stolfi@jumbo.dec.com (Jorge Stolfi) (03/15/89)
Eric Harnden wriets: > > Fairly recently, some mention was made of interest in obtaining > data on star positions in a machine-readable format. I have > heard that NSSDC has just installed a CD-ROM pre-mastering > workstation. The first CD-ROM developed by them conatins 31 > astronomical source catalogs from the archives of the > Astronomical Data Center. I don't know if it is the same thing, but I just bought from NSSDC a CD-ROM with several astronomical catalogs, tables, maps and planetary images. The disk was produced by JPL and is called the Interactive Data Interchange (IDI) 1986 Science Sampler Disk. Apparently it is a grab-bag of files collected during a workshop whose primary goal was to test the feasibility of exchanging and collecting space data via computer networks. The files that made their way into the IDI disk are a quite mixed lot. Many of the files are random samples of larger data sets that hopefully one day will be published on their own. The data on the disk (some 600 Megabytes) includes, among other things * some star catalogs. * the IRAS (Infra-Red Astronomy Satellite) point source catalog. * a few radar and landsat(?) images of the Earth. * altitude maps (artificial images where brighter = higher) of the continental US, almost complete. * some images of the oceans (temperature and clorophyll concentration). * a table of planetary features (craters, mountains, etc) with names and locations. * miscellaneous Halley Watch observations for comet Crommelin. * some geological maps and miscellaneous data for Mars. * a dozen images of Phobos (Viking? Mariner?). * a couple hundred Voyager images of Jupiter, Saturn, and their satellites. So far I have only had time to browse through the Voyager images. Note that these are RAW images, with all the pixel defects, registration marks, missing scanlines, exposure errors, and so forth. They are *monochrome* images (taken through several filters, though), with 800x800 pixels at 8-bits per pixel. (That is about 650KBytes per image, so don't ask me to post them to the net!) Whether you will find them exciting or boring will depend on how interested you are in planetary exploration: their visual impact is is not great, but the resolution is the best you can get on this planet. Obviously, you need access to a computer with a greyscale display and a CD-ROM drive to make use of this disk. It won't play on a Videodisc player... Bundled with the CDROM comes a floppy disk with IMDISP, an Image Display Program written by JPL that runs on MS-DOS PC's with VGA/EGA/PGA/CGA cards. The package also includes a 60-page manual for IMDISP and the IDI CD-ROM. All this for $50 (Well worth it, IMHO). It seems that JPL is preparing a (multi-volume?) CD-ROM with all Voyager images taken during the Uranus encounter, which eventually will be available through NSSDC. The address to write to is Attn: Patricia Ross, Manager, Request Coordination National Space Science data Center (NSSDC) Central data Services Facility Goddard Space Flight Center Code 633.4 Greenbelt, Maryland 20771 Phone (301)286-6695 Enjoy Jorge Stolfi @ DEC Systems Research Center stolfi@src.dec.com, ...!decwrl!stolfi ------------------------------------------------------------------------ COMPACTDISCLAIMER: I am not a relative, employee, or stockholder of the U. S. Government. My only relation to JPL and the NSSDC is that of a satisfied armchair astronomer. Digital Equipment Corporation neither endorses nor disawows the opinions expressed herein; quite the opposite. Any errors or omissions in the above should be regarded as valuable contributions to the reader's life experience. Void where restricted or prohibited by law.