Galaxy Groups and Clusters Observing Guide

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The Hickson Compact Galaxy Groups: 
an atlas comprising DSS images with corresponding MegaStar charts
compiled by Miles Paul

Many observers began using the Hickson’s Atlas of Compact Galaxy Groups as an observing guide when it was published in 1994. As helpful as it was, the "Hickson Atlas" comprises 1950.0 coordinates while the star charts presently used by most amateur observers are based on 2000.0 coordinates, and many of the galaxies in the Atlas are not identified by catalog names. Also, since many of the groups in the Atlas are illustrated as a composite of several exposures, field stars that lie in the gaps between individual images are not shown. These field stars can be helpful when one is hunting for extremely faint objects, as many of the galaxies in the Hickson groups are.

These features detracted from the usefulness of the Atlas of Compact Galaxy Groups as an observing guide. The following is a more "user friendly" atlas of Hickson groups comprising DSS images obtained from SkyView. Text at the top of each atlas page provides catalog identifications derived from MegaStar. Magnitudes (in italics following catalog names) are from the Atlas of Compact Galaxy Groups. The NASA-IPAC Extragalactic Data Base (NED) was the authority to resolve problems in identification when they occurred. Coordinates (2000.0) for the brightest galaxy in each group are in the upper right corner of each chart frame. The size of each image is indicated at the upper right corner of the image.

The atlas of Hickson groups in this guide comprises three DSS images with three MegaStar finder charts per page. In order to reduce congestion, most charts show only a single non-stellar object (usually the brightest galaxy in the Hickson group). Also, at least one star or pattern of stars bright enough to be identified in Uranometria 2000.0 is included , and as a result of this, many of the Hickson groups are not centered on the charts. 

We recommend use of Uranometria 2000.0 to star hop to the area of sky represented on the MegaStar charts, then use the MegaStar charts for the final star hop to the Hickson group. To conserve space, star legends are omitted since relative magnitudes are sufficient for star hopping though a field. Numbers at the lower left of bright stars are magnitudes (e.g., "87" = magnitude 8.7) and the limiting magnitude for stars is 15 unless otherwise indicated. For bright stars, Flamsteed numbers are to the upper right. Double stars brighter than magnitude 12 and with separations less than 20 arcseconds are also included on the charts.

 
Copyright  2006