These images illustrate the changes taking place in the plasma tail of Comet Hale-Bopp after perihelion passage. They were taken by Eric W. Elst on 2, 4 et 6 April 1997 at 19h17, 20h35, et 20h50 UT, respectively, with the OHP Schmidt telescope. Exposures were of 20, 10 et 10min on IIIa-J plates (that used on 2 April was not hypersensitized). North is at the top and East to the left. The vertical field of view is 3.8°. Note the open cluster M34 near the isolated filament on the right-hand panel. The plates were digitized in transparency mode using an Agfa StudioScan II scanner and later processed with an unsharp mask using Photoshop 4.0 for PowerMacintosh.
S.A.Ilovaisky
Modified : 16 Avril 1997