Adaptive optics image of comet Hale-Bopp

The image shows innermost part of the comet's head. It is reproduced from an image that was obtained by Anne-Marie Lagrange, Jean Luc Beuzit and Patrice Bouchet on August 16-17, 1995, with the ADONIS adaptive optics instrument at the 3.6-metre telescope on La Silla. It is a composite of three 1-minute exposures through an infrared K-filtre centred at wavelength 2.2 microns. The field measures 13 x 13 arcseconds. The pixel size is 0.05 arcseconds. North is up and east is to the left. On this photo, the central condensation of the comet is clearly extended; it measures about 1.7 arcseconds across (FWHM), or about 7700 kilometres at the distance of the comet. It represents the densest part of the cloud of dust particles that surrounds the cometary nucleus. An asymmetric coma (dust cloud) extends towards the North.