A wide variety of images, data, catalogs, information releases, and
    other material dealing with space and astronomy may be found on the net.
    The sources with the broadest selection of material are the NASA Ames
    SPACE archive and the National Space Science Data Center (described

    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' (or files referred to as 'FTPable'). 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 operate via email. Send mail containing only
    the word HELP to or,
    and the servers will send you instructions on how to make requests.

    Shorthand for a specific file or directory at an anonymous FTP site is
    sitename:filename (e.g. The FAQ
    is phasing out the specification of IP addresses and referring to FTP
    sites only by fully qualified machine name.

    An ever-increasing amount of space-related data may be searched and
    retrieved interactively using gopher, WAIS, World Wide Web, and other
    Internet clients that may be far more convenient than FTP. A description
    of these applications is beyond the scope of this FAQ; see the Usenet
    groups comp.infosystems.{gopher,wais,www} for more information.

    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.


    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 3.00, available by anonymous FTP from, as well as the other standard
    X11 FTP sites.

    The FAQ for the Usenet group discusses image
    formats and how to get image viewing software. A copy of this document
    is available from the Usenet FAQ archives in



    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.

    A listing of files available in the archive is FTPable from

    To access the archives by email, send a letter to (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/

    Any problems with the archive server should be reported to Peter Yee


    The ADS is a distributed data retrieval system which is easy to use and
    provides uniform access to ground-based and space-based astronomy data
    from NASA data centers across the country. It currently has over 140
    data catalogs of radio, infrared, optical, UV, and X-ray data which can
    be queried by position or any other parameter in the catalog. The ADS
    also provides tools to manipulate and plot tabular results. In addition,
    ADS has a Beta version of an Abstracts Service which allows users to
    query over 125,000 abstracts of astronomy papers since 1975 by authors,
    keywords, title words, or abstract text words.

    ADS use requires direct Internet access. For more info and to sign up to
    become a user, email The User's Guide and
    "QuickStart" Guide (PostScript files) are FTPable from directory

    Contact Carolyn Stern Grant (


    A WAIS database describing servers of interest to the space community is
    described by the source file:

           :version  3
           :ip-name ""
           :tcp-port 210
           :database-name "NASA-directory-of-servers"
           :cost 0.00
           :cost-unit :free
           :maintainer "";
           :description "Server created with WAIS release 8 b5.1 on May  5 14:05
1993 by warnock@Hypatia

    Maintainers of WAIS databases of interest to the NASA community can
    register their databases with the NASA-directory-of-servers by sending
    the source file to Contact Archie
    Warnock (

    NASA JET PROPULSION LAB (MISSION INFORMATION AND IMAGES) is an anonymous FTP site operated by the JPL Public
    Information Office, containing news releases, status reports, fact
    sheets, images, and other data on JPL missions. It may also be reached
    by modem at (818)-354-1333 (no parity, 8 data bits, 1 stop bit).

    Contact or phone (818)-354-7170.

    NASA LANGLEY (TECHNICAL REPORTS) is an anonymous FTP site offering technical
    reports. To get started, cd to directory pub/techreports/larc/92 and
    retrieve files README and abstracts.92. Most files are compressed
    PostScript. The reports are also in a WAIS database with the following

         :version 3
         :ip-name ""
         :tcp-port 210
         :database-name "nasa-larc-abs"
         :cost 0.00
         :cost-unit :free
         :maintainer "M.L.Nelson@LaRC.NASA.GOV";
         :description "NASA Langley Research Center Technical Reports



    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
    (, also known as if you're on the
    Internet. Anonymous FTP capability (password guest) is now available.

    Most of this information is also available from the Ames server in
    directory SPACELINK.


    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 ( and
    log in as 'NODIS' (no password). You can also get the catalog by sending
    email to ''.

    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

    The system is menu-driven; topics available as of 3/93 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
        13  -   Planetary Science & Magellan Project Information
        14  -   Other Online Data Services at NSSDC
        15  -   CD-ROMS Available at NSSDC

    For users with Internet access, datasets are made available via
    anonymous FTP once you select the desired datasets from the online
    catalog. For other users, data may be ordered on CD-ROM and in 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:


    STEIS contains a large amount of information about the Hubble Space
    Telescope, such as status reports and newsletters, in addition to
    material oriented towards HST observers and proposers. FTP to begin with. Contact Pete Reppert (
    or Chris O'Dea (


    The Space Telescope European Coordination Facility, at ESO/Garching
    provides on-line access to a huge astronomical database, featuring

        - Observation log files of several satellites/telescopes
        - Spectra and images (IUE, HST).
        - Most of the astronomical catalogues (SAO, HR, NGC, PPM, IRAS,
            Veron, GSC and many others, more than 50) in a very convenient
            way (give center+radius+kind of objects, and you get the
            corresponding files!).

    Log on as ``starcat'' (no password) on node
    ( or on STESIS (DECnet). The files created can be
    retreived by FTP. Contact: Benoit Pirenne, (phone +49
    89 320 06 433) at ST-ECF


    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). contains a large collection of astronomical
    programs for many types of computers, databases of stars and deep sky
    objects, and general astronomy information. This site is mainly for
    European users, but overseas connections are possible. is a database of 8,436
    galaxies including name, RA, declination, magnitude, and radial
    velocity, supplied by Wayne Hayes (* contains constellation
    boundary data in a form suitable for the construction of star charts and

    Directory has a number of GIFs from Voyager,
    Hubble, and other sources (most of this data is also in pub/SPACE/GIF on
    the Ames server). Please restrict access to 5pm - 8am Atlantic time.

    Directory[.YALE_BSC] contains the the Yale Bright
    Star catalog. Contact James Dishaw (

    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 mail 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. He also has
    a FAX service with current news on the observable sky. Email him if
    interested in these services, or write:

        Jost Jahn
        Neustaedter Strasse 11
        W-3123 Bodenteich
        Phone: FRG-5824-3197
        FAX: (49)-581-14824


    Various astronomy-related programs and databases posted to the net in
    the past are archived for anonymous FTP at multiple sites, including ( 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:      n3emo-orbit patch to orbit 3.7
    Volume 18:      planet      planet generation simulator

    Xephem is an interactive astronomical ephemeris program for X11R4/Motif
    1.1 (or later) X Windows systems. It computes lots of information about
    the planets and any solar system objects for which orbital elements are
    available. A sample database of some 16000+ objects is included in the
    release kit. It's available by anonymous FTP from and has been
    submitted to comp.sources.x. Contact Elwood Downey
    ( Ephem is the forefather of xephem
    designed for simple 24x80 character displays. It's FTPable from

    XSAT, an X Window System based satellite tracking program, is available
    from Contact Dave Curry
    ( for more information.

    Xsky 2.0.1, a computerized sky atlas for the X Window System, is
    available from[.software.unix.xsky]xsky2-0-1.tarz. Contact
    Terry R. Friedrichsen ( for more information.

    The "Variable Stars Analysis Software Archive" is available in directory 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
    ( for more information.

    The "IDL Astronomy Users Library" is FTPable from (to start with). This is a central
    repository for general purpose astronomy procedures written in IDL, a
    commercial image processing, plotting, and programming language. Contact
    Wayne Landsman ( for more information.


    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 FTPable from the following directories:   NASA,TVRO,Shuttle NASA,TVRO,Molczan,CelBBS,Shuttle   NASA,Molczan


    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.


    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

         NASA Audio-Visual Facility
         918 North Rengstorff Ave
         Mountain View, CA  94043


    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-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
    (, the author of this item, has offered to
    respond to email requests for information on any topic relating to lunar
    and planetary maps.]


    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

    Except for the printed version of the catalogue, the various magnetic
    media or e-mail forms of the catalogue do not specifically meantion
    non-subscribers. It is possible that these forms of the catalogue may
    not be available to non-subscribers or that their prices may be more
    expensive than those given. Mail requests for specific information and
    orders to:

        Central Bureau for Astronomical Telegrams
        Smithsonian Astrophysical Observatory
        Cambridge, MA 02138, USA

NEXT: FAQ #4/13 - Performing calculations and interpreting data formats