205 V2527 OPHIUCHI (UGSU) Range: 14.4-19V Position: 17 22 04.38 -19 49 08.1 (J2000, from .dat file) Magnitude: V=16.766 B-V=0.546 (.dat file, single night) ID RA (2000) DEC X Y N V ERR B-V ERR a) Comparison star sequence 1 17 21 41.5 -19 43 41 -324 327 1 12.019 0.001 0.762 0.001 2 17 21 44.0 -19 48 46 -288 22 3 13.262 0.058 0.734 0.017 3 17 22 09.6 -19 46 45 74 143 3 13.467 0.063 0.921 0.014 4 17 21 53.7 -19 44 42 -151 266 3 13.988 0.052 1.566 0.011 5 17 21 48.0 -19 43 27 -231 341 3 14.154 0.046 0.815 0.024 6 17 22 05.3 -19 45 30 13 218 3 14.453 0.077 1.376 0.019 7 17 22 01.5 -19 50 24 -41 -76 3 14.812 0.067 1.109 0.017 8 17 22 09.4 -19 49 20 70 -12 3 15.023 0.063 1.387 0.012 9 17 22 09.0 -19 48 35 65 33 3 15.267 0.068 1.469 0.008 10 17 22 01.9 -19 47 00 -35 128 3 15.783 0.082 1.477 0.028 11 17 22 02.9 -19 48 47 -21 21 3 16.265 0.063 1.495 0.047 12 17 22 00.4 -19 48 37 -57 32 2 17.399 0.099 0.897 0.009 13 17 22 03.7 -19 49 09 -10 -1 2 17.557 0.008 1.660 0.119 14 17 22 04.7 -19 49 28 4 -20 1 19.021 0.105 1.093 0.181 b) Wide-colour extension for CCD calibration 17 21 45.8 -19 44 47 -262 261 3 14.634 0.042 0.530 0.024 17 21 58.5 -19 50 37 -84 -88 3 14.305 0.071 2.004 0.027 17 22 18.9 -19 48 54 205 14 3 13.271 0.070 2.023 0.017 Notes: 1. There is a bright star on the northeast edge of this sequence that was too bright to be measured during the photometric determination. This star is located at 17h 21m 51.6s -19d 41' 38" and has a reliable Tycho-2 magnitude of V=10.29+/-0.06. 2. Star #13 is a faint companion to this variable. Star #14 has large errors and is included only for guidance. 3. This variable was measured as bright as V=14.8 during the determination of this sequence. 4. This variable is also known as 2E 1719.1-1946 and RX J172204.5-194913. Bruce Sumner 25 February 2001