next up previous
Next: Names Up: No Title Previous: No Title

Star Positions

The grid stars were selected at approximately 1 hour intervals in Right Ascension and 15 degrees in Declination, with alternate hour zones offset in declination. The positions are all given to equinox J2000.0, and epoch for each is given in the table. All star positions given in these tables are extracted from astrometric catalogues . The majority of the stars were selected from the CMC catalogue. When there were no suitable stars in the CMC catalogue, the Hipparcos catalogue was searched. There is less choice using Hipparcos, as most of the stars are too bright, so some of the stars are furthur from their ideal grid position than they were in the previous grids. Each star was checked on the STScI Digitised Sky Survey to ensure that there is no other star of brighter or similar magnitude within 2 arcminutes. The stars were also checked on the US Naval Observatory Catalogue on their www page, and the B and R magnitudes were noted. In cases where a star was not included in the USNO catalogue the APM catalogue was used. Stars with very extreme colours were rejected. In a few cases it was not possible to find a colour, so the star was was checked on the red and blue sky sky survey, to check that it did not appear unusual. The visual magnitude is that given in the astrometric catalogue.



Thu Mar 19 22:00:21 GMT 1998