275 GY CANCRI (UGSU) Range: 12.0-18.0V Position: 09 09 50.54 +18 49 47.6 (J2000, from .dat file) Magnitude: V=16.274 B-V=0289 (Henden, dat file) ID RA (2000) DEC X Y N V ERR B-V ERR a) Comparison star sequence 1 09 09 59.9 +18 57 15 133 447 2 8.976 0.052 0.447 0.025 2 09 09 34.8 +19 01 14 -222 686 2 9.756 0.004 0.198 0.014 3 09 10 03.2 +18 50 05 180 17 2 11.002 0.004 1.148 0.009 4 09 09 29.4 +18 49 41 -300 -7 2 11.240 0.004 1.090 0.001 5 09 09 56.6 +18 55 38 86 350 2 11.516 0.006 0.821 0.006 6 09 09 23.0 +18 59 53 -390 605 2 12.069 0.006 0.628 0.010 7 09 09 39.2 +18 57 56 -160 488 2 12.352 0.000 0.904 0.003 8 09 09 27.1 +18 46 58 -333 -170 2 12.837 0.006 0.841 0.006 9 09 09 45.2 +18 47 38 -76 -130 3 13.465 0.008 0.498 0.011 10 09 09 57.8 +18 49 03 103 -45 3 13.740 0.005 0.538 0.015 11 09 09 37.3 +18 56 31 -187 403 2 14.069 0.006 0.739 0.013 12 09 10 14.8 +18 42 41 346 -427 2 14.507 0.006 1.164 0.000 13 09 09 10.9 +18 57 03 -562 435 2 14.839 0.006 0.594 0.011 14 09 10 11.4 +18 49 54 297 6 3 15.428 0.019 0.749 0.028 15 09 10 00.3 +18 46 28 139 -200 3 16.039 0.006 0.641 0.023 16 09 09 49.4 +18 50 42 -16 54 3 16.585 0.027 0.960 0.049 17 09 09 46.2 +18 50 00 -61 12 3 16.864 0.031 0.935 0.097 18 09 10 01.4 +18 51 32 155 104 3 18.053 0.052 0.600 0.077 b) Wide-colour extension for CCD calibration 09 09 36.7 +18 46 36 -195 -192 3 16.171 0.017 0.497 0.030 09 09 38.3 +18 47 10 -173 -158 3 16.462 0.041 1.468 0.033 Notes: 1. Stars #1 and #2 are both saturated and the magnitudes are only approximate. However they do both have reliable Tycho-2 magnitudes of V=8.94+/-0.01 and V=9.81+/-0.03 respectively. 2. A DSS outburst image where GY Cnc is about magnitude 12.5 seems to show an elongated image. It is possible that GY Cnc is a close double. 3. This variable was previously known as 1RXS J090950.6+184956. The minimum magnitude of 18.0V given above is from Namelist 76. Bruce Sumner 4 April 2002 Revised 20 April 2002