Shoemaker-Levy 9: Fragment K
The data, obtained between 10:23:10 and 10:25:37 UT July 19, 1994 (Earth receive time), shows the entry of fragment K, which looks like a bright flare on the dark side of Jupiter (directly visible from Galileo's perspective) between the terminator and the dark limb of the planet lasting approximately 35 seconds. The flare at its brightest is about 10% the total brightness of Jupiter (at this phase angle = 50 deg.)
The camera resolution is about 2500 km/pixel at the viewing distance of about 1.5 astronomical units. Possible additional phenomena are visible, but we cannot yet distinquish them clearly from cosmic ray hits; some features are Galilean satellites.
The data is not a series of snapshots of Jupiter. Rather, for purposes of increasing sensitivity and time-sampling, Jupiter was trailed in a directon roughly perpendicular to the line that connects the center of Jupiter with the impact site. The result is that Jupiter appears as a smeared (in one dimension) diagonal bar, with the limb to the right and the terminator to the left. This process was reset and repeated five times in each image frame. As a consequence time increases down the diagonal bars and to the right across the frame. K is the bright spot beyond the terminator; approximately 5.4 seconds separate the jailbar samples and 30 seconds separates each diagonal scan. The entire frame covers about 2.5 minutes of the K impact. The times given should be accurate to within +/- 2 seconds.
There are some not-so-obvious aspects of the scanning mode used for the K imaging data. There are short gaps in time between each of the diagonal swaths while the scan platform was repositioned. Visible horizontal jitter in the scan platform motion can be seen in the trails of the Galilean satellites and the K event; similar jitter in the direction parallel to the scans could affect the photometry of the event. Each CCD line across a Jupiter scan contains Jupiter's total flux.
