Comet Hyakutake Outburst (April 15)

Observations from Pic du Midi

These two images of C/1996 B2 Hyakutake [GIF,152k] were taken under similar observing conditions at the Pic du Midi observatory in the French Pyrenees. A transitory outburst is clearly visible on April 15.85.

The filter was the RG 830 e=3 mm (Gunn 6). The scale was 222 km/pixel on April 15, and 252 km/pixel on April 18. The exposure duration was 60 seconds on April 15, and 110 seconds on April 18. North is up.

In order to remove the major part of the radial variation of luminosity in the coma, pixel values above sky background were enhanced according the empirical law 0.27*r^0.7 , were r is the distance to the nucleus in pixel units. No extra image processing was done.