PHOTO RELEASE NO.: STScI-PR94-21      Wednesday, May 18, 1994


             COMET P/SHOEMAKER-LEVY 9 "GANG OF FOUR" HST IMAGE

This is a composite HST image taken in visible light showing the
temporal evolution of the brightest region of comet P/Shoemaker-Levy
9.  In this false-color representation, different shades of red
color are used to display different intensities of light. 

[top panel]  - This shows data taken on 1 July 1993, prior to the
HST servicing mission.  The separation of the two brightest
fragments is only 0.3", so ground-based telescopes could not resolve
this pair. The other two fragments just to the right of the
closely-spaced pair are only barely detectable due to HST's
spherical aberration. 

[middle panel]  - This shows the first HST observation after the
successful servicing mission and was taken on 24 January 1994.  The
two brightest fragments are now about 1" apart, and the two fainter
fragments are much more clearly seen.  The light near the faintest
fragment is not as concentrated as the light from the others and is
elongated in the direction of the comet's tail.  

[bottom panel] - The latest HST observation, taken on 30 March
1994, shows that the faintest fragment has become a barely
discernible "puff."  Also, the second faintest fragment has clearly
split into two distinct fragments by March.  Continued splitting
events, such as those depicted here, will decrease the explosive
power of any single impact into Jupiter's atmosphere as the comet
makes its fiery plunge into this giant planet during the period
16-22 July 1994.  Fortunately, most of the fragments of P/S-L 9 have
apparently been stable for at least a year and have NOT shown any
evidence for further break-up. 

Credit:  Dr. Hal Weaver and T. Ed Smith (STScI), and NASA