Color SIR-C images

Description of images

Periodically during the course of the SIR-C mission (and after the mission), images have been "released" to the public (and given a P-number). These images are typically color images converted to GIF or TIFF format, and come in three sizes (thumbnail, browse, and full res). These images are not meant for scientific analysis, but they are interesting to look at, and generally illustrate the results of a science investigation.

Publicly released images only comprise a small fraction of the SIR-C dataset. Most SIR-C data is not publicly "released" (though the data is available). Only images that have been found to be "newsworthy" are publicly released (ie. as scientists use the data and discover something).

  • The "thumbnail" images are very small (about 10K bytes), and are meant to give an indication as to what is within the image.
  • The "browse" images are medium size (about a couple hundred K bytes), and are usually sufficient to determine the nature of the data. They are usually small enough that most web users can download them in a not unreasonable amount of time.
  • The "Full-Res" images are full resolution (pixel spacing is 12.5 to 25 meters), and are provided mainly to assist news organizations and magazines in making hard copy at good resolution. They are usually very large (sometimes larger than 10 Mbytes), and can take a long time to download. Overseas locations, and users with modem connections to the internet may find it difficult to download these images.

    The color images are formed by assigning various channels of the SIR-C data to one of the colors Red, Green, or Blue. Since SIR-C is an imaging radar, this is the only way to make a color image. The definition of each color varies slightly from image to image. This is the only SIR-C data or image product that is color (though you can make your own color images from the other SIR-C data products if you like).

    The publicly released images are often in an unusual coordinate system i.e. North might not be straight up. This is because the data were collected from the space shuttle which does not fly in a polar orbit.

    The caption associated with each publicly released image usually includes the following information : the center coordinates, the North direction, the radar channels that comprise the image, the date of observation, and a short description of the image.

    The images are not copyrighted, but we do request that if you use the images that you credit them to NASA/JPL.

    How do you get these images?

    These images can be copied directly off the web site. However, you can also order prints or slides of any of these images by contacting:

    Newell Colour
    221 North Westmoreland Avenue
    Los Angeles, CA 90064-4892
    tel. (213) 380-2980 ext. 269
    fax (213) 739-6984

    Tell the customer service representative the P-number (included at the end of the caption for each image) of the image and the type of product that you'd like.

    Three slide sets with some of these images are also available and can be ordered from:

    Finley-Holiday Film Corp.
    Box 619
    Whittier, CA 90601
    tel. (800) 345-6707
    fax (310) 693-4756

    SIR-C/X-SAR publicly released images

    "Full res" versions (listed by P number)