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Frequently Asked Questions (FAQS);faqs.509 By the time you redesign to accommodate available hardware and re-modify the launch pads, you may as well have started from scratch with a clean sheet design. WHY DATA FROM SPACE MISSIONS ISN'T IMMEDIATELY AVAILABLE Investigators associated with NASA missions are allowed exclusive access for one year after the data is obtained in order to give them an opportunity to analyze the data and publish results without being "scooped" by people uninvolved in the mission. However, NASA frequently releases examples (in non-digital form, e.g. photos) to the public early in a mission. RISKS OF NUCLEAR (RTG) POWER SOURCES FOR SPACE PROBES There has been extensive discussion on this topic sparked by attempts to block the Galileo and Ulysses launches on grounds of the plutonium thermal sources being dangerous. Numerous studies claim that even in worst-case scenarios (shuttle explosion during launch, or accidental reentry at interplanetary velocities), the risks are extremely small. Two interesting data points are (1) The May 1968 loss of two SNAP 19B2 RTGs, which landed intact in the Pacific Ocean after a Nimbus B weather satellite failed to reach orbit. The fuel was recovered after 5 months with no release of plutonium. (2) In April 1970, the Apollo 13 lunar module reentered the atmosphere and its SNAP 27 RTG heat source, which was jettisoned, fell intact into the 20,000 feet deep Tonga Trench in the Pacific Ocean. The corrosion resistant materials of the RTG are expected to prevent release of the fuel for a period of time equal to 10 half-lives of the Pu-238 fuel or about 870 years [DOE 1980]. To make your own informed judgement, some references you may wish to pursue are: A good review of the technical facts and issues is given by Daniel Salisbury in "Radiation Risk and Planetary Exploration-- The RTG Controversy," *Planetary Report*, May-June 1987, pages 3-7. Another good article, which also reviews the events preceding Galileo's launch, "Showdown at Pad 39-B," by Robert G. Nichols, appeared in the November 1989 issue of *Ad Astra*. (Both magazines are published by pro-space organizations, the Planetary Society and the National Space Society respectively.) Gordon L Chipman, Jr., "Advanced Space Nuclear Systems" (AAS 82-261), in *Developing the Space Frontier*, edited by Albert Naumann and Grover Alexander, Univelt, 1983, p. 193-213. "Hazards from Plutonium Toxicity", by Bernard L. Cohen, Health Physics, Vol 32 (may) 1977, page 359-379. NUS Corporation, Safety Status Report for the Ulysses Mission: Risk Analysis (Book 1). Document number is NUS 5235; there is no GPO #; published Jan 31, 1990. NASA Office of Space Science and Applications, *Final Environmental Impact Statement for the Ulysses Mission (Tier 2)*, (no serial number or GPO number, but probably available from NTIS or NASA) June 1990. [DOE 1980] U.S. Department of Energy, *Transuranic Elements in the Environment*, Wayne C. Hanson, editor; DOE Document No. DOE/TIC-22800; Government Printing Office, Washington, D.C., April 1980.) IMPACT OF THE SPACE SHUTTLE ON THE OZONE LAYER From time to time, claims are made that chemicals released from the Space Shuttle's Solid Rocket Boosters (SRBs) are responsible for a significant amount of damage to the ozone layer. Studies indicate that they in reality have only a minute impact, both in absolute terms and relative to other chemical sources. The remainder of this item is a response from the author of the quoted study, Charles Jackman. The atmospheric modelling study of the space shuttle effects on the stratosphere involved three independent theoretical groups, and was organized by Dr. Michael Prather, NASA/Goddard Institute for Space Studies. The three groups involved Michael Prather and Maria Garcia (NASA/GISS), Charlie Jackman and Anne Douglass (NASA/Goddard Space Flight Center), and Malcolm Ko and Dak Sze (Atmospheric and Environmental Research, Inc.). The effort was to look at the effects of the space shuttle and Titan rockets on the stratosphere. The following are the estimated sources of stratospheric chlorine: Industrial sources: 300,000,000 kilograms/year Natural sources: 75,000,000 kilograms/year Shuttle sources: 725,000 kilograms/year The shuttle source assumes 9 space shuttles and 6 Titan rockets are launched yearly. Thus the launches would add less than 0.25% to the total stratospheric chlorine sources. The effect on ozone is minimal: global yearly average total ozone would be decreased by 0.0065%. This is much less than total ozone variability associated with volcanic activity and solar flares. The influence of human-made chlorine products on ozone is computed by atmospheric model calculations to be a 1% decrease in globally averaged ozone between 1980 and 1990. The influence of the space shuttle and Titan rockets on the stratosphere is negligible. The launch schedule of the Space Shuttle and Titan rockets would need to be increased by over a factor of a hundred in order to have about the same effect on ozone as our increases in industrial halocarbons do at the present time. Theoretical results of this study have been published in _The Space Shuttle's Impact on the Stratosphere_, MJ Prather, MM Garcia, AR Douglass, CH Jackman, M.K.W. Ko and N.D. Sze, Journal of Geophysical Research, 95, 18583-18590, 1990. Charles Jackman, Atmospheric Chemistry and Dynamics Branch, Code 916, NASA/Goddard Space Flight Center, Greenbelt, MD 20771 Also see _Chemical Rockets and the Environment_, A McDonald, R Bennett, J Hinshaw, and M Barnes, Aerospace America, May 1991. HOW LONG CAN A HUMAN LIVE UNPROTECTED IN SPACE If you *don't* try to hold your breath, exposure to space for half a minute or so is unlikely to produce permanent injury. Holding your breath is likely to damage your lungs, something scuba divers have to watch out for when ascending, and you'll have eardrum trouble if your Eustachian tubes are badly plugged up, but theory predicts -- and animal experiments confirm -- that otherwise, exposure to vacuum causes no immediate injury. You do not explode. Your blood does not boil. You do not freeze. You do not instantly lose consciousness. Various minor problems (sunburn, possibly "the bends", certainly some [mild, reversible, painless] swelling of skin and underlying tissue) start after ten seconds or so. At some point you lose consciousness from lack of oxygen. Injuries accumulate. After perhaps one or two minutes, you're dying. The limits are not really known. References: _The Effect on the Chimpanzee of Rapid Decompression to a Near Vacuum_, Alfred G. Koestler ed., NASA CR-329 (Nov 1965). _Experimental Animal Decompression to a Near Vacuum Environment_, R.W. Bancroft, J.E. Dunn, eds, Report SAM-TR-65-48 (June 1965), USAF School of Aerospace Medicine, Brooks AFB, Texas. USING THE SHUTTLE BEYOND LOW EARTH ORBIT You can't use the shuttle orbiter for missions beyond low Earth orbit because it can't get there. It is big and heavy and does not carry enough fuel, even if you fill part of the cargo bay with tanks. Furthermore, it is not particularly sensible to do so, because much of that weight is things like wings, which are totally useless except in the immediate vicinity of the Earth. The shuttle orbiter is highly specialized for travel between Earth's surface and low orbit. Taking it higher is enormously costly and wasteful. A much better approach would be to use shuttle subsystems to build a specialized high-orbit spacecraft. [Yet another concise answer by Henry Spencer.] THE "FACE ON MARS" There really is a big rock on Mars that looks remarkably like a humanoid face. It appears in two different frames of Viking Orbiter imagery: 35A72 (much more facelike in appearance, and the one more often published, with the Sun 10 degrees above western horizon) and 70A13 (with the Sun 27 degrees from the west). Science writer Richard Hoagland has championed the idea that the Face is artificial, intended to resemble a human, and erected by an extraterrestrial civilization. Most other analysts concede that the resemblance is most likely accidental. Other Viking images show a smiley-faced crater and a lava flow resembling Kermit the Frog elsewhere on Mars. There exists a Mars Anomalies Research Society (sorry, don't know the address) to study the Face. The Mars Observer mission will carry an extremely high-resolution camera, and better images of the formation will hopefully settle this question in a few years. In the meantime, speculation about the Face is best carried on in the altnet group alt.alien.visitors, not sci.space or sci.astro. V. DiPeitro and G. Molenaar, *Unusual Martian Surface Features*, Mars Research, P.O. Box 284, Glen Dale, Maryland, USA, 1982. [Apparently the first lengthy consideration of the Face published. Does anybody know what it costs?] R.R. Pozos, *The Face of Mars*, Chicago Review Press, 1986. [Account of an interdisciplinary speculative conference Hoagland organized to investigate the Face] R.C. Hoagland, *The Monuments of Mars: A City on the Edge of Forever*, North Atlantic Books, Berkeley, California, USA, 1987. [Elaborate discussion of evidence and speculation that formations near the Face form a city] M.J. Carlotto, "Digital Imagery Analysis of Unusual Martian Surface Features," *Applied Optics*, 27, pp. 1926-1933, 1987. [Extracts three-dimensional model for the Face from the 2-D images] M.J. Carlotto & M.C. Stein, "A Method of Searching for Artificial Objects on Planetary Surfaces," *Journal of the British Interplanetary Society*, Vol. 43 no. 5 (May 1990), p.209-216. [Uses a fractal image analysis model to guess whether the Face is artificial] B. O'Leary, "Analysis of Images of the `Face' on Mars and Possible Intelligent Origin," *JBIS*, Vol. 43 no. 5 (May 1990), p. 203-208. [Lights Carlotto's model from the two angles and shows it's consistent; shows that the Face doesn't look facelike if observed from the surface] NEXT: FAQ #13/15 - Space activist/interest/research groups & space publications Xref: bloom-picayune.mit.edu sci.astro:28931 sci.space:51985 news.answers:4372 Path: bloom-picayune.mit.edu!enterpoop.mit.edu!eff!sol.ctr.columbia.edu!zaphod.mps.ohio-state.edu!wupost!darwin.sura.net!gatech!concert!borg!mahler!leech From: leech@mahler.cs.unc.edu (Jon Leech) Newsgroups: sci.astro,sci.space,news.answers Subject: Space FAQ 03/15 - Data Sources Keywords: Frequently Asked Questions Message-ID: <data_723318181@cs.unc.edu> Date: 2 Dec 92 17:43:06 GMT Expires: 6 Jan 93 17:43:01 GMT References: <diffs_723318039@cs.unc.edu> Sender: news@cs.unc.edu Followup-To: poster Organization: University of North Carolina, Chapel Hill Lines: 413 Approved: news-answers-request@MIT.Edu Supersedes: <data_720641635@cs.unc.edu> Archive-name: space/data Last-modified: $Date: 92/12/02 12:34:36 $ ONLINE AND OTHER SOURCES OF IMAGES, DATA, ETC. INTRODUCTION A wide variety of images, data, catalogs, information releases, and other material dealing with space and astronomy may be found on the net. A few sites offer direct dialup access or remote login access, while the remainder support some form of file transfer. Many sites are listed as providing 'anonymous FTP'. This refers to the File Transfer Protocol on the Internet. Sites not connected to the Internet cannot use FTP directly, but there are a few automated FTP servers which operates via email. Send mail containing only the word HELP to ftpmail@decwrl.dec.com or bitftp@pucc.princeton.edu, and the servers will send you instructions on how to make requests. The sources with the broadest selection of material are the NASA Ames SPACE archive and the National Space Science Data Center. Don't even ask for images to be posted to the net. The data volume is huge and nobody wants to spend the time on it. VIEWING IMAGES The possible combinations of image formats and machines is forebodingly large, and I won't attempt to cover common formats (GIF, etc.) here. To read PDS and VICAR (and many other) formats on Unix systems running X, use XV 2.11, available by anonymous FTP from export.lcs.mit.edu (18.24.0.12) in contrib/xv-2.11.tar.Z and the other standard X11 FTP sites. The FAQ for the Usenet group alt.binaries.pictures discusses image formats and how to get image viewing software. A copy of this document is available by anonymous FTP from the Usenet FAQ archives at pit-manager.mit.edu (18.72.1.58), in directory pub/usenet/alt.binaries.pictures. ONLINE ARCHIVES NASA AMES Extensive archives are maintained at NASA Ames and are available via anonymous FTP or an email server. These archives include many images and a wide variety of documents including this FAQ list, NASA press releases, shuttle launch advisories, and mission status reports. Please note that these are NOT maintained on an official basis. FTP users should connect to ames.arc.nasa.gov (128.102.18.3) and look in pub/SPACE. pub/SPACE/Index contains a listing of files available in the archive (the index is about 200K by itself). To access the archives by email, send a letter to archive-server@ames.arc.nasa.gov (or ames!archive-server). In the subject of your letter (or in the body), use commands like: send SPACE Index send SPACE SHUTTLE/ss01.23.91. The capitalization of the subdirectory names is important. All are in caps. Only text files are handled by the email server at present; use one of the FTP email servers described in the introduction to this section for images or programs. The Magellan Venus and Voyager Jupiter, Saturn, and Uranus CD-ROM image disks have been put online in the CDROM and CDROM2 directories. The disks will be rotated on a weekly basis. Thousands of images are available in these collections. The GIF directory contains images in GIF format. The VICAR directory contains Magellan images in VICAR format (these are also available in the GIF directory). A PC program capable of displaying these files is found in the IMDISP directory (see the item "VIEWING IMAGES" below). The NASA media guide describes the various NASA centers and how to contact their public affairs officers; this may be useful when pursuing specific information. It's in MISC/media.guide. Any problems with the archive server should be reported to Peter Yee (yee@ames.arc.nasa.gov). NASA SPACELINK SpaceLink is an online service located at Marshall Space Flight Center in Huntsville, Alabama. The system is specifically designed for teachers. The data base is arranged to provide easy access to current and historical information on NASA aeronautics, space research, and technology transfer information. Also included are suggested classroom activities that incorporate information on NASA projects to teach a number of scientific principles. Unlike bulletin board systems, NASA Spacelink does not provide for interaction between callers. However it does allow teachers and other callers to leave questions and comments for NASA which may be answered by regular mail. Messages are answered electronically, even to acknowledge requests which will be fulfilled by mail. Messages are generally handled the next working day except during missions when turnaround times increase. The mail system is closed- loop between the user and NASA. SpaceLink also offers downloadable shareware and public domain programs useful for science educators as well as space graphics and GIF images from NASA's planetary probes and the Hubble Telescope. You can dial in at (205)-895-0028 (300/1200/2400/9600(V.32) baud, 8 bits, no parity, 1 stop bit), or telnet to spacelink.msfc.nasa.gov (128.158.13.250, also known as xsl.msfc.nasa.gov) if you're on the Internet. Anonymous FTP capability will be offered in the future. Most of this information is also available from the Ames server in directory SPACELINK. NATIONAL SPACE SCIENCE DATA CENTER (NSSDC) The National Space Science Data Center is the official clearinghouse for NASA data. The data catalog (*not* the data itself) is available online. Internet users can telnet to nssdca.gsfc.nasa.gov (128.183.36.23) and log in as 'NODIS' (no password). You can also get the catalog by sending email to 'request@nssdc.gsfc.nasa.gov'. You can also dial in at (301)-286-9000 (300, 1200, or 2400 baud, 8 bits, no parity, one stop). At the "Enter Number:" prompt, enter MD and carriage return. When the system responds "Call Complete," enter a few more carriage returns to get the "Username:" and log in as 'NODIS' (no password). The system is menu-driven; topics available as of 4/10/92 are: 1 - Master Directory - NASA & Global Change 2 - Personnel Information Management System 3 - Nimbus-7 GRID TOMS Data 4 - Interplanetary Medium Data (OMNI) 5 - Request data and/or information from NSSDC 6 - Geophysical Models 7 - CANOPUS Newsletter 8 - International Ultraviolet Explorer Data Request 9 - CZCS Browse and Order Utility 10 - Astronomical Data Center (ADC) 11 - STEP Bulletin Board Service 12 - Standards and Technology Information System Data can be ordered from the NSSDC on CD-ROM and other formats. Among the many types of data available are Voyager, Magellan, and other planetary images, Earth observation data, and star catalogs. Viewers for Macintosh and IBM systems are also available. As an example of the cost, an 8 CD set of Voyager images is $75. Data may ordered online, by email, or by physical mail. The postal address is: National Space Science Data Center Request Coordination Office Goddard Space Flight Center Code 633 Greenbelt, MD 20771 Telephone: (301) 286-6695 Email address: request@nssdca.gsfc.nasa.gov NSSDCA is also an anonymous FTP site, but no comprehensive list of what's there is available at present. SPACE AND PLANETARY IMAGE FACILITY Available 24 hours a day via anonymous FTP from pioneer.unm.edu. Has approximately 150 CD-ROM's full of imagery, raw, and tabular data. To start, get the file: pioneer.unm.edu:pub/info/beginner-info This will hopefully give you all of the information you need to get data from their machine. beginner-info has been translated to other languages, you should look inside pub/info for the particular language that meets your needs. Contact help@pioneer.unm.edu. SPACE TELESCOPE SCIENCE INSTITUTE ELECTRONIC INFORMATION SERVICE stsci.edu (130.167.1.2) has a large amount of information about the Hubble Space Telescope available by anonymous FTP, such as status reports and newsletters, in addition to material oriented towards HST observers and proposers. Get the top level README file to begin with. Contact Pete Reppert (reppert@stsci.edu) or Chris O'Dea (odea@stsci.edu). ASTRONOMICAL DATABASES The full SAO stellar database is *NOT* available online, probably due to the 40 MB size. It may be ordered on magnetic tape from the NSSDC. A subset containing position and magnitude only is available by FTP (see "Astronomy Programs" below). nic.funet.fi (128.214.6.100) has a large collection of astronomical programs for many types of computers, databases of stars and deep sky objects, and general astronomy information in directory /pub/astro. This site is mainly for European users, but overseas connections are possible. mandarin.mit.edu (18.82.0.21) has the following data available via anonymous FTP in directory /astro: StarChart v3.2, orbital elements for bright comets and asteroids, the Yale Bright Star catalog, Saguaro Astronomy Club Deepsky and Double Star databases, some PC astronomy programs, and possibly more. Get astro/README. Contact ccount@athena.mit.edu with questions. The Ames archives contain a database of 8,436 galaxies including name, RA, declination, magnitude, and radial velocity in MISC/galaxy.dat. Supplied by Wayne Hayes (wayne@csri.utoronto.ca). iris1.ucis.dal.ca (129.173.18.107) has a number of GIFs from Voyager, Hubble, and other sources available by anonymous FTP in pub/gif (most of this data is also in SPACE/GIF on the Ames server). Please restrict access to 5pm - 8am Atlantic time. pomona.claremont.edu has the Yale Bright Star catalog for anonymous FTP in directory [.YALE_BSC]. Contact James Dishaw (jdishaw@hmcvax.claremont.edu). The Hubble Guide Star catalog is available on CD-ROM for the Mac and PC for $49.95 US (catalog # ST101). Astronomical Society of the Pacific 390 Ashton Ave. San Francisco, CA 94112 Phone: (415) 337-2624 9 AM - 3 PM Pacific Time FAX: (415) 337-5205 For German (and possibly other European) readers, Jost Jahn has a service to distribute astronomical data to interested amateurs at cost. About 30-40 catalogs are available for DM 6..8/disk. Several floppy disk formats are available. Because of the expense of receiving email on his system, he asks that you contact him by physical mail: Jost Jahn Neustaedter Strasse 11 W-3123 Bodenteich GERMANY Phone: FRG-5824-3197 ASTRONOMY PROGRAMS Various astronomy-related programs and databases posted to the net in the past are archived for anonymous FTP at multiple sites, including ftp.uu.net (137.39.1.9). Also see the ASTRO-FTP list posted to sci.astro monthly, which is more complete than this list. Astonomical/Space-related sources of interest in comp.sources.unix: Volume 8: phoon moon phase and date routines Volume 12,13: starchart starchart program & Yale Star data Volume 15: moontool shows moon phase picture on Suns Volume 16: sao reduced SAO catalog Astonomical/Space-related sources of interest in comp.sources.misc: Volume 8: moon another moon phase program Volume 11: starchart starchart program, version 3.2 Volume 11: n3emo-orbit orbit: track earth satellites Volume 12: starchart2 starchart program, update to version 3.2.1 Volume 13: jupmoons plotter for Jupiter's major moons [in perl] Volume 13: lunisolar lunisolar (not sure what this does) Volume 14: ephem-4.21 astronomical ephemeris, v4.21 Volume 14: n3emo-orbit patch to orbit 3.7 Volume 18: planet planet generation simulator Elwood Downey (e_downey@tasha.cca.cr.rockwell.com), the author of "ephem", has offered to mail copies to people who can't find it on one of the archives. XSAT, an X Window System based satellite tracking program, is available by anonymous FTP from export.lcs.mit.edu (18.24.0.12) in contrib/xsat1.0.tar.Z. Contact Dave Curry (davy@ecn.purdue.edu) for more information. Xsky, a computerized sky atlas for the X Window System, is available for anonymous FTP on arizona.edu in the directory [.SOFTWARE.UNIX.XSKY] as xsky.tarz. Contact Terry R. Friedrichsen (terry@venus.sunquest.com) for more information. The "Variable Stars Analysis Software Archive" is available via anonymous FTP from kauri.vuw.ac.nz (130.195.11.3) in directory pub/astrophys. This is intended for specialists in this field, and they would appreciate people from outside New Zealand confining their FTP access to the astrophys directory, as they pay a significant amount for Internet access. Contents are relatively sparse at present due to the youth of the archive - contributions are encouraged. Contact the archive administrator, Timothy Banks (bankst@kauri.vuw.ac.nz) for more information. The "IDL Astronomy Users Library" is available by anonymous FTP from idlastro.gsfc.nasa.gov (128.183.57.82). This is a central repository for general purpose astronomy procedures written in IDL, a commercial image processing, plotting, and programming language. Contact Wayne Landsman (landsman@stars.gsfc.nasa.gov) for more information. ORBITAL ELEMENT SETS The most recent orbital elements from the NASA Prediction Bulletins are carried on the Celestial BBS, (513)-427-0674. Documentation and tracking software are also available on this system. The Celestial BBS may be accessed 24 hours/day at 300, 1200, or 2400 baud using 8 data bits, 1 stop bit, no parity. Orbital element sets are available via anonymous FTP from the following sites: archive.afit.af.mil (129.92.1.66) NASA,TVRO,Shuttle directory: /pub/space ftp.funet.fi (128.214.6.100) NASA,TVRO,Molczan,CelBBS, directory: /pub/astro/pc/satel Shuttle (*) kilroy.jpl.nasa.gov (128.149.1.165) NASA,Molczan directory: /pub/space/ SPACE DIGEST ARCHIVES Copies of back issues of Space Digest are archived on LISTSERV@UGA.BITNET. Send mail containing the message "INDEX SPACE" to get an index of files; send it the message "GET filename filetype" to get a particular file. LANDSAT AND NASA PHOTOS You can get black-and-white 1:1M prints, negatives, or positives for $10, $18, $12 respectively for any Landsat data more than 2 years old from EDC, (Eros (Earth Resources Orbiting Satellite) Data Center). Call them at (605)-594-6511. You get 80 meter resolution from the MSS scanner, 135x180 kilometers on a picture 135x180 mm in size. I think you have to select one band from (green, red, near IR, second near IR), but I'm not sure. Digitial data is also available at higher prices. Transparencies of all NASA photos available to the public can be borrowed from the NASA photo archive; you can have copies or prints made. NASA Audio-Visual Facility 918 North Rengstorff Ave Mountain View, CA 94043 (415)-604-6270 PLANETARY MAPS The USGS address for maps of the planets is: U.S. Geological Survey, Distribution Branch, Box 25286, Federal Center, Bldg. 41 Denver, CO 80225 Maps cost $2.40 to $3.10 per sheet (a few come in sets of 2 or 3 sheets). The best global maps of Mars based on Viking images are 1:15,000,000 scale in 3 sheets. These maps are: I-1535 (2 sheets only) - relief, albedo, names I-1535 I-1618 (3 sheets) - relief, names I-2030 (3 sheets) - relief, topographic contours I-1802-A,B,C (3 sheets) - geology There are many other maps as well: 30 sheets at 1:5,000,000 scale in relief, albedo, geology, photomosaic forms (not all 30 sheets available in all formats); 140 sheets at 1:2,000,000 scale as photomosaics of the whole planet, about 100 sheets of interesting sites at 1:500,000 scale in photomosaic format, and lots of special sheets. Then there are maps of Mercury, Venus, the Moon, the four Galilean Satellites, six moons of Saturn and five of Uranus. [Phil Stooke (stooke@vaxr.sscl.uwo.ca), the author of this item, has offered to respond to email requests for information on any topic relating to lunar and planetary maps.] COMETARY ORBIT DATA The Central Bureau for Astronomical Telegrams and the Minor Planet Center announce the sixth edition of the Catalogue of Cometary Orbits in IAU Circular 4935. The catalogue contains 1292 entries which represent all known comets through November 1989 and is 96 pages long. Non-subscribers to the Circulars may purchase the catalogue for $15.00 while the cost to subscribers is $7.50. The basic catalogue in ASCII along with a program to extract specific orbits and calculate ephemerides is available on MS-DOS 5.25-inch 2S2D diskette at a cost of $75.00 (the program requires an 8087 math coprocessor). The catalogue alone is also available by e-mail for $37.50 or on magnetic tape for $300.00.