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For Release: July 26, 1996

Photo No.: STScI-PRC96-25



HUBBLE'S 100,000TH EXPOSURE CAPTURES IMAGE OF DISTANT QUASAR


The Hubble Space Telescope achieved its 100,000th exposure June 22
with a snapshot of a quasar that is about 9 billion light-years
from Earth.

The Wide Field and Planetary Camera 2 clicked this image of the
quasar, the bright object in the center of the photo. The fainter
object just above it is an elliptical galaxy. Although the two
objects appear to be close to each other, they are actually separated
by about 2 billion light-years. Located about 7 billion light-years
away, the galaxy is almost directly in front of the quasar.

Astronomer Charles Steidel of the California Institute of Technology
in Pasadena, Calif., indirectly discovered the galaxy when he
examined the quasar's light, which contained information about
the galaxy's chemical composition. The reason, Steidel found, was
that the galaxy was absorbing the light at certain frequencies. The
astronomer is examining other background quasars to determine which
kinds of galaxies absorb light at the same frequencies.

Steidel also was somewhat surprised to discover that the galaxy is an
elliptical, rather than a spiral. Elliptical galaxies are generally
believed to contain very little gas. However, this elliptical has
a gaseous "halo" and contains no visible stars. Part of the halo is
directly in front of the quasar.

The bright object to the right of the quasar is a foreground star.
The quasar and star are separated by billions of light-years. The
quasar looks as bright as the star because it produces a tremendous
amount of light from a compact source. The "disturbed-looking"
double spiral galaxy above the quasar also is in the foreground.

Credit: Charles Steidel (California Institute of Technology, Pasadena, CA)
and NASA.


Image files in GIF and JPEG format and captions may be accessed on
Internet via anonymous ftp from ftp.stsci.edu in /pubinfo.

GIF JPEG
PRC96-25 HST's 100,000th Observation gif/100KObs.gif jpeg/100KObs.jpg

Higher resolution digital versions (300 dpi JPEG) of the release photographs
will be available temporarily in /pubinfo/hrtemp: 96-25.jpg (black/white).

GIF and JPEG images, captions and press release text are available via World
Wide Web at http://www.stsci.edu/pubinfo/PR/96/25.html and via links in:
http://www.stsci.edu/pubinfo/Latest.html or
http://www.stsci.edu/pubinfo/Pictures.html.