Both the STScI and the ST-ECF, as well as the CADC (see §3.1.3.) provide on-line information services and access to the complete HST Archive. The HST data archive is described in Pasian et al. (1993) and Long et al. (1994). As of mid-1994 the archive is comprised of some 2,000,000 files in 400,000 data sets and occupies 1.1 TB of storage space on optical disks, and new data continues to be archived at an average rate of 1.5 GB/day. Subject to proprietary period restrictions (typically one year) preview images of HST data are accessible through both the StarView user interface at STScI and through the STARCAT user interface at the ST-ECF and the CADC. The ``preview data'' are generated at the CADC and then sent to both the ST-ECF and STScI.
STScI runs a system called Space Telescope Electronic Information Service (STEIS), which is an anonymous FTP archive (also accessible via gopher and WWW) containing information on HST proposals, instruments, observation logs, and software. Of particular interest is the Archive Exposure Catalog (AEC), a list of all completed observations. Copies of the AEC reside in directory hst-archive in the files README.AEC, AEC.CATALOG, and AEC_SS.CATALOG, the latter containing solar system observations. A listserver (listserv@stsci.edu) supports many types of current awareness services, such as instrument news, weekly and daily summaries of performance, planned observing time-lines, and lists of completed observations. STScI's WWW home page is located at http://stsci.edu/top.html.
STScI has two host computers providing external access to the HST archive: stdata.stsci.edu (130.167.1.135, VMS operating system) and stdatu.stsci.edu (130.167.1.148, Unix operating system). To get started with the HST archives, telnet to one of these machines and login as user guest with password archive. Run the Starview user interface by entering the command starview (for the simple ASCII terminal version) or xstarview for the X Windows version. Note that you can also access the HST archive via STScI's WWW home page.
In order to actually retrieve data, the user must register (type register when logged in on stdata or stdatu, or register via the WWW archive page). Each user is given an individual account on either stdata or stdatu (user's choice). Data retrieved from the archive will appear in the data directory of stdata or stdatu. Users are sent e-mail when all requested data has been staged to these areas, and then the data can be transferred to your home machine using FTP. Use the command readnews to be kept up to date on the status of the archive and changes to the retrieval software.
Similar services are provided by the ST-ECF for European users of HST. The bulletin board service STINFO is accessed by telnet to stinfo.hq.eso.org with login username stinfo (no password). Questions about HST can be sent to an e-mail hotline stdesk@eso.org or ESO::STDESK. An anonymous FTP account, which includes a software library, various other software items, documentation, test images, and so on, is at address ecf.hq.eso.org. If you have WWW access, then the quickest on-line source of information regarding the the archive for HST and ESO data is available using the URL http://arch-http.hq.eso.org/ESO-ECF-Archive.html.
The ST-ECF also distributes HST data to European archival researchers. Data
requests are prepared from within STARCAT. While catalog browsing is
anonymous, a registration is necessary for retrieving data. The ST-ECF copy
of the HST archive is available via telnet to stesis.hq.eso.org; login as
user starcat, or contact catalog@eso.org for help. STARCAT also
provides an interface to a number of astronomical catalogs (listed in the
``Documentation for on-line catalogs'' item), including the capability of
sorting, selecting, and cross-correlating catalogs. On-line versions of the
``Star*s Family'' of directories, dictionaries, and data sets (see
§7.1. and §7.2.) are available from within STARCAT.
For further information and user's guides, contact B. Pirenne at the ST-ECF
(bpirenne@eso.org, ESO::BPIRENNE). For documentation on STARCAT
send a request to shill@eso.org.
Canadian users should request HST archive data through the CADC; contact cadc@dao.nrc.ca for more information.
[References: HST Catalog User Guide (1992); Schreier, Benvenuti, and Pasian (1991); Ochsenbein (1991); Pirenne et al. (1992); Adorf, Jackson, and Murtagh (1993); ST-ECF Newsletter (subscription requests to rfosbury@eso.org); STScI Newsletter (subscription requests to elliott@stsci.edu).]