NOAO/KPNO is operated by the Association of Universities for Research in Astronomy (AURA), Inc. under cooperative agreement with the National Science Foundation
These images of Hale-Bopp are enhanced frames of data taken at the KPNO 4m Mayall telescope on the evening of April 9, 1997. The original field size was 16'x16' with a scale of 0.47"/pixel - these pictures show a 8'x8' (i.e., 2.4 x 105 km square) subset of that field. The original pictures were 0.1s exposures in broad-band R and C (the latter is a blue filter centered near 4000Å) and 1s in an H alpha filter. The left and middle pictures were made by first filtering and then combining all three original images in different ways (the green vertical jets in the comet nucleus in the left image and a similar pattern but in blue in the middle image are caused by saturation or over exposure of the nucleus in the R filter). The right frame is a combination of only the C and H alpha images so as to avoid the over exposure (bad saturation) in the R image that is seen in the first two images. The horizontal trail seen at some level in all three frames is an artifact of the processing.
The partial ring structures in the images are caused by the rotation of the comet nucleus. These rings are mainly representative of dust distribution in the coma.
The images are taken and processed by D. Geisler (KPNO) and M. G. Lee (Seoul National University, Korea).
The image enhancements were done by Nigel