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FOR RELEASE: June 10, 1996

PHOTO NO.: STScI-PRC96-23a



SUPER-SHARP VIEW OF THE DOOMED STAR ETA CARINAE

A huge, billowing pair of gas and dust clouds are captured in this stunning
NASA Hubble Space Telescope image of the supermassive star Eta Carinae.

Using a combination of image processing techniques (dithering, subsampling and
deconvolution), astronomers created one of the highest resolution images of an
extended object ever produced by Hubble Space Telescope. The resulting
picture reveals astonishing detail.

Even though Eta Carinae is more than 8,000 light-years away, structures only
10 billion miles across (about the diameter of our solar system) can be
distinguished. Dust lanes, tiny condensations, and strange radial streaks all
appear with unprecedented clarity.

Eta Carinae was observed by Hubble in September 1995 with the Wide Field
Planetary Camera 2 (WFPC2). Images taken through red and near-ultraviolet
filters were subsequently combined to produce the color image shown. A
sequence of eight exposures was necessary to cover the object's huge dynamic
range: the outer ejecta blobs are 100,000 times fainter than the brilliant
central star.

Eta Carinae was the site of a giant outburst about 150 years ago, when it
became one of the brightest stars in the southern sky. Though the star
released as much visible light as a supernova explosion, it survived the
outburst. Somehow, the explosion produced two polar lobes and a large thin
equatorial disk, all moving outward at about 1.5 million miles per hour.

The new observation shows that excess violet light escapes along the
equatorial plane between the bipolar lobes. Apparently there is relatively
little dusty debris between the lobes down by the star; most of the blue light
is able to escape. The lobes, on the other hand, contain large amounts of dust
which preferentially absorb blue light, causing the lobes to appear reddish.

Estimated to be 100 times more massive than our Sun, Eta Carinae may be one of
the most massive stars in our Galaxy. It radiates about five million times
more power than our Sun. The star remains one of the great mysteries of
stellar astronomy, and the new Hubble images raise further puzzles.
Eventually, this star's outburst may provide unique clues to other, more
modest stellar bipolar explosions and to hydrodynamic flows from stars in
general.

Photo Credit: Jon Morse (University of Colorado), and NASA

Investigating Team: Kris Davidson (University of Minnesota), Bruce Balick
(University of Washington), Dennis Ebbets (Ball Aerospace), Adam Frank
(University of Minnesota), Fred Hamann (University of California - San Diego),
Roberta Humphreys (University of Minnesota), Sveneric Johansson (Lund
Observatory), Jon Morse (University of Colorado), Nolan Walborn (Space
Telescope Science Institute), Gerd Weigelt (Max Planck Inst. for Radio
Astronomy, Bonn), and Richard White (Space Telescope Science Institute)


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

GIF JPEG
PRC96-23a Eta Carinae color gif/EtaCarC.gif jpeg/EtaCarC.jpg

Higher resolution digital versions (300dpi JPEG) of the release photographs
will be available temporarily in /pubinfo/hrtemp: 96-23a.jpg (color),
96-23abw.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/96/23.html and via links in:
http://www.stsci.edu/pubinfo/latest.html or
http://www.stsci.edu/pubinfo/pictures.html.