WWW Access to the HST Data Archive
Kirk Borne and Tim Kimball
borne@stsci.edu, kimball@stsci.edu
Space Telescope Science Institute
The Space Telescope Science Institute
(STScI) in Baltimore, Maryland provides the primary data archive facility
for Hubble Space Telescope (HST) data. Users of the
HST Data Archive
can browse the catalog of observations using our
StarView user interface,
which is accessible on the Internet by logging into one of our
two host computers
through a guest account.
In order to retrieve public data from the Archive,
users must register with us;
a registration form is available on the Web.
For users who would like to run the StarView windowing software
locally and only use the network to access the HST database, we provide
distributed versions
of the StarView software for SunOS and for VMS (Solaris and Alpha ports are
also planned). Binaries for Distributed StarView can be
downloaded via the Web at the push of a button.
Through our Web interface, we are able to provide several
on-line documents
and
conference papers
to assist researchers who are
planning to use the HST data. In addition, we provide instructions for new
users who are just
getting started
with the Archive.
Several
ASCII listings
of the Archive holdings are available via the Web. However, the StarView
user interface provides the most general access to the HST catalog
through a variety of search screens.
StarView also provides
a mechanism for
previewing spectra and images
prior to retrieving the archived
HST data. A prototype Web interface to the HST catalog is under development,
which will allow for simple catalog searches and for data previewing directly
via the WWW.
New developments within the Archive group at STScI include:
- Access to the VLA 20-cm sky survey images.
- WWW access to the HST Guide Star Digitized Sky Survey CD-ROM collection,
allowing users to extract arbitrary image sections of the digitized sky.
- On-line lists of the most recently released HST datasets, including
links to the proposal abstracts and to the preview data (images and spectra).
- Access to a wide collection of astronomical catalogs, with the capability
to cross-correlate their object lists with the contents of the HST Archive.
The HST Archive currently contains 368,300 distinct datasets, corresponding to
82,300 science observations. Of these, 36,700 are images and 30,900 are
spectra. In addition, there are 5,100 photometric observations and 9,600
astrometric observations available. The observed targets have covered all
categories of astronomical objects, of which 40% have been extragalactic, 50%
galactic, and 10% within the solar system. The entire volume of the HST Data
Archive system is currently 1.64 terabytes, and it is increasing at the rate of
roughly 2 gigabytes per day. Users are retrieving data from the archive at
nearly the same rate (2 Gbytes/day) through our StarView user interface.
In addition, there are currently about 3300 accesses to the
HST Data Archive Web pages
each week.
The HST Data Archive is becoming an increasingly active astronomical research
facility and the Web is providing greater and easier access to the data
holdings of the archive for researchers, educators, students, and the
astronomically interested general public.
Kirk Borne and Tim Kimball
Mar 28, 1995