Spatial distribution of molecules and dust within the coma of Comet Halley

Abstract

Spectral scans of comet Halley were made at high spatial resolution using the Cassegrain focus (f/13) of the 102 cm reflector at Kavalur (India). The scans cover the wavelength region from 3900 to 6200 A and at 40 A resolution and on a few occasions in the blue region at 20 A resolution. The f/13 beam provided an image of the coma with a scale of 15.5 arc sec/mm. Scans were obtained on several consecutive nights in Mar. 1986 with a 25.9 arcsec entrance aperture of the scanner at discrete and systematically displaced locations within the coma, in the direction of the tail as well as normal to it about the position of the nucleus. The spatial gradients of the distribution of the molecular species and dust were derived from the brightness profiles.