The CD-ROMs contain data from the JERS-1 Synthetic Aperture Radar (SAR) of the National Space Development Agency of Japan (NASDA). The data have been "mosaicked" into mosaic tiles; each of which consists of about 50 JERS-1 scenes.
The images are gray scale images in which the brightness of the image corresponds to the amount of radar energy reflected back to the radar.
There are five items on the CD-ROM desktops - a "DATA" folder, a "DOCS" folder, a "README.UNX" file (for UNIX computers), a "README.PC" file (for PC and Mac computers), and a "1STPAGE.HTM" file. (You may also see some other auxiliary files.)
The README is a short description of the CD-ROM in a text file, and "1STPAGE.HTM" is the first page of the html documentation. The "DATA" folder contains all the GIF images and binary data. The "DOCS" folder contains the html documentation.
The data are in two data formats : 1) 15 arcsec (445-465 meter) (pixel spacing) GIF images; 2) 3 arcsec (89-93 meter) (pixel spacing) raw 8 bit images. The pixel spacing (in meters) of each mosaic tile depends upon the Latitude and on the number of arcseconds per pixel for the tile. In general, the pixel spacing is close to 15 arcseconds (Latitude and Longitude) for the Lowres GIF images, and about 3 arcseconds for the raw 8 bit images.
The GIF images may be found either by clicking on the clickable map, or by clicking on an entry in the table of mosaic tiles.
You can find out if a location has been imaged, and, if so, which cd-rom it is on, using this web site.
The 8 bit raw images may be found in the "DATA" folder in the "BINARIES" subdirectory. These files will have the name ###.dat, where ### is the three digit tile number. The GIF images may also be found in the "DATA" folder in the "LOWRES" subdirectory.
You may request copies by visiting the GRFM home page (on the WWW), and clicking on the link for ordering instructions.
The best place to get more information is from ... GRFM home page (on the WWW).
These CD-ROMs were written, designed and produced by Bruce Chapman1, Al Wong1,Laura Hess5, and Ake Rosenqvist3 with assistance and contributions from Yasuaki Hashimoto4, Victor Taylor 2 , Masanobu Shimada2, Greg McGarragh5, and Tony Freeman1.
A portion of this work was carried out by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.
1Jet Propulsion Laboratory
2National Space Development Agency of Japan(NASDA)
3Joint Research Center - Space Applications Institute - MTV Unit (JRC/SAI)
4Remote Sensing Technology Center of Japan (RESTEC)
5University of California, Santa Barbara (UCSB)