Hubble Images of Comet Hale-Bopp

96K
Observer: Hal Weaver
Location: Hubble Space Telescope
Date: October 23, 1995 06:30 UT

Above: Hubble Space Telescope (HST) images of comet Hale-Bopp taken at approximately 06:30 UTC on 23 October 1995 with the PC1 CCD chip of the Wide-Field Planetary Camera 2 (WFPC2). The upper left frame is a 60 sec exposure, the upper right is 300 sec long, and the lower frames are both 600 secs long. Each frame is 36.4 arcsec on a side, corresponding to 177,000 km at the comet. In all frames celestial North is at 130.7 deg CW from the straight up direction and East is at 90 deg CCW from North. (Sorry but these frames are rotated by approximately 180 deg from the September images. I'll rectify this during subsequent updates.)

These images have not been "cleaned", which means that they are littered with background stars (the comet is still near the galactic plane), cosmic ray events, and hot pixels. In the longer exposures the stars appear trailed since HST was tracking the comet.

The nucleus is near the center of the frame in the highly saturated region. This particular intensity stretch was chosen in order to bring out the faint feature that's about 3.5 arcsec due north the nucleus (i.e., at 131 deg CW from straight up). This feature is almost certainly the remnant of the outburst that took place on 10/13 and which was first reported during observations on 10/14 from the Teide Observatory in the Canary Islands. The average projected speed of this clump of material is about 20 meters/sec.

At the time of these observations it appears that the nucleus is in a quiescent state (i.e., not in outburst). While this makes for a less interesting coma (the above images are stretched like crazy in order to see anything), it should make it easier to put limits on the size of Hale-Bopp's nucleus.

Comet Hale-Bopp Home Page