IOTA/IOTA-ES occultation update for (951) Gaspra / TYC 0587-00858-1 event on 2009 Jan 09, 00:26 UT Visible from Summary ------- On 2009 Jan 09 UT, the 16 km diameter asteroid (951) Gaspra will occult a 10.2 mag star in the constellation Pisces for observers along a path across . In the case of an occultation, the combined light of the asteroid and the star will drop by 5.3 mag to 15.5 mag (the magnitude of the asteroid) for at most 0.5 seconds. This update is based on UNSO/Flagstaff astrometry for the asteroid kindly provided by Alice Monet, historical astrometry from the MPC files (via AstDys), and the following catalogs for the star position: UCAC. The event at a glimpse ---------------------- * Rank: 26 * date and approx. time of event: 2009 Jan 09, 00:27 - 2009 Jan 09, 00:30 UT * magnitude of target star: 10.2 * magnitude drop [mag]: 5.3 * estimated maximum duration [s]: 0.5 * Moon: 93 % sunlit, 79° distance * Sun: 71° distance * rough path description: Additional comments ------------------- 15" double star The occultation path -------------------- * approximate projected width [km]: 16 * 1 sigma uncertainty interval [path widths]: +/- 2.61 * 1 sigma uncertainty interval [seconds]: +/- 1.6 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .036 +/- .031) * 1 sigma uncertainty ellipse (major, minor, PA): ( .036", .031", 85° ) * approx speed of asteroid's shadow [km/s]: 30.7186 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 0587-00858-1 by 951 Gaspra on 2009 Jan 9 Centre Star Star Sun Path Limits Error Limits E. Longitude Latitude U.T. Alt Az Alt Limit 1 Limit 2 Limit 3 Limit 4 o ' " o ' " h m s o o o o ' " o ' " o ' " o ' " Latitude Latitude Latitude Latitude -102 0 0 18 41 36 0 27 50 68 224 -1 18 36 56 18 46 16 18 12 37 19 10 38 -101 0 0 19 1 9 0 27 54 67 225 -2 18 56 30 19 5 49 18 32 12 19 30 9 -100 0 0 19 20 30 0 27 57 66 227 -3 19 15 51 19 25 10 18 51 34 19 49 29 - 99 0 0 19 39 39 0 28 1 65 228 -4 19 35 0 19 44 18 19 10 45 20 8 36 - 98 0 0 19 58 35 0 28 4 64 229 -5 19 53 56 20 3 14 19 29 42 20 27 30 - 97 0 0 20 17 18 0 28 7 63 230 -6 20 12 40 20 21 56 19 48 27 20 46 11 - 96 0 0 20 35 48 0 28 11 63 231 -7 20 31 9 20 40 26 20 6 59 21 4 39 - 95 0 0 20 54 3 0 28 14 62 232 -8 20 49 26 20 58 41 20 25 16 21 22 53 - 94 0 0 21 12 5 0 28 17 61 233 -9 21 7 28 21 16 43 20 43 20 21 40 54 - 93 0 0 21 29 53 0 28 20 60 234 -10 21 25 16 21 34 30 21 1 10 21 58 39 - 92 0 0 21 47 26 0 28 23 59 235 -11 21 42 49 21 52 3 21 18 45 22 16 11 - 91 0 0 22 4 45 0 28 27 58 236 -12 22 0 8 22 9 21 21 36 5 22 33 27 - 90 0 0 22 21 48 0 28 30 57 237 -13 22 17 12 22 26 24 21 53 10 22 50 28 - 89 0 0 22 38 36 0 28 33 56 238 -14 22 34 0 22 43 12 22 10 0 23 7 14 - 88 0 0 22 55 8 0 28 36 55 238 -15 22 50 33 22 59 44 22 26 34 23 23 45 - 87 0 0 23 11 25 0 28 38 54 239 -16 23 6 50 23 16 0 22 42 53 23 39 59 - 86 0 0 23 27 26 0 28 41 53 240 -17 23 22 51 23 32 1 22 58 56 23 55 58 - 85 0 0 23 43 10 0 28 44 52 241 -18 23 38 35 23 47 45 23 14 42 24 11 41 - 84 0 0 23 58 38 0 28 47 51 241 -19 23 54 4 24 3 13 23 30 12 24 27 7 - 83 0 0 24 13 50 0 28 50 50 242 -20 24 9 16 24 18 24 23 45 26 24 42 16 - 82 0 0 24 28 45 0 28 52 49 243 -21 24 24 11 24 33 18 24 0 23 24 57 9 - 81 0 0 24 43 23 0 28 55 49 243 -22 24 38 49 24 47 56 24 15 3 25 11 45 - 80 0 0 24 57 43 0 28 58 48 244 -22 24 53 10 25 2 17 24 29 26 25 26 4 - 79 0 0 25 11 47 0 29 0 47 245 -23 25 7 14 25 16 20 24 43 31 25 40 5 - 78 0 0 25 25 33 0 29 3 46 245 -24 25 21 1 25 30 6 24 57 19 25 53 50 - 77 0 0 25 39 2 0 29 5 45 246 -25 25 34 30 25 43 34 25 10 50 26 7 17 - 76 0 0 25 52 13 0 29 8 44 246 -26 25 47 41 25 56 45 25 24 3 26 20 26 - 75 0 0 26 5 7 0 29 10 43 247 -27 26 0 35 26 9 38 25 36 59 26 33 17 - 74 0 0 26 17 43 0 29 12 42 248 -28 26 13 11 26 22 14 25 49 36 26 45 51 - 73 0 0 26 30 0 0 29 14 41 248 -29 26 25 29 26 34 31 26 1 56 26 58 7 - 72 0 0 26 42 0 0 29 17 40 249 -30 26 37 29 26 46 31 26 13 58 27 10 5 - 71 0 0 26 53 42 0 29 19 39 249 -31 26 49 11 26 58 12 26 25 41 27 21 44 - 70 0 0 27 5 5 0 29 21 38 250 -32 27 0 35 27 9 35 26 37 6 27 33 6 - 69 0 0 27 16 10 0 29 23 38 250 -33 27 11 40 27 20 40 26 48 13 27 44 9 - 68 0 0 27 26 57 0 29 25 37 251 -34 27 22 27 27 31 26 26 59 2 27 54 54 - 67 0 0 27 37 25 0 29 27 36 252 -35 27 32 56 27 41 54 27 9 32 28 5 21 - 66 0 0 27 47 35 0 29 29 35 252 -35 27 43 6 27 52 4 27 19 43 28 15 29 - 65 0 0 27 57 26 0 29 31 34 253 -36 27 52 58 28 1 55 27 29 37 28 25 19 - 64 0 0 28 6 59 0 29 33 33 253 -37 28 2 31 28 11 28 27 39 11 28 34 50 - 63 0 0 28 16 13 0 29 35 32 254 -38 28 11 45 28 20 42 27 48 27 28 44 2 - 62 0 0 28 25 9 0 29 36 31 254 -39 28 20 41 28 29 37 27 57 24 28 52 56 - 61 0 0 28 33 46 0 29 38 30 255 -40 28 29 18 28 38 13 28 6 2 29 1 32 - 60 0 0 28 42 4 0 29 40 29 255 -41 28 37 36 28 46 31 28 14 22 29 9 48 - 59 0 0 28 50 3 0 29 41 29 256 -42 28 45 36 28 54 30 28 22 22 29 17 46 - 58 0 0 28 57 43 0 29 43 28 256 -43 28 53 17 29 2 10 28 30 4 29 25 25 - 57 0 0 29 5 5 0 29 44 27 257 -43 29 0 38 29 9 32 28 37 27 29 32 46 - 56 0 0 29 12 8 0 29 46 26 257 -44 29 7 41 29 16 35 28 44 31 29 39 47 - 55 0 0 29 18 52 0 29 47 25 258 -45 29 14 26 29 23 18 28 51 16 29 46 30 - 54 0 0 29 25 17 0 29 48 24 258 -46 29 20 51 29 29 43 28 57 43 29 52 54 - 53 0 0 29 31 23 0 29 50 23 259 -47 29 26 57 29 35 49 29 3 50 29 58 59 - 52 0 0 29 37 11 0 29 51 22 260 -48 29 32 45 29 41 36 29 9 38 30 4 45 - 51 0 0 29 42 39 0 29 52 22 260 -49 29 38 13 29 47 5 29 15 8 30 10 13 - 50 0 0 29 47 48 0 29 53 21 261 -50 29 43 23 29 52 14 29 20 18 30 15 21 - 49 0 0 29 52 39 0 29 55 20 261 -51 29 48 14 29 57 4 29 25 10 30 20 11 - 48 0 0 29 57 11 0 29 56 19 262 -51 29 52 46 30 1 36 29 29 42 30 24 42 - 47 0 0 30 1 23 0 29 57 18 262 -52 29 56 58 30 5 49 29 33 56 30 28 53 - 46 0 0 30 5 17 0 29 58 17 263 -53 30 0 52 30 9 42 29 37 50 30 32 47 - 45 0 0 30 8 52 0 29 58 16 263 -54 30 4 27 30 13 17 29 41 26 30 36 21 - 44 0 0 30 12 8 0 29 59 15 264 -55 30 7 43 30 16 33 29 44 42 30 39 36 - 43 0 0 30 15 5 0 30 0 15 264 -56 30 10 40 30 19 30 29 47 40 30 42 33 - 42 0 0 30 17 43 0 30 1 14 265 -57 30 13 19 30 22 8 29 50 19 30 45 10 - 41 0 0 30 20 2 0 30 2 13 265 -57 30 15 38 30 24 27 29 52 38 30 47 29 - 40 0 0 30 22 3 0 30 2 12 266 -58 30 17 38 30 26 27 29 54 39 30 49 29 - 39 0 0 30 23 44 0 30 3 11 266 -59 30 19 20 30 28 9 29 56 21 30 51 10 - 38 0 0 30 25 7 0 30 4 10 267 -60 30 20 42 30 29 31 29 57 43 30 52 32 - 37 0 0 30 26 10 0 30 4 9 267 -61 30 21 46 30 30 35 29 58 47 30 53 36 - 36 0 0 30 26 55 0 30 5 8 268 -62 30 22 31 30 31 20 29 59 32 30 54 21 - 35 0 0 30 27 21 0 30 5 8 268 -63 30 22 57 30 31 45 29 59 58 30 54 46 - 34 0 0 30 27 28 0 30 6 7 269 -63 30 23 4 30 31 53 30 0 5 30 54 53 - 33 0 0 30 27 16 0 30 6 6 269 -64 30 22 52 30 31 41 29 59 53 30 54 42 - 32 0 0 30 26 46 0 30 6 5 270 -65 30 22 21 30 31 10 29 59 23 30 54 11 - 31 0 0 30 25 56 0 30 6 4 270 -66 30 21 32 30 30 21 29 58 33 30 53 22 - 30 0 0 30 24 48 0 30 7 3 271 -67 30 20 24 30 29 13 29 57 25 30 52 14 - 29 0 0 30 23 21 0 30 7 2 271 -68 30 18 57 30 27 46 29 55 57 30 50 47 - 28 0 0 30 21 35 0 30 7 2 272 -68 30 17 11 30 26 0 29 54 11 30 49 2 - 27 0 0 30 19 31 0 30 7 1 272 -69 30 15 6 30 23 55 29 52 6 30 46 58 Uncertainty in time = +/- 2 secs [Prediction of 2008 Nov 4.0] Data for the target star ------------------------ * name: TYC 0587-00858-1 * constellation : Pisces * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 23 54 10.9584 DE: +02 18 50.061 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .032, .029 ) * V mag [mag]: 10.2 * B mag [mag]: 11.3 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (951) Gaspra approx. diameter [km]: 16 approx. diameter ["]: .012 distance from Earth [AU]: 1.89800 * orbital information: orbit source: Preston date of fit: 2008 Nov 03 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 1234 number of rejected observations: 57 time covered by the observations: 1913 Dec 19 - 2008 Sep 07 1 sigma uncertainty ellipse (major, minor, PA): 0.017, 0.012, 68° remarks: * orbital elements for (951) Gaspra : Mean anomaly = 5.10475586 deg Arg. of pericenter = 129.52024037 deg Long. of node = 253.20252738 deg Inclination = 4.10124427 deg Eccentricity = 0.17303885 Semimajor axis = 2.20967888 AU Perihelion dist = 1.82731859 AU Mag: H = 11.50, G = 0.15 Epoch of elements : MJD 54840.01900000 TDT (2009 Jan 09.019) ------ occelmnt file for Occult BEGIN ----------------------------------- 2009 Jan 9 951 Gaspra 0h 26.7m UT 10.2 23 54 10.958 2 18 50.06TYC 0587-00858-1 11.3 15.5 16 0.5 1.898 5.046 27.06 -116.8161 2.307 175.08 -22.11 0.4452 -0.06230 0.17048 16.32490 5.84117 0.00449 0.00204 2000 2.09843920081230.00000129.520240253.202527 4.1012440.17303885 2.2096789 1.827318611.5 5.00.15 RATE 3.0006160 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.036 0.031 85 3.61 0.030 0 54774.5020090109_0858-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Nov 04, 05:40 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org