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Welcome to the APM Catalogue Home Page

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• A brief description of the APM facility including overview of system and modes of operation.

• Description of the APM on-line sky catalogues based on APM measurements of Palomar Schmidt and UK Schmidt telescope blue and red sky survey plates.

• To access the APMCAT sky catalogues click here .

• For information about remote interrogation of the catalogues from your local host click here .

• For notes on how to interpret the APM digital finding charts click here .

• For a brief description of the parameters in the lists click here .

• The current coverage of the APM Palomar Schmidt sky catalogue and the APM UK Schmidt sky catalogue .

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• All APM catalogue J2000 astrometry is now based on Tycho-2. External comparison with the ICRF VLBI standards gives the following results from 126 UKST and 231 POSSI matches within 2.5 arcsec:-

  UKST catalogue median offsets for RA and Dec are -0.06 and 0.06 arcsec with scatter about medians of 0.18 and 0.22 arcsec

  POSSI catalogue median offsets for RA and Dec are -0.05 and 0.05 arcsec with sigma about medians of 0.27 and 0.31 arcsec

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This page is maintained by Mike Irwin .