zzzqpart.txt, February 2003 289 SUITABLE ACQUISITION/GUIDE STARS IN A 40' REGION CENTERED NEAR ETA CARINAE List is copied below -- first, though, some explanatory notes: These are excerpted from HST special catalog "ZZZQ" prepared in 1990 by K. Davidson, intended specifically for HST acquisitions in the vicinity of Eta Car because the original HST Guide Star Catalog was obviously inadequate there. The Minnesota Automated Plate Scanner (APS, http://aps.umn.edu) was used to scan three photographic plates taken in 1937, 1985, and 1986, and the image qualities were also assessed by eye. Catalog ZZZQ included about 2200 stars in a 0.7-degree diameter region. Positions are listed here in J2000 coordinates, originally linked to the FK4 system. Internal consistency was usually of the order of 0.3" between different plates, but the overall accuracy has never been studied and errors worse than 0.3" are possible. A few notes on a comparison with the Tycho catalog are given following the list. We have used ZZZQ for HST acquisitions of Eta Car many times since 1990, and so far have never had an acquisition failure. The systematic offset between coordinate systems appears to be RA(Tycho) = RA(ZZZQ) - 0.08s, dec(Tycho) = dec(ZZZQ) + 0.08", (see later below). "Magnitudes" listed here are merely crude values estimated by the APS for each plate; intended for mutual comparisons only, they are not on any particular photometric system. In most cases consider them to be some sort of compromise between B and V magnitudes (?). Note that the list does not include the brightest stars in this region; the magnitude range here is favorable for acquisition/ guide stars with moderately large telescopes. "Quality" in the list refers to the reliability of each star for the purpose of acquisition or telescope guiding. Stars rated below 'C', not included here, showed signs of being double or diffuse, or had detectable proper motions or other disadvantages. Eta Carinae itself and two stars about 14" northeast of it have been inserted into this list, between original ID numbers 1504 and 1532. Their positions were estimated with a combination of ground-based CCD images and HST/WFPC2 images. They have been arbitrarily assigned ID numbers 7777, 8888, 9999. 21 stars marked "Tycho" in the notes column occur in the Tycho (Hipparchus/Tycho) catalog with astrometric quality better than 9. A comparison of this list with the Tycho catalog is outlined in notes following the list. If you use this list for planning or observational purposes, you should acknowledge it in any resulting publications: K. Davidson & R.M. Humphreys (1990), "APS Special Catalog ZZZQ," see http://etacar.umn.edu. The stars are listed in decreasing order of declination. ===-=== ----------------------------------------------------- ID RA DEC mag quality notes 14 10 44 42.93 -59 20 45.2 12.3 A 27 10 44 40.64 -59 21 13.7 11.5 A 35 10 44 30.82 -59 21 26.1 11.4 C Tycho 53 10 44 42.84 -59 21 51.3 11.0 B Tycho 64 10 45 48.30 -59 22 4.5 12.6 B 80 10 45 37.94 -59 22 18.2 12.7 C 95 10 46 12.43 -59 22 36.1 11.3 C 121 10 44 42.40 -59 23 4.0 9.9 B Tycho 136 10 45 40.46 -59 23 15.7 9.6 B Tycho 186 10 46 4.06 -59 24 1.3 12.6 B 208 10 44 36.41 -59 24 20.6 11.0 A 217 10 46 28.26 -59 24 25.5 12.3 A 228 10 44 1.87 -59 24 34.0 10.8 B 238 10 43 35.52 -59 24 45.8 12.6 C 279 10 44 17.97 -59 25 20.6 11.5 A 308 10 44 10.61 -59 25 47.7 10.1 B Tycho 309 10 44 0.69 -59 25 49.4 10.2 A Tycho 318 10 43 23.71 -59 25 59.7 12.8 B 319 10 46 41.90 -59 25 59.8 12.9 C 320 10 45 12.39 -59 26 0.7 12.9 C 329 10 46 38.83 -59 26 11.0 12.6 C 333 10 44 30.29 -59 26 13.2 11.1 B 358 10 44 21.62 -59 26 44.6 10.4 A Tycho 371 10 43 55.44 -59 26 55.6 12.8 C 376 10 44 47.41 -59 26 59.8 12.9 B 383 10 44 20.62 -59 27 4.6 11.5 A 387 10 44 5.81 -59 27 8.3 12.9 C 435 10 44 53.04 -59 27 51.9 10.9 A 466 10 44 50.27 -59 28 10.9 12.9 C 476 10 44 25.24 -59 28 16.4 11.3 A 477 10 44 28.91 -59 28 17.1 12.7 B 489 10 43 53.96 -59 28 23.7 12.2 A 495 10 45 3.50 -59 28 28.0 11.6 B 509 10 46 53.13 -59 28 37.0 13.0 C 525 10 45 31.84 -59 28 46.2 11.6 A 532 10 46 12.47 -59 28 53.8 11.5 B 537 10 44 26.04 -59 28 59.8 12.7 B 542 10 43 17.58 -59 29 3.6 12.6 B 568 10 43 39.14 -59 29 22.4 10.8 A 570 10 43 30.92 -59 29 24.0 9.8 B Tycho 580 10 44 37.76 -59 29 32.1 12.9 B 584 10 43 46.12 -59 29 34.1 11.4 A 586 10 44 2.53 -59 29 37.0 10.0 B Tycho 612 10 45 19.31 -59 29 52.5 12.4 A 618 10 45 15.96 -59 29 56.5 12.2 B 625 10 44 8.32 -59 29 59.8 11.1 A 640 10 43 58.49 -59 30 9.8 12.7 B 653 10 46 45.16 -59 30 17.8 12.2 A 675 10 45 44.23 -59 30 35.8 12.9 B 676 10 44 24.69 -59 30 36.2 10.8 A 678 10 44 31.39 -59 30 38.2 12.6 B 690 10 46 37.76 -59 30 48.9 12.4 B 696 10 44 57.35 -59 30 55.1 11.2 A 768 10 46 4.81 -59 31 58.8 12.8 B 769 10 43 55.12 -59 31 59.0 12.9 C 801 10 46 15.29 -59 32 17.8 10.8 B Tycho 804 10 46 37.35 -59 32 18.7 8.9 B Tycho 809 10 42 53.85 -59 32 20.4 12.5 A 820 10 44 2.78 -59 32 28.7 12.7 B 827 10 45 24.22 -59 32 36.1 12.9 C 840 10 44 43.53 -59 32 42.9 10.9 A 841 10 45 49.72 -59 32 43.4 11.5 A 842 10 42 47.51 -59 32 43.7 11.4 B 844 10 44 18.00 -59 32 44.3 12.6 C 851 10 44 48.92 -59 32 50.6 12.6 B 858 10 44 37.58 -59 32 55.7 9.0 B Tycho 864 10 47 26.82 -59 32 59.9 12.8 B 868 10 46 19.81 -59 33 2.2 10.6 A Tycho 869 10 44 56.37 -59 33 3.6 10.4 B 871 10 44 46.21 -59 33 4.4 12.9 B 876 10 42 54.54 -59 33 7.8 12.7 C 880 10 44 25.56 -59 33 9.6 11.2 B 900 10 42 35.33 -59 33 22.4 12.6 C 902 10 44 52.61 -59 33 23.2 9.2 B Tycho 914 10 46 5.95 -59 33 30.5 10.5 A Tycho 930 10 44 35.57 -59 33 42.9 12.6 C 934 10 45 7.66 -59 33 45.4 12.6 B 938 10 43 44.00 -59 33 46.3 11.5 B 952 10 44 26.82 -59 33 51.2 12.8 B 959 10 46 4.35 -59 33 53.4 10.2 B Tycho 970 10 45 26.59 -59 33 58.1 12.9 C 975 10 44 32.30 -59 33 59.7 12.0 A 999 10 42 50.44 -59 34 13.7 12.7 C 1023 10 46 54.70 -59 34 23.4 12.5 B 1037 10 47 37.07 -59 34 30.5 11.2 A 1053 10 43 56.11 -59 34 41.2 12.6 B 1076 10 42 47.02 -59 34 55.9 12.0 A 1080 10 45 58.59 -59 35 1.1 12.8 B 1087 10 43 33.46 -59 35 11.2 9.7 B Tycho 1088 10 44 5.90 -59 35 11.8 11.4 B 1090 10 44 3.58 -59 35 12.7 12.2 B 1094 10 44 36.52 -59 35 15.1 11.3 A 1105 10 43 59.96 -59 35 24.4 11.2 B 1107 10 44 24.54 -59 35 25.5 12.4 B 1110 10 43 19.10 -59 35 26.0 12.6 C 1132 10 45 55.58 -59 35 41.2 13.0 B 1137 10 43 27.05 -59 35 44.6 12.8 B 1180 10 44 29.47 -59 36 15.9 12.9 B 1186 10 47 30.46 -59 36 20.8 12.9 B 1189 10 43 55.07 -59 36 24.3 12.5 B 1196 10 46 56.03 -59 36 32.1 11.3 A 1206 10 44 57.62 -59 36 39.1 10.9 B 1207 10 45 41.23 -59 36 39.4 13.0 B 1234 10 43 52.31 -59 36 58.9 12.2 B 1236 10 46 35.78 -59 37 0.6 9.8 B Tycho 1244 10 45 23.69 -59 37 9.9 12.6 B 1257 10 43 26.59 -59 37 25.1 10.2 B 1273 10 44 3.27 -59 37 38.0 12.7 B 1275 10 46 45.59 -59 37 38.5 12.8 C 1276 10 45 22.18 -59 37 38.6 11.4 A 1284 10 42 27.26 -59 37 45.1 13.0 B 1286 10 47 27.92 -59 37 46.9 11.3 B 1287 10 44 53.83 -59 37 48.3 11.6 B 1320 10 47 18.25 -59 38 17.9 12.8 B 1322 10 47 3.40 -59 38 20.7 12.6 B 1330 10 46 9.88 -59 38 26.9 12.9 B 1347 10 44 29.50 -59 38 37.9 12.1 C 1359 10 46 5.62 -59 38 49.4 12.7 B 1369 10 43 57.16 -59 38 57.8 12.5 B 1372 10 43 32.59 -59 39 0.4 11.6 A 1390 10 46 17.16 -59 39 19.8 11.3 B 1392 10 47 38.46 -59 39 21.9 12.1 C 1399 10 44 22.60 -59 39 25.5 11.1 B 1412 10 45 19.49 -59 39 37.4 12.3 B 1415 10 46 20.01 -59 39 38.5 11.8 B 1426 10 46 44.67 -59 39 48.0 12.5 A 1431 10 45 43.71 -59 39 54.1 12.9 B 1433 10 43 59.35 -59 39 56.4 12.7 B 1434 10 45 16.57 -59 39 56.8 10.9 B 1442 10 42 45.30 -59 40 2.0 12.8 B 1446 10 45 23.20 -59 40 3.4 12.2 B 1455 10 45 9.73 -59 40 8.5 12.4 C 1460 10 44 41.05 -59 40 10.2 11.2 B 1471 10 44 28.18 -59 40 16.2 12.8 C 1486 10 44 1.66 -59 40 25.4 12.8 B 1489 10 44 46.06 -59 40 29.5 12.2 A 1504 10 45 34.85 -59 40 43.7 12.9 C 7777 10 45 04.851 -59 40 53.68 12: X NE1 star 8888 10 45 05.228 -59 40 57.37 12: X NE2 star 9999 10 45 03.643 -59 41 04.22 7: X Eta A 1532 10 42 42.47 -59 41 5.9 12.8 C 1538 10 45 31.39 -59 41 13.3 12.8 B 1543 10 44 8.95 -59 41 17.3 12.0 B 1554 10 42 26.16 -59 41 24.5 11.2 B 1572 10 44 30.60 -59 41 40.5 11.0 B 1583 10 45 21.12 -59 41 44.5 12.9 B 1584 10 43 56.66 -59 41 45.7 12.5 B 1592 10 44 40.38 -59 41 48.7 10.5 B 1601 10 42 53.50 -59 41 52.3 12.6 B 1609 10 45 6.81 -59 41 56.5 10.0 B 1645 10 46 3.67 -59 42 16.4 12.4 A 1653 10 44 58.96 -59 42 23.0 11.6 B 1658 10 46 35.56 -59 42 26.0 12.8 B 1662 10 44 18.37 -59 42 29.6 12.7 C 1670 10 44 44.38 -59 42 33.2 12.8 B 1672 10 44 29.06 -59 42 34.2 12.2 B 1675 10 45 6.42 -59 42 35.8 11.9 B 1695 10 45 12.72 -59 42 48.7 11.2 B 1696 10 45 20.64 -59 42 51.2 10.0 B 1703 10 45 9.81 -59 42 57.1 11.6 A 1726 10 45 5.92 -59 43 7.7 9.8 B 1733 10 42 53.40 -59 43 9.0 12.6 B 1739 10 44 13.28 -59 43 10.2 10.8 B 1742 10 44 51.66 -59 43 13.6 12.8 B 1743 10 45 16.77 -59 43 14.1 12.0 B 1745 10 44 59.97 -59 43 14.9 11.9 B 1746 10 42 48.84 -59 43 15.3 12.7 B 1758 10 44 45.13 -59 43 25.9 11.9 A 1772 10 47 29.83 -59 43 33.2 11.6 B 1776 10 45 0.31 -59 43 34.5 11.5 B 1779 10 45 16.61 -59 43 37.0 9.2 B 1780 10 43 52.95 -59 43 37.2 12.3 A 1791 10 44 15.29 -59 43 43.8 9.3 B 1810 10 43 7.24 -59 44 0.9 12.5 B 1833 10 46 58.84 -59 44 13.4 11.1 B 1846 10 45 5.94 -59 44 18.9 11.4 B 1848 10 45 12.98 -59 44 19.2 9.2 B 1852 10 44 52.27 -59 44 21.3 12.5 B 1879 10 43 30.39 -59 44 45.0 12.7 C 1926 10 42 33.15 -59 45 14.8 11.8 B 1933 10 44 55.72 -59 45 17.7 13.0 C 1941 10 44 27.92 -59 45 21.5 9.8 B 1953 10 46 11.88 -59 45 32.0 11.3 A 1966 10 43 26.23 -59 45 42.9 13.0 B 1983 10 46 0.05 -59 45 59.5 12.8 B 1987 10 47 20.80 -59 46 4.8 12.9 C 1990 10 45 13.03 -59 46 6.0 13.0 C 1994 10 44 23.59 -59 46 7.0 12.7 B 2016 10 46 48.82 -59 46 24.4 12.2 B 2039 10 45 59.92 -59 46 35.2 12.9 B 2048 10 46 13.02 -59 46 44.0 12.8 C 2051 10 44 18.22 -59 46 46.3 12.5 B 2052 10 44 15.65 -59 46 47.5 12.3 B 2056 10 44 6.77 -59 46 50.4 12.8 B 2066 10 43 19.06 -59 46 56.9 11.4 B 2082 10 46 15.75 -59 47 8.4 13.0 B 2086 10 46 6.01 -59 47 11.1 11.2 A 2092 10 45 33.74 -59 47 14.7 12.5 A 2105 10 44 36.79 -59 47 29.6 10.9 A 2106 10 47 9.31 -59 47 29.9 9.4 B 2124 10 47 31.57 -59 47 42.5 10.9 B 2128 10 45 43.83 -59 47 46.8 13.0 C 2146 10 44 29.77 -59 47 56.1 12.9 B 2148 10 44 12.36 -59 47 57.1 10.9 A 2175 10 44 38.76 -59 48 14.0 10.2 A 2176 10 44 3.81 -59 48 14.1 12.7 B 2177 10 42 40.21 -59 48 14.1 12.0 A 2180 10 43 44.10 -59 48 17.8 9.8 B Tycho 2187 10 45 17.64 -59 48 20.9 12.3 B 2190 10 45 36.38 -59 48 23.3 12.3 A 2196 10 47 4.42 -59 48 28.5 12.8 C 2198 10 45 2.98 -59 48 29.3 12.6 B 2217 10 45 21.64 -59 48 45.8 12.4 B 2233 10 43 4.25 -59 48 58.9 12.7 B 2235 10 45 57.16 -59 48 59.5 12.9 C 2245 10 45 52.49 -59 49 7.4 11.4 B 2257 10 45 19.87 -59 49 13.7 12.6 C 2275 10 46 28.15 -59 49 20.7 11.2 A 2276 10 44 58.86 -59 49 21.0 11.6 A 2277 10 46 4.85 -59 49 21.7 11.6 B 2284 10 47 7.14 -59 49 25.6 12.4 A 2291 10 46 44.12 -59 49 30.5 12.9 C 2318 10 44 36.67 -59 49 47.5 11.7 A 2319 10 47 4.43 -59 49 48.3 12.9 C 2326 10 46 13.90 -59 49 51.8 11.2 B 2327 10 44 0.81 -59 49 51.9 12.5 B 2350 10 44 57.57 -59 50 3.7 12.9 C 2373 10 47 3.12 -59 50 19.5 12.3 A 2375 10 43 33.68 -59 50 21.9 12.5 B 2395 10 45 48.52 -59 50 34.4 11.3 B 2400 10 46 55.64 -59 50 39.2 12.9 C 2402 10 45 44.67 -59 50 41.0 12.4 A 2409 10 43 48.19 -59 50 44.5 12.7 B 2412 10 45 22.36 -59 50 47.0 11.2 A 2419 10 47 6.01 -59 50 53.0 12.0 A 2439 10 43 15.82 -59 51 5.6 9.8 B 2457 10 43 6.92 -59 51 20.3 12.3 A 2462 10 46 1.70 -59 51 21.0 11.6 B 2473 10 45 5.39 -59 51 30.9 12.4 A 2500 10 44 18.88 -59 51 49.0 12.2 A 2508 10 44 53.60 -59 51 53.9 11.6 A 2510 10 42 41.85 -59 51 54.8 11.7 B 2540 10 43 17.16 -59 52 9.0 12.9 C 2544 10 44 30.17 -59 52 14.0 11.1 B 2550 10 42 45.25 -59 52 19.7 9.3 B 2586 10 43 5.32 -59 52 43.0 10.9 A 2595 10 45 15.36 -59 52 47.5 12.9 C 2598 10 43 25.91 -59 52 48.6 11.2 A 2619 10 46 8.33 -59 53 5.8 12.6 B 2620 10 44 27.67 -59 53 5.8 8.7 B 2630 10 45 4.98 -59 53 14.8 12.7 B 2638 10 46 22.55 -59 53 20.7 10.5 A 2643 10 43 45.16 -59 53 25.4 10.6 A 2644 10 43 36.59 -59 53 25.7 12.9 B 2645 10 45 9.50 -59 53 27.1 13.0 C 2649 10 45 25.87 -59 53 30.8 12.6 C 2666 10 46 59.67 -59 53 46.9 12.7 C 2670 10 44 43.12 -59 53 48.7 11.5 A 2699 10 43 6.29 -59 54 11.2 13.0 C 2701 10 44 23.56 -59 54 13.2 12.8 C 2717 10 44 36.88 -59 54 24.9 9.6 B 2725 10 44 48.11 -59 54 29.6 12.3 A 2727 10 43 19.08 -59 54 31.2 12.9 C 2731 10 45 4.37 -59 54 35.5 12.0 A 2739 10 46 29.01 -59 54 39.4 12.9 C 2741 10 44 45.33 -59 54 41.6 9.5 B 2743 10 45 16.81 -59 54 45.9 10.5 B 2754 10 44 29.93 -59 54 52.2 12.8 C 3022 10 43 39.83 -59 55 16.5 12.0 C 3023 10 44 11.37 -59 55 30.7 9.6 B 3026 10 45 31.75 -59 55 44.8 12.7 B 3027 10 44 50.50 -59 55 44.9 10.8 B 3028 10 45 11.05 -59 55 51.7 12.3 B 3034 10 43 48.17 -59 56 13.7 12.9 B 3035 10 44 21.19 -59 56 20.8 13.0 C 3037 10 46 6.17 -59 56 34.0 12.0 B 3039 10 45 57.20 -59 56 43.4 11.7 B 3041 10 45 53.77 -59 57 4.0 10.1 B 3042 10 45 0.59 -59 57 8.3 12.9 B 3044 10 45 58.85 -59 57 20.7 12.6 B 3045 10 44 50.64 -59 57 22.5 12.3 B 3047 10 43 49.48 -59 57 22.6 10.9 B Tycho 3048 10 45 34.11 -59 57 26.7 10.2 C 3051 10 45 13.43 -59 57 53.8 10.5 B 3052 10 46 19.23 -59 57 54.7 11.7 C 3053 10 44 47.58 -59 57 58.8 9.7 B Tycho 3056 10 45 59.07 -59 58 10 12.7 C 3059 10 44 8.81 -59 58 23.2 12.1 B 3061 10 46 5.02 -59 59 2.1 12.4 C 3064 10 44 39.59 -59 59 33.0 9.8 B 3068 10 44 35.55 -59 59 54.3 11.7 B 3070 10 44 15.04 -60 0 6.1 9.5 B ===-=== ----------------------------------------------------- Comparisons with the Tycho (Hipparcos/Tycho) Catalog: 21 stars in this list also appear in the Tycho Catalog with astrometric quality ratings better than 9. The average difference between positions is: RA(Tycho) = RA(ZZZQ) - 0.08s with r.m.s.dev = +/- 0.020s, dec(Tycho) = dec(ZZZQ) + 0.08" with r.m.s.dev = +/- 0.16". When this offset is allowed for, the r.m.s. difference in position between the Tycho and ZZZQ positions is 0.22" which is about as good as expected. For three of those 21 stars, the ZZZQ magnitude is smaller (brighter) than the Tycho magnitude by 1.0 or more. Possibly this is related to the colors. An additional 39 of the above stars appear in the Tycho Catalog with the lowest astrometric quality rating there, 9. Several of them show surprising position discrepancies (0.7" to 2") between the two lists. We suspect that something is seriously wrong with the Tycho positions in at least some of these cases, since the better-rated Tycho stars are all consistent with ZZZQ as noted above. ===-=== ----------------------------------------------------- 2000 May 15 List adapted from file may2000.003 by program specialx.c