IOTA/IOTA-ES occultation update for (155) Scylla / TYC 7466-00511-1 event on 2007 Aug 02, 05:09 UT Visible from USA, Mexico Summary ------- On 2007 Aug 02 UT, the 49 km diameter asteroid (155) Scylla will occult a 9.6 mag star in the constellation Microscopium for observers along a path across USA, Mexico. In the case of an occultation, the combined light of the asteroid and the star will drop by 6.4 mag to 16.0 mag (the magnitude of the asteroid) for at most 3.4 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: 64 * date and approx. time of event: 2007 Aug 02, 05:05 - 2007 Aug 02, 05:13 UT * midpoint of event [JD]: 2454314.71484167 * magnitude of target star: 9.6 * magnitude drop [mag]: 6.4 * estimated maximum duration [s]: 3.4 * Moon: 87 % sunlit, 47° distance * Sun: 163° distance * rough path description: USA, Mexico The occultation path -------------------- * approximate projected width [km]: 96 * 1 sigma uncertainty interval [path widths]: +/- 0.94 * 1 sigma uncertainty interval [seconds]: +/- 3.7 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .040 +/- .029) * 1 sigma uncertainty ellipse (major, minor, PA): ( .040", .028", 79° ) * approx speed of asteroid's shadow [km/s]: 14.5738 * website for maps: http://lunar-occultations.com/iota/asteroids/astrndx.htm http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 7466-00511-1 by 155 Scylla on 2007 Aug 02 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 ... .. .. 54 0 0 .. .. .. .. .. .. ... .. .. ... .. .. - 52 5 29 ... .. .. - 50 20 16 53 0 0 5 5 41 1 198 -16 - 51 7 4 - 49 34 0 - 52 36 29 ... .. .. - 50 55 17 52 0 0 5 5 42 2 197 -17 - 51 41 26 - 50 9 39 - 53 9 38 ... .. .. - 51 32 10 51 0 0 5 5 42 3 197 -18 - 52 17 45 - 50 47 6 - 53 44 53 ... .. .. - 52 10 54 50 0 0 5 5 43 4 196 -19 - 52 55 59 - 51 26 20 - 54 22 11 ... .. .. - 52 51 29 49 0 0 5 5 45 5 196 -20 - 53 36 8 - 52 7 21 - 55 1 32 ... .. .. - 53 33 55 48 0 0 5 5 46 6 195 -22 - 54 18 12 - 52 50 8 - 55 42 56 ... .. .. - 54 18 13 47 0 0 5 5 48 7 195 -23 - 55 2 12 - 53 34 44 - 56 26 24 - 52 14 18 - 55 4 23 46 0 0 5 5 51 8 194 -24 - 55 48 9 - 54 21 9 - 57 11 57 - 53 1 11 - 55 52 30 45 0 0 5 5 53 10 193 -25 - 56 36 6 - 55 9 26 - 57 59 37 - 53 49 49 - 56 42 35 44 0 0 5 5 56 11 193 -26 - 57 26 6 - 55 59 37 - 58 49 29 - 54 40 13 - 57 34 42 43 0 0 5 6 0 12 192 -27 - 58 18 12 - 56 51 46 - 59 41 35 - 55 32 29 - 58 28 57 42 0 0 5 6 3 13 191 -28 - 59 12 30 - 57 45 59 - 60 36 2 - 56 26 41 - 59 25 24 41 0 0 5 6 8 14 191 -30 - 60 9 5 - 58 42 20 - 61 32 56 - 57 22 53 - 60 24 11 40 0 0 5 6 12 15 190 -31 - 61 8 4 - 59 40 55 - 62 32 24 - 58 21 11 - 61 25 25 39 0 0 5 6 17 16 189 -32 - 62 9 37 - 60 41 53 - 63 34 37 - 59 21 42 - 62 29 16 38 0 0 5 6 23 17 188 -33 - 63 13 52 - 61 45 22 - 64 39 44 - 60 24 35 - 63 35 55 37 0 0 5 6 29 18 187 -34 - 64 21 2 - 62 51 33 - 65 48 0 - 61 29 59 - 64 45 35 36 0 0 5 6 36 20 186 -35 - 65 31 20 - 64 0 38 - 66 59 40 - 62 38 5 - 65 58 33 35 0 0 5 6 43 21 185 -37 - 66 45 5 - 65 12 52 - 68 15 4 - 63 49 6 - 67 15 6 34 0 0 5 6 50 22 184 -38 - 68 2 36 - 66 28 33 - 69 34 37 - 65 3 19 - 68 35 39 33 0 0 5 6 59 23 183 -39 - 69 24 18 - 67 48 2 - 70 58 47 - 66 21 1 - 70 0 40 32 0 0 5 7 8 24 182 -40 - 70 50 43 - 69 11 46 - 72 28 12 - 67 42 36 - 71 30 44 31 0 0 5 7 18 25 181 -41 - 72 22 29 - 70 40 16 - 74 3 39 - 69 8 31 - 73 6 38 30 0 0 5 7 29 26 179 -42 - 74 0 29 - 72 14 15 - 75 46 14 - 70 39 21 - 74 49 19 29 0 0 5 7 40 27 178 -43 - 75 45 47 - 73 54 35 - 77 37 20 - 72 15 48 - 76 40 9 28 0 0 5 7 53 28 176 -44 - 77 39 58 - 75 42 26 - 79 39 3 - 73 58 50 - 78 41 0 27 0 0 5 8 7 29 174 -45 - 79 45 12 - 77 39 25 - 81 54 26 - 75 49 42 Latitude Latitude Latitude Latitude - 80 0 0 26 23 44 5 8 17 29 173 -46 26 53 18 25 54 39 27 50 15 25 1 11 - 81 0 0 25 57 44 5 8 24 29 172 -46 26 26 58 25 28 57 27 23 17 24 36 0 - 82 0 0 25 33 1 5 8 31 30 171 -46 26 1 58 25 4 31 26 57 41 24 12 4 - 83 0 0 25 9 35 5 8 38 30 170 -46 25 38 15 24 41 21 26 33 25 23 49 21 - 84 0 0 24 47 25 5 8 45 30 169 -47 25 15 50 24 19 25 26 10 29 23 27 52 - 85 0 0 24 26 29 5 8 52 30 168 -47 24 54 40 23 58 43 25 48 51 23 7 34 - 86 0 0 24 6 48 5 9 0 30 167 -47 24 34 45 23 39 14 25 28 29 22 48 27 - 87 0 0 23 48 19 5 9 7 30 166 -47 24 16 5 23 20 57 25 9 24 22 30 31 - 88 0 0 23 31 3 5 9 14 31 165 -47 23 58 38 23 3 52 24 51 35 22 13 45 - 89 0 0 23 14 59 5 9 21 31 164 -47 23 42 23 22 47 58 24 34 59 21 58 8 - 90 0 0 23 0 6 5 9 28 31 164 -47 23 27 20 22 33 14 24 19 38 21 43 40 - 91 0 0 22 46 23 5 9 35 30 163 -47 23 13 29 22 19 39 24 5 30 21 30 20 - 92 0 0 22 33 51 5 9 42 30 162 -47 23 0 49 22 7 14 23 52 34 21 18 8 - 93 0 0 22 22 27 5 9 49 30 161 -47 22 49 19 21 55 57 23 40 50 21 7 3 - 94 0 0 22 12 14 5 9 56 30 160 -46 22 38 59 21 45 50 23 30 18 20 57 6 - 95 0 0 22 3 9 5 10 3 30 159 -46 22 29 48 21 36 50 23 20 57 20 48 15 - 96 0 0 21 55 12 5 10 10 30 158 -46 22 21 47 21 28 58 23 12 46 20 40 31 - 97 0 0 21 48 24 5 10 16 30 157 -45 22 14 55 21 22 13 23 5 46 20 33 53 - 98 0 0 21 42 44 5 10 23 29 156 -45 22 9 12 21 16 36 22 59 56 20 28 22 - 99 0 0 21 38 11 5 10 30 29 156 -45 22 4 37 21 12 6 22 55 17 20 23 56 -100 0 0 21 34 47 5 10 36 29 155 -44 22 1 11 21 8 44 22 51 47 20 20 36 -101 0 0 21 32 30 5 10 43 28 154 -44 21 58 53 21 6 28 22 49 27 20 18 22 -102 0 0 21 31 21 5 10 49 28 153 -43 21 57 44 21 5 19 22 48 17 20 17 14 -103 0 0 21 31 20 5 10 56 27 152 -43 21 57 43 21 5 18 22 48 17 20 17 12 -104 0 0 21 32 27 5 11 2 27 152 -42 21 58 50 21 6 23 22 49 26 20 18 16 -105 0 0 21 34 41 5 11 8 27 151 -42 22 1 7 21 8 36 22 51 46 20 20 26 -106 0 0 21 38 4 5 11 14 26 150 -41 22 4 32 21 11 56 22 55 16 20 23 42 -107 0 0 21 42 35 5 11 20 26 149 -40 22 9 6 21 16 24 22 59 56 20 28 5 -108 0 0 21 48 14 5 11 26 25 149 -40 22 14 49 21 22 0 23 5 47 20 33 34 -109 0 0 21 55 3 5 11 32 24 148 -39 22 21 42 21 28 44 23 12 50 20 40 10 -110 0 0 22 3 0 5 11 37 24 147 -38 22 29 45 21 36 37 23 21 3 20 47 53 -111 0 0 22 12 8 5 11 43 23 147 -38 22 38 59 21 45 38 23 30 29 20 56 44 -112 0 0 22 22 25 5 11 48 23 146 -37 22 49 23 21 55 49 23 41 7 21 6 43 -113 0 0 22 33 53 5 11 53 22 145 -36 23 0 59 22 7 10 23 52 59 21 17 51 -114 0 0 22 46 33 5 11 58 21 145 -35 23 13 47 22 19 41 24 6 4 21 30 7 -115 0 0 23 0 24 5 12 3 21 144 -34 23 27 47 22 33 23 24 20 23 21 43 33 -116 0 0 23 15 27 5 12 8 20 144 -34 23 43 1 22 48 16 24 35 58 21 58 9 -117 0 0 23 31 44 5 12 13 19 143 -33 23 59 29 23 4 22 24 52 48 22 13 56 -118 0 0 23 49 15 5 12 17 18 142 -32 24 17 13 23 21 42 25 10 56 22 30 55 -119 0 0 24 8 1 5 12 22 17 142 -31 24 36 12 23 40 15 25 30 22 22 49 5 -120 0 0 24 28 3 5 12 26 17 141 -30 24 56 28 24 0 3 25 51 7 23 8 29 -121 0 0 24 49 21 5 12 30 16 141 -29 25 18 2 24 21 7 26 13 12 23 29 7 -122 0 0 25 11 58 5 12 34 15 140 -28 25 40 55 24 43 27 26 36 39 23 51 0 -123 0 0 25 35 54 5 12 38 14 140 -27 26 5 9 25 7 6 27 1 29 24 14 8 -124 0 0 26 1 10 5 12 41 13 139 -26 26 30 44 25 32 4 27 27 43 24 38 34 -125 0 0 26 27 48 5 12 44 12 139 -25 26 57 43 25 58 22 27 55 23 25 4 18 -126 0 0 26 55 49 5 12 47 11 138 -25 27 26 6 26 26 2 28 24 32 25 31 21 -127 0 0 27 25 15 5 12 50 10 138 -24 27 55 56 26 55 6 28 55 10 25 59 44 -128 0 0 27 56 7 5 12 53 9 137 -22 28 27 14 27 25 34 29 27 20 26 29 30 -129 0 0 28 28 28 5 12 55 8 137 -21 29 0 2 27 57 29 30 1 4 27 0 40 -130 0 0 29 2 19 5 12 57 7 136 -20 29 34 23 28 30 52 30 36 25 27 33 14 -131 0 0 29 37 43 5 12 59 6 136 -19 30 10 18 29 5 45 31 13 25 28 7 16 -132 0 0 30 14 41 5 13 1 5 135 -18 30 47 50 29 42 11 31 52 8 .. .. .. -133 0 0 30 53 16 5 13 2 4 135 -17 31 27 2 30 20 12 32 32 36 .. .. .. -134 0 0 31 33 31 5 13 3 3 134 -16 32 7 57 30 59 50 33 14 53 .. .. .. -135 0 0 32 15 29 5 13 4 2 133 -15 32 50 37 31 41 8 33 59 3 .. .. .. -136 0 0 32 59 13 5 13 4 1 133 -14 33 35 8 .. .. .. .. .. .. .. .. .. Data for the target star ------------------------ * name: TYC 7466-00511-1 * constellation : Microscopium * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 20 59 27.1401 DE: -34 19 02.042 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .025, .019 ) * V mag [mag]: 9.6 * B mag [mag]: 9.8 * Apparent position with proper motion RA(deg): 314.9905702900 DE(deg): -34.2869328443 * Equation of equinoxes (radians) : 0.000033063793876 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (155) Scylla approx. diameter [km]: 49 approx. diameter ["]: .030 distance from Earth [AU]: 2.23100 * orbital information: orbit source: Preston date of fit: 2007 Jul 01 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 571 number of rejected observations: 26 time covered by the observations: 1907 Nov 02 - 2007 May 23 1 sigma uncertainty ellipse (major, minor, PA): 0.032, 0.021, 73° remarks: * orbital elements for (155) Scylla : Mean anomaly = 245.54478655 deg Arg. of pericenter = 46.02118639 deg Long. of node = 41.05174600 deg Inclination = 11.39059153 deg Eccentricity = 0.27658195 Semimajor axis = 2.75673570 AU Perihelion dist = 1.99427236 AU Mag: H = 11.05, G = 0.15 Epoch of elements : MJD 54314.21500000 TDT (2007 Aug 02.215) ------ occelmnt file for Occult BEGIN ----------------------------------- 2007 Aug 02 155 Scylla 5h 9.4m UT 9.6 20 59 27.140-34 19 2.04TYC 7466-00511-1 9.8 16.0 49 3.4 2.231 -2.495 -9.79 287.097 -34.314 104.24 17.86 5.1562 -.25997 .82039 -7.84132 -2.48565 -0.00030 0.00158 2000 244.6371562007 729.00000 46.021186 41.051746 11.3905920.276581952.756735701.9942723611.35 0.15 RATE 2.1533340 .0000000 .0000000 .0000000 .00000000 .00000000 .00000000 Meas 0.040 0.028 79.4 1.940 0.028 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2007 Jul 08, 23:01 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org