00305092003094605_20090325173638_26646.hdf
  • AST_L1A_00305252003094604_20090325173628_26503.hdf
  • AST_L1A_00305252003094613_20090325173628_26501.hdf
  • AST_L1A_00306012003095214_20090325173628_26496.hdf
  • AST_L1A_00306242003095757_20090325173658_26763.hdf
  • AST_L1A_00306242003095806_20090325173658_26761.hdf
  • AST_L1A_00307102003095730_20090325173648_26720.hdf
  • AST_L1A_00307212004095119_20090325173638_26663.hdf
  • AST_L1A_00307212004095137_20090325173648_26702.hdf
  • AST_L1A_00309212003095127_20090325173648_26718.hdf
• Dry Valleys of Antarctica (including night and cloudy scenes)
  • AST_L1A_00302142003140849_20090522132644_5720.hdf
  • AST_L1A_00302162003135625_20090522132444_3648.hdf
  • AST_L1A_00302172003143922_20090522132654_5969.hdf
  • AST_L1A_00302202003150945_20090522132234_2770.hdf
  • AST_L1A_00302262003210311_20090522132644_5718.hdf
  • AST_L1A_00302262003210319_20090522132654_5971.hdf
  • AST_L1A_00312082002210353_20090522132654_5959.hdf
  • AST_L1A_00312082002210402_20090522132244_2808.hdf
  • AST_L1A_00312102002142128_20090522132644_5713.hdf
  • AST_L1A_00312282002203909_20090522132654_5954.hdf
  • AST_L1A_00312282002203918_20090522132704_6121.hdf
  • AST_L1A_00312292002145144_20090522132654_5963.hdf
  • AST_L1A_00312292002145144_20090522132704_6124.hdf
• Kuril Islands
  • AST_L1A_00305062003005941_20090616121346_28873.hdf
  • AST_L1A_00309052001010532_20090616121346_28856.hdf
  • AST_L1A_00309052001010541_20090616121346_28860.hdf
  • AST_L1A_00309052001010550_20090616121346_28865.hdf
  • AST_L1A_00309052001010559_20090616121346_28871.hdf
  • AST_L1A_00309132003004535_20090616121356_28911.hdf
  • AST_L1A_00309152007005248_20090616121336_28812.hdf
  • AST_L1A_00310152004005816_20090616121336_28811.hdf
  • AST_L1A_00310152004005825_20090616121336_28810.hdf
  • AST_L1A_00310172008010555_20090616121336_28816.hdf
  • AST_L1A_00310262008005914_20090616121336_28814.hdf
• Mount Everest AST_L1A_00310232003045929_20090616120515_27260.hdf
  Note to Adam I went ahead and imported the data because this is the first image that anyone ordered in both formats. This is interesting:
  a) Arcmap can read the HDF file directly. That gives you the 4100x4200 pixel VNIR data at sensor resolution, with an affine transformation to approximate lat-long space. If you zoom in, you see that pixels are tilted.
  b) The tiff files are that you ordered are the same size. They are displayed a few pixels out of register with HDF layer.
  c) When 3 tiff images are composited into a gridstack, they are 4934x4200 pixels as a tilted rectangle in a square edged with no-data cells.
  d) When 3 tiff images are composited into an img file, there are 4100x4200 pixels, and they are rectangular.
  e)When the HDF files are processed by silcast, they are projected to UTM and orthorectified. They are 4992 by 4776 pixels as a tilted rectangle within another rectangle. The image bands and the DEM cover a smaller area than the raw image. Only HDF files can be input to silcast.

Web Curator: Harvey Greenberg . . . . . about this site . . . . . What's New . . . .sorry