IOTA/IOTA-ES occultation update for (2137) Priscilla / UCAC2 18789908 event on 2009 Jul 04, 04:23 UT Visible from Africa, SE USA Summary ------- On 2009 Jul 04 UT, the 41 km diameter asteroid (2137) Priscilla will occult a 11.7 mag star in the constellation Sagittarius for observers along a path across Africa, SE USA. In the case of an occultation, the combined light of the asteroid and the star will drop by 4.2 mag to 15.9 mag (the magnitude of the asteroid) for at most 3.0 seconds. This update is based on UNSO/Flagstaff astrometry for the asteroid kindly provided by Alice Monet, TMO astrometry for the asteroid kindly provided by Bill Owen, historical astrometry from the MPC files (via AstDys), and the following catalogs for the star position: UCAC. The event at a glimpse ---------------------- * Rank: 22 * date and approx. time of event: 2009 Jul 04, 04:17 - 2009 Jul 04, 04:26 UT * magnitude of target star: 11.7 * magnitude drop [mag]: 4.2 * estimated maximum duration [s]: 3.0 * Moon: 91 % sunlit, 40° distance * Sun: 169° distance * rough path description: Africa, SE USA The occultation path -------------------- * approximate projected width [km]: 68 * 1 sigma uncertainty interval [path widths]: +/- 3.04 * 1 sigma uncertainty interval [seconds]: +/- 8.0 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .075 +/- .073) * 1 sigma uncertainty ellipse (major, minor, PA): ( .075", .073", 78° ) * approx speed of asteroid's shadow [km/s]: 13.8112 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of UCAC2 18789908 by 2137 Priscilla on 2009 Jul 4 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 ' " Longitude Longitude Longitude Longitude -110 53 49 43 0 0 4 26 50 1 137 -12 -110 17 54 -111 29 28 -106 33 12 ... .. .. -109 32 51 42 0 0 4 26 49 3 138 -14 -108 56 52 -110 8 34 -105 11 25 ... .. .. -108 10 14 41 0 0 4 26 48 4 139 -15 -107 34 7 -108 46 3 -103 47 30 ... .. .. -106 45 46 40 0 0 4 26 47 5 140 -16 -106 9 27 -107 21 47 -102 21 10 ... .. .. -105 19 16 39 0 0 4 26 44 7 141 -18 -104 42 40 -105 55 31 -100 52 12 ... .. .. -103 50 29 38 0 0 4 26 42 8 142 -19 -103 13 32 -104 27 4 - 99 20 18 ... .. .. -102 19 9 37 0 0 4 26 38 10 143 -21 -101 41 45 -102 56 10 - 97 45 4 ... .. .. -100 44 59 36 0 0 4 26 35 12 144 -22 -100 7 2 -101 22 31 - 96 6 8 ... .. .. - 99 7 37 35 0 0 4 26 30 13 145 -24 - 98 28 59 - 99 45 48 - 94 22 59 -103 29 13 - 97 26 40 34 0 0 4 26 24 15 146 -26 - 96 47 13 - 98 5 37 - 92 34 59 -101 52 53 - 95 41 37 33 0 0 4 26 18 16 147 -27 - 95 1 10 - 96 21 30 - 90 41 24 -100 13 26 - 93 51 52 32 0 0 4 26 11 18 148 -29 - 93 10 14 - 94 32 53 - 88 41 14 - 98 30 26 - 91 56 41 31 0 0 4 26 3 20 149 -31 - 91 13 36 - 92 39 4 - 86 33 12 - 96 43 23 - 89 55 9 30 0 0 4 25 54 21 151 -32 - 89 10 16 - 90 39 12 - 84 15 35 - 94 51 43 Latitude Latitude Latitude Latitude - 89 0 0 29 33 54 4 25 49 22 151 -33 29 55 10 29 12 50 32 9 8 27 8 41 - 88 0 0 29 6 19 4 25 44 23 152 -34 29 27 25 28 45 24 31 40 14 26 42 9 - 87 0 0 28 39 33 4 25 39 24 153 -35 29 0 29 28 18 49 31 12 13 26 16 26 - 86 0 0 28 13 38 4 25 34 25 153 -35 28 34 25 27 53 2 30 45 6 25 51 30 - 85 0 0 27 48 33 4 25 28 25 154 -36 28 9 11 27 28 6 30 18 52 25 27 22 - 84 0 0 27 24 18 4 25 23 26 155 -37 27 44 47 27 3 59 29 53 30 25 4 2 - 83 0 0 27 0 52 4 25 17 27 156 -37 27 21 14 26 40 42 29 29 2 24 41 29 - 82 0 0 26 38 17 4 25 11 27 156 -38 26 58 31 26 18 14 29 5 26 24 19 44 - 81 0 0 26 16 32 4 25 6 28 157 -39 26 36 38 25 56 36 28 42 43 23 58 47 - 80 0 0 25 55 37 4 25 0 29 158 -39 26 15 35 25 35 48 28 20 53 23 38 38 - 79 0 0 25 35 31 4 24 53 29 159 -40 25 55 23 25 15 49 27 59 55 23 19 16 - 78 0 0 25 16 15 4 24 47 30 160 -40 25 36 1 24 56 40 27 39 49 23 0 42 - 77 0 0 24 57 49 4 24 41 31 160 -41 25 17 28 24 38 19 27 20 36 22 42 56 - 76 0 0 24 40 12 4 24 35 31 161 -41 24 59 46 24 20 48 27 2 14 22 25 57 - 75 0 0 24 23 25 4 24 28 32 162 -42 24 42 53 24 4 7 26 44 44 22 9 46 - 74 0 0 24 7 27 4 24 21 32 163 -42 24 26 49 23 48 14 26 28 6 21 54 22 - 73 0 0 23 52 18 4 24 15 33 164 -43 24 11 36 23 33 10 26 12 19 21 39 45 - 72 0 0 23 37 59 4 24 8 33 165 -43 23 57 11 23 18 55 25 57 24 21 25 55 - 71 0 0 23 24 28 4 24 1 34 166 -43 23 43 36 23 5 28 25 43 20 21 12 53 - 70 0 0 23 11 46 4 23 55 34 167 -44 23 30 51 22 52 51 25 30 7 21 0 38 - 69 0 0 22 59 53 4 23 48 34 168 -44 23 18 54 22 41 1 25 17 45 20 49 10 - 68 0 0 22 48 49 4 23 41 35 169 -44 23 7 46 22 30 1 25 6 14 20 38 29 - 67 0 0 22 38 34 4 23 34 35 169 -45 22 57 28 22 19 49 24 55 34 20 28 34 - 66 0 0 22 29 7 4 23 27 35 170 -45 22 47 58 22 10 25 24 45 44 20 19 27 - 65 0 0 22 20 29 4 23 20 36 171 -45 22 39 17 22 1 49 24 36 45 20 11 6 - 64 0 0 22 12 39 4 23 12 36 172 -45 22 31 24 21 54 1 24 28 36 20 3 32 - 63 0 0 22 5 37 4 23 5 36 173 -45 22 24 20 21 47 2 24 21 18 19 56 45 - 62 0 0 21 59 24 4 22 58 36 174 -45 22 18 5 21 40 51 24 14 50 19 50 45 - 61 0 0 21 53 59 4 22 51 37 175 -45 22 12 39 21 35 27 24 9 12 19 45 31 - 60 0 0 21 49 22 4 22 44 37 177 -45 22 8 0 21 30 52 24 4 24 19 41 3 - 59 0 0 21 45 34 4 22 36 37 178 -45 22 4 11 21 27 4 24 0 27 19 37 22 - 58 0 0 21 42 33 4 22 29 37 179 -45 22 1 9 21 24 5 23 57 19 19 34 28 - 57 0 0 21 40 21 4 22 22 37 180 -45 21 58 56 21 21 53 23 55 2 19 32 20 - 56 0 0 21 38 56 4 22 15 37 181 -45 21 57 31 21 20 29 23 53 34 19 30 58 - 55 0 0 21 38 20 4 22 7 37 182 -45 21 56 55 21 19 53 23 52 56 19 30 23 - 54 0 0 21 38 32 4 22 0 37 183 -44 21 57 7 21 20 5 23 53 9 19 30 35 - 53 0 0 21 39 32 4 21 53 37 184 -44 21 58 7 21 21 5 23 54 11 19 31 33 - 52 0 0 21 41 20 4 21 46 37 185 -44 21 59 56 21 22 52 23 56 4 19 33 17 - 51 0 0 21 43 56 4 21 38 37 186 -44 22 2 33 21 25 28 23 58 46 19 35 48 - 50 0 0 21 47 21 4 21 31 36 187 -43 22 5 58 21 28 51 24 2 19 19 39 5 - 49 0 0 21 51 33 4 21 24 36 188 -43 22 10 12 21 33 2 24 6 41 19 43 9 - 48 0 0 21 56 34 4 21 17 36 189 -43 22 15 15 21 38 2 24 11 54 19 48 0 - 47 0 0 22 2 23 4 21 10 36 190 -42 22 21 6 21 43 49 24 17 57 19 53 37 - 46 0 0 22 9 0 4 21 3 36 191 -42 22 27 45 21 50 24 24 24 51 20 0 0 - 45 0 0 22 16 26 4 20 56 35 192 -41 22 35 13 21 57 48 24 32 34 20 7 11 - 44 0 0 22 24 40 4 20 49 35 193 -41 22 43 30 22 5 59 24 41 9 20 15 8 - 43 0 0 22 33 43 4 20 42 35 194 -40 22 52 36 22 14 59 24 50 33 20 23 52 - 42 0 0 22 43 35 4 20 35 34 195 -40 23 2 30 22 24 47 25 0 49 20 33 23 - 41 0 0 22 54 15 4 20 28 34 196 -39 23 13 14 22 35 24 25 11 55 20 43 41 - 40 0 0 23 5 44 4 20 21 33 196 -39 23 24 46 22 46 49 25 23 52 20 54 46 - 39 0 0 23 18 1 4 20 14 33 197 -38 23 37 8 22 59 3 25 36 40 21 6 37 - 38 0 0 23 31 8 4 20 8 32 198 -37 23 50 19 23 12 6 25 50 19 21 19 17 - 37 0 0 23 45 4 4 20 1 32 199 -37 24 4 19 23 25 57 26 4 50 21 32 43 - 36 0 0 23 59 49 4 19 55 31 200 -36 24 19 9 23 40 37 26 20 12 21 46 57 - 35 0 0 24 15 23 4 19 48 31 201 -35 24 34 49 23 56 7 26 36 25 22 1 58 - 34 0 0 24 31 47 4 19 42 30 202 -35 24 51 18 24 12 25 26 53 31 22 17 46 - 33 0 0 24 49 0 4 19 36 30 203 -34 25 8 37 24 29 33 27 11 28 22 34 22 - 32 0 0 25 7 3 4 19 29 29 203 -33 25 26 45 24 47 30 27 30 17 22 51 46 - 31 0 0 25 25 55 4 19 23 28 204 -32 25 45 44 25 6 16 27 49 58 23 9 57 - 30 0 0 25 45 37 4 19 18 28 205 -32 26 5 33 25 25 52 28 10 32 23 28 57 - 29 0 0 26 6 10 4 19 12 27 206 -31 26 26 12 25 46 17 28 31 58 23 48 44 - 28 0 0 26 27 32 4 19 6 26 206 -30 26 47 42 26 7 32 28 54 17 24 9 18 - 27 0 0 26 49 44 4 19 0 26 207 -29 27 10 2 26 29 36 29 17 29 24 30 41 - 26 0 0 27 12 46 4 18 55 25 208 -28 27 33 12 26 52 31 29 41 33 24 52 52 - 25 0 0 27 36 39 4 18 50 24 209 -27 27 57 13 27 16 15 30 6 31 25 15 50 - 24 0 0 28 1 22 4 18 45 23 209 -26 28 22 5 27 40 49 30 32 21 25 39 37 - 23 0 0 28 26 55 4 18 40 23 210 -26 28 47 47 28 6 14 30 59 6 26 4 11 - 22 0 0 28 53 18 4 18 35 22 211 -25 29 14 20 28 32 28 31 26 43 26 29 33 - 21 0 0 29 20 32 4 18 30 21 211 -24 29 41 43 28 59 31 31 55 14 26 55 44 - 20 0 0 29 48 35 4 18 25 20 212 -23 30 9 58 29 27 25 32 24 38 27 22 42 - 19 0 0 30 17 30 4 18 21 19 213 -22 30 39 3 29 56 9 32 54 57 27 50 27 - 18 0 0 30 47 14 4 18 17 18 213 -21 31 8 58 30 25 42 33 26 8 28 19 0 - 17 0 0 31 17 48 4 18 13 17 214 -20 31 39 44 30 56 5 33 58 14 28 48 21 - 16 0 0 31 49 13 4 18 9 17 215 -19 32 11 21 31 27 18 34 31 13 29 18 29 - 15 0 0 32 21 27 4 18 5 16 215 -18 32 43 47 31 59 20 35 5 5 29 49 24 - 14 0 0 32 54 30 4 18 2 15 216 -17 33 17 4 32 32 11 35 39 52 30 21 6 - 13 0 0 33 28 24 4 17 58 14 216 -16 33 51 11 33 5 51 36 15 31 30 53 34 - 12 0 0 34 3 6 4 17 55 13 217 -15 34 26 7 33 40 20 36 52 4 31 26 48 - 11 0 0 34 38 37 4 17 52 12 218 -14 35 1 52 34 15 36 37 29 29 32 0 49 - 10 0 0 35 14 56 4 17 50 11 218 -13 35 38 27 34 51 41 38 7 48 32 35 34 - 9 0 0 35 52 3 4 17 47 10 219 -12 36 15 49 35 28 33 38 46 59 33 11 5 - 8 0 0 36 29 58 4 17 45 9 220 -11 36 54 0 36 6 12 39 27 2 33 47 20 - 7 0 0 37 8 39 4 17 43 8 220 -10 37 32 58 36 44 38 40 7 56 34 24 18 - 6 0 0 37 48 7 4 17 41 7 221 -9 38 12 43 37 23 49 40 49 42 .. .. .. - 5 0 0 38 28 20 4 17 40 6 221 -8 38 53 14 38 3 45 41 32 18 .. .. .. - 4 0 0 39 9 18 4 17 39 5 222 -7 39 34 30 38 44 25 42 15 44 .. .. .. - 3 0 0 39 51 0 4 17 38 4 223 -6 40 16 31 39 25 49 42 59 59 .. .. .. - 2 0 0 40 33 25 4 17 37 3 223 -5 40 59 15 40 7 55 43 45 3 .. .. .. - 1 0 0 41 16 31 4 17 36 2 224 -4 41 42 42 40 50 42 .. .. .. .. .. .. 0 0 0 42 0 18 4 17 36 1 225 -3 42 26 50 41 34 9 .. .. .. .. .. .. Uncertainty in time = +/- 9 secs Prediction of 2009 Jun 30.0 Data for the target star ------------------------ * name: UCAC2 18789908 * constellation : Sagittarius * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 19 24 29.0255 DE: -31 29 46.276 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .047, .058 ) * V mag [mag]: 11.7 * B mag [mag]: 0.0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (2137) Priscilla approx. diameter [km]: 41 approx. diameter ["]: .024 distance from Earth [AU]: 2.36900 * orbital information: orbit source: Preston date of fit: 2009 Jun 30 source of used astrometry: FASTT TMO MPC (via Astdys) number of used observations: 737 number of rejected observations: 23 time covered by the observations: 1936 Aug 24 - 2009 Jun 24 1 sigma uncertainty ellipse (major, minor, PA): 0.059, 0.045, 71° remarks: * orbital elements for (2137) Priscilla : Mean anomaly = 191.79061924 deg Arg. of pericenter = 135.21117662 deg Long. of node = 320.09582808 deg Inclination = 11.71559565 deg Eccentricity = 0.05993496 Semimajor axis = 3.18526051 AU Perihelion dist = 2.99435207 AU Mag: H = 11.01, G = 0.15 Epoch of elements : MJD 55016.18300000 TDT (2009 Jul 04.183) ------ occelmnt file for Occult BEGIN ----------------------------------- 2009 Jul 4 2137 Priscilla 4h 22.2m UT 11.7 19 24 29.025-31 29 46.28UCAC2 18789908 0.0 15.9 41 3.0 2.369 -2.262 0.48 -56.7517 -31.495 115.55 22.87 4.3703 0.01295 0.79813 -7.79435 0.12855 -0.00069 0.00083 2000 190.7186412009 628.00000135.211177320.095828 11.7155960.05993496 3.1852605 2.994352011.1 5.00.15 RATE 1.7337510 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.075 0.073 78 4.04 0.072 0 55012.0020090704_789908 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2009 Jun 30, 15:44 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org