IOTA/IOTA-ES occultation update for (5917) 1991 NG / 2UCAC 32802314 event on 2008 Jul 02, 18:22 UT Visible from New Guinea Summary ------- On 2008 Jul 02 UT, the 18 km diameter asteroid (5917) 1991 NG will occult a 10.4 mag star in the constellation Pegasus for observers along a path across New Guinea. In the case of an occultation, the combined light of the asteroid and the star will drop by 4.6 mag to 15.0 mag (the magnitude of the asteroid) for at most 2.2 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: 11 * date and approx. time of event: 2008 Jul 02, 18:10 - 2008 Jul 02, 18:30 UT * midpoint of event [JD]: 2454650.26556667 * magnitude of target star: 10.4 * magnitude drop [mag]: 4.6 * estimated maximum duration [s]: 2.2 * Moon: 0 % sunlit, 120° distance * Sun: 125° distance * rough path description: New Guinea The occultation path -------------------- * approximate projected width [km]: 19 * 1 sigma uncertainty interval [path widths]: +/- 6.27 * 1 sigma uncertainty interval [seconds]: +/- 9.7 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .105 +/- .076) * 1 sigma uncertainty ellipse (major, minor, PA): ( .112", .065", 64° ) * approx speed of asteroid's shadow [km/s]: 8.1858 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of 2UCAC 32802314 by 5917 1991 NG on 2008 Jul 2 Centre Star Star Sun Path Limit1 Path Limit2 Error Limit1 Error Limit2 E. Longitude Latitude U.T. Alt Az Alt o ' " o ' " h m s o o o o ' " o ' " o ' " o ' " o ' " o ' " o ' " o ' " Longitude Latitude Longitude Latitude Longitude Latitude Longitude Latitude -167 51 1 -66 15 48 18 10 11 11 305 -16 -168 11 9 -66 15 46 -167 30 40 -66 15 51 -172 9 20 -66 16 13 -162 55 17 -66 17 38 -177 11 40 -62 28 57 18 10 30 17 313 -18 -177 25 51 -62 29 8 -176 57 25 -62 28 46 179 41 9 -62 31 52 -173 52 55 -62 26 52 177 23 51 -59 15 50 18 10 49 21 318 -20 177 12 5 -59 16 5 177 35 40 -59 15 35 174 47 7 -59 19 28 -179 53 14 -59 12 44 173 40 44 -56 23 9 18 11 8 24 321 -21 173 30 21 -56 23 25 173 51 7 -56 22 52 171 22 1 -56 27 1 176 3 27 -56 19 39 170 53 41 -53 44 47 18 11 27 27 323 -22 170 44 15 -53 45 4 171 3 8 -53 44 30 168 47 17 -53 48 45 173 2 59 -53 41 7 168 41 54 -51 17 16 18 11 46 30 324 -23 168 33 10 -51 17 33 168 50 39 -51 16 59 166 44 35 -51 21 15 170 41 28 -51 13 32 166 54 8 -48 58 18 18 12 4 33 325 -24 166 45 56 -48 58 35 167 2 21 -48 58 0 165 3 52 -49 2 15 168 46 13 -48 54 33 165 23 39 -46 46 18 18 12 23 35 326 -25 165 15 52 -46 46 35 165 31 26 -46 46 1 163 39 3 -46 50 14 167 9 45 -46 42 34 164 6 7 -44 40 8 18 12 42 37 327 -25 163 58 42 -44 40 25 164 13 33 -44 39 51 162 26 12 -44 44 1 165 47 20 -44 36 25 162 58 37 -42 38 54 18 13 1 39 327 -26 162 51 29 -42 39 10 163 5 45 -42 38 37 161 22 38 -42 42 44 164 35 43 -42 35 13 161 59 4 -40 41 55 18 13 20 41 327 -26 161 52 11 -40 42 11 162 5 57 -40 41 38 160 26 27 -40 45 43 163 32 41 -40 38 16 161 5 58 -38 48 38 18 13 38 43 327 -27 160 59 19 -38 48 54 161 12 38 -38 48 21 159 36 16 -38 52 23 162 36 35 -38 45 0 160 18 12 -36 58 35 18 13 57 45 327 -27 160 11 44 -36 58 52 160 24 40 -36 58 19 158 51 1 -37 2 18 161 46 12 -36 55 0 159 34 53 -35 11 25 18 14 16 47 327 -27 159 28 35 -35 11 41 159 41 11 -35 11 9 158 9 56 -35 15 6 161 0 35 -35 7 52 158 55 20 -33 26 49 18 14 35 49 327 -27 158 49 11 -33 27 5 159 1 29 -33 26 33 157 32 22 -33 30 27 160 19 0 -33 23 18 158 19 2 -31 44 30 18 14 54 50 326 -27 158 13 1 -31 44 45 158 25 3 -31 44 14 156 57 50 -31 48 6 159 40 54 -31 41 0 157 45 32 -30 4 14 18 15 12 52 326 -27 157 39 38 -30 4 30 157 51 27 -30 3 58 156 25 54 -30 7 48 159 5 47 -30 0 46 157 14 30 -28 25 49 18 15 31 54 325 -27 157 8 42 -28 26 5 157 20 18 -28 25 34 155 56 17 -28 29 21 158 33 18 -28 22 23 156 45 37 -26 49 6 18 15 50 55 325 -27 156 39 55 -26 49 21 156 51 19 -26 48 50 155 28 40 -26 52 36 158 3 7 -26 45 41 156 18 40 -25 13 53 18 16 9 57 324 -27 156 13 3 -25 14 8 156 24 17 -25 13 38 155 2 51 -25 17 21 157 35 0 -25 10 30 155 53 25 -23 40 3 18 16 28 58 323 -27 155 47 53 -23 40 18 155 58 57 -23 39 48 154 38 38 -23 43 30 157 8 42 -23 36 41 155 29 43 -22 7 28 18 16 46 59 322 -27 155 24 15 -22 7 43 155 35 11 -22 7 13 154 15 52 -22 10 54 156 44 3 -22 4 8 155 7 25 -20 36 2 18 17 5 61 321 -27 155 2 0 -20 36 17 155 12 49 -20 35 47 153 54 24 -20 39 26 156 20 53 -20 32 42 154 46 23 -19 5 38 18 17 24 62 319 -27 154 41 2 -19 5 52 154 51 44 -19 5 23 153 34 8 -19 9 1 155 59 5 -19 2 19 154 26 31 -17 36 10 18 17 43 63 318 -27 154 21 13 -17 36 25 154 31 49 -17 35 55 153 14 57 -17 39 32 155 38 32 -17 32 52 154 7 43 -16 7 33 18 18 2 65 316 -26 154 2 28 -16 7 48 154 12 59 -16 7 19 152 56 45 -16 10 55 155 19 7 -16 4 17 153 49 55 -14 39 43 18 18 20 66 314 -26 153 44 42 -14 39 58 153 55 8 -14 39 29 152 39 30 -14 43 4 155 0 45 -14 36 27 153 33 1 -13 12 35 18 18 39 67 312 -26 153 27 51 -13 12 49 153 38 12 -13 12 20 152 23 5 -13 15 55 154 43 22 -13 9 20 153 17 0 -11 46 4 18 18 58 68 310 -26 153 11 51 -11 46 19 153 22 9 -11 45 50 152 7 29 -11 49 23 154 26 54 -11 42 49 153 1 46 -10 20 7 18 19 17 69 307 -25 152 56 39 -10 20 21 153 6 53 -10 19 52 151 52 38 -10 23 26 154 11 18 -10 16 53 152 47 18 - 8 54 40 18 19 36 70 305 -25 152 42 12 - 8 54 54 152 52 24 - 8 54 25 151 38 29 - 8 57 58 153 56 31 - 8 51 26 152 33 33 - 7 29 39 18 19 54 71 302 -25 152 28 29 - 7 29 53 152 38 38 - 7 29 24 151 25 0 - 7 32 56 153 42 29 - 7 26 25 152 20 29 - 6 5 0 18 20 13 72 298 -24 152 15 26 - 6 5 15 152 25 33 - 6 4 46 151 12 9 - 6 8 18 153 29 12 - 6 1 47 152 8 4 - 4 40 41 18 20 32 72 295 -24 152 3 1 - 4 40 56 152 13 7 - 4 40 27 150 59 55 - 4 43 59 153 16 36 - 4 37 28 151 56 17 - 3 16 39 18 20 51 73 291 -23 151 51 15 - 3 16 53 152 1 19 - 3 16 24 150 48 16 - 3 19 56 153 4 41 - 3 13 26 151 45 6 - 1 52 50 18 21 10 74 286 -23 151 40 4 - 1 53 4 151 50 8 - 1 52 35 150 37 10 - 1 56 7 152 53 24 - 1 49 36 151 34 30 - 0 29 10 18 21 29 74 282 -22 151 29 28 - 0 29 25 151 39 31 - 0 28 56 150 26 36 - 0 32 28 152 42 45 - 0 25 57 151 24 28 0 54 22 18 21 47 74 277 -22 151 19 26 0 54 7 151 29 29 0 54 36 150 16 35 0 51 4 152 32 44 0 57 35 151 14 59 2 17 49 18 22 6 75 272 -21 151 9 58 2 17 35 151 20 1 2 18 4 150 7 4 2 14 32 152 23 18 2 21 3 151 6 4 3 41 15 18 22 25 75 267 -21 151 1 2 3 41 1 151 11 6 3 41 30 149 58 3 3 37 57 152 14 27 3 44 29 150 57 41 5 4 43 18 22 44 75 262 -20 150 52 38 5 4 29 151 2 44 5 4 58 149 49 33 5 1 25 152 6 12 5 7 57 150 49 51 6 28 15 18 23 3 74 257 -20 150 44 47 6 28 1 150 54 54 6 28 30 149 41 32 6 24 57 151 58 32 6 31 30 150 42 33 7 51 55 18 23 21 74 252 -19 150 37 28 7 51 40 150 47 37 7 52 9 149 34 2 7 48 36 151 51 28 7 55 10 150 35 48 9 15 45 18 23 40 74 248 -18 150 30 42 9 15 30 150 40 53 9 15 59 149 27 1 9 12 25 151 44 58 9 19 0 150 29 35 10 39 48 18 23 59 73 244 -18 150 24 28 10 39 33 150 34 42 10 40 3 149 20 30 10 36 27 151 39 5 10 43 4 150 23 57 12 4 7 18 24 18 72 240 -17 150 18 48 12 3 53 150 29 5 12 4 22 149 14 30 12 0 46 151 33 47 12 7 25 150 18 52 13 28 47 18 24 37 72 236 -16 150 13 42 13 28 32 150 24 3 13 29 2 149 9 1 13 25 24 151 29 8 13 32 5 150 14 23 14 53 49 18 24 55 71 233 -16 150 9 11 14 53 34 150 19 35 14 54 4 149 4 5 14 50 25 151 25 7 14 57 8 150 10 30 16 19 17 18 25 14 70 230 -15 150 5 16 16 19 2 150 15 45 16 19 32 148 59 41 16 15 53 151 21 45 16 22 38 150 7 16 17 45 16 18 25 33 69 227 -14 150 1 58 17 45 1 150 12 33 17 45 31 148 55 52 17 41 50 151 19 6 17 48 37 150 4 41 19 11 48 18 25 52 68 224 -13 149 59 21 19 11 33 150 10 1 19 12 3 148 52 40 19 8 21 151 17 9 19 15 11 150 2 48 20 38 58 18 26 11 67 222 -13 149 57 25 20 38 43 150 8 11 20 39 13 148 50 5 20 35 29 151 15 59 20 42 22 150 1 39 22 6 50 18 26 29 66 220 -12 149 56 13 22 6 34 150 7 6 22 7 5 148 48 10 22 3 20 151 15 38 22 10 15 150 1 18 23 35 28 18 26 48 64 218 -11 149 55 48 23 35 13 150 6 49 23 35 44 148 46 58 23 31 56 151 16 9 23 38 55 150 1 48 25 4 58 18 27 7 63 216 -10 149 56 13 25 4 42 150 7 23 25 5 13 148 46 32 25 1 24 151 17 36 25 8 26 150 3 12 26 35 24 18 27 26 62 215 -9 149 57 33 26 35 8 150 8 52 26 35 39 148 46 55 26 31 48 151 20 3 26 38 54 150 5 36 28 6 52 18 27 45 61 214 -9 149 59 52 28 6 36 150 11 21 28 7 8 148 48 11 28 3 14 151 23 36 28 10 25 150 9 6 29 39 29 18 28 3 59 212 -8 150 3 16 29 39 12 150 14 56 29 39 45 148 50 26 29 35 48 151 28 21 29 43 4 150 13 47 31 13 20 18 28 22 58 211 -7 150 7 51 31 13 4 150 19 43 31 13 37 148 53 46 31 9 38 151 34 26 31 16 58 150 19 48 32 48 35 18 28 41 56 210 -6 150 13 45 32 48 18 150 25 51 32 48 51 148 58 17 32 44 49 151 41 59 32 52 15 150 27 18 34 25 20 18 29 0 55 210 -5 150 21 8 34 25 4 150 33 28 34 25 37 149 4 8 34 21 32 151 51 10 34 29 3 150 36 28 36 3 46 18 29 19 53 209 -4 150 30 10 36 3 29 150 42 47 36 4 3 149 11 28 35 59 54 152 2 14 36 7 32 150 47 33 37 44 2 18 29 38 52 208 -3 150 41 6 37 43 45 150 54 1 37 44 19 149 20 31 37 40 7 152 15 24 37 47 51 151 0 49 39 26 21 18 29 56 50 208 -2 150 54 11 39 26 4 151 7 26 39 26 39 149 31 30 39 22 22 152 30 59 39 30 14 151 16 36 41 10 57 18 30 15 49 207 0 151 9 47 41 10 39 151 23 25 41 11 14 149 44 44 41 6 54 152 49 24 41 14 53 Uncertainty in time = +/- 15 secs [Prediction of 2008 May 22.0] Data for the target star ------------------------ * name: 2UCAC 32802314 * constellation : Pegasus * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 22 09 22.0701 DE: +02 44 09.015 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .038, .026 ) * V mag [mag]: 10.4 * B mag [mag]: 0.0 * Apparent position with proper motion RA(deg): 332.4560399239 DE(deg): 2.7782799326 * Equation of equinoxes (radians) : 0.000050327077168 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (5917) 1991 NG approx. diameter [km]: 18 approx. diameter ["]: .017 distance from Earth [AU]: 1.49000 * orbital information: orbit source: Preston date of fit: 2008 May 22 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 535 number of rejected observations: 9 time covered by the observations: 1952 Feb 01 - 2007 Aug 09 1 sigma uncertainty ellipse (major, minor, PA): 0.106, 0.060, 61° remarks: * orbital elements for (5917) 1991 NG : Mean anomaly = 0.10752213 deg Arg. of pericenter = 38.01064738 deg Long. of node = 276.08103060 deg Inclination = 14.28396901 deg Eccentricity = 0.14001022 Semimajor axis = 2.59465741 AU Perihelion dist = 2.23137885 AU Mag: H = 12.11, G = 0.15 Epoch of elements : MJD 54649.76500000 TDT (2008 Jul 02.765) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 Jul 2 5917 1991 NG 18h 22.4m UT 10.4 22 9 22.070 2 44 9.022UCAC 32802314 0.0 15.0 18 2.2 1.490 -0.116 27.21 135.5776 2.728 -94.56 22.97 18.3736 0.26517 0.01718 -0.28972 4.61119 -0.00376 -0.00222 2000 357.8047222008 623.00000 38.010647276.081031 14.2839690.14001022 2.5946574 2.231378911.3 5.00.15 RATE 2.3582180 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.112 0.065 64 7.27 0.104 0 54608.5020080702_802314 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 May 26, 14:36 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org