IOTA/IOTA-ES occultation update for (17) Thetis / 2UCAC 22797210 event on 2008 Sep 02, 10:33 UT Visible from E Russia Summary ------- On 2008 Sep 02 UT, the 90 km diameter asteroid (17) Thetis will occult a 13.0 mag star in the constellation Sagittarius for observers along a path across E Russia. In the case of an occultation, the combined light of the asteroid and the star will drop by 0.2 mag to 11.3 mag (the magnitude of the asteroid) for at most 29.4 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: 86 * date and approx. time of event: 2008 Sep 02, 10:08 - 2008 Sep 02, 10:53 UT * magnitude of target star: 13.0 * magnitude drop [mag]: 0.2 * estimated maximum duration [s]: 29.4 * Moon: 8 % sunlit, 96° distance * Sun: 128° distance * rough path description: E Russia The occultation path -------------------- * approximate projected width [km]: 140 * 1 sigma uncertainty interval [path widths]: +/- 0.59 * 1 sigma uncertainty interval [seconds]: +/- 16.3 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .050 +/- .050) * 1 sigma uncertainty ellipse (major, minor, PA): ( .050", .050", 90° ) * approx speed of asteroid's shadow [km/s]: 3.0596 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of 2UCAC 22797210 by 17 Thetis on 2008 Sep 2 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 134 4 32 64 0 0 10 8 39 2 160 0 132 36 30 135 33 0 ... .. .. 137 18 1 134 57 42 63 0 0 10 8 42 3 161 -1 133 32 36 136 23 14 ... .. .. 138 4 47 135 50 5 62 0 0 10 8 45 4 162 -2 134 27 41 137 12 54 132 50 57 138 51 17 136 41 46 61 0 0 10 8 50 5 163 -2 135 21 52 138 2 7 133 48 5 139 37 34 137 32 52 60 0 0 10 8 56 6 164 -3 136 15 16 138 50 55 134 44 11 140 23 40 138 23 27 59 0 0 10 9 3 7 164 -4 137 7 58 139 39 23 135 39 24 141 9 38 139 13 35 58 0 0 10 9 11 8 165 -5 138 0 4 140 27 34 136 33 50 141 55 31 140 3 21 57 0 0 10 9 21 9 166 -5 138 51 39 141 15 31 137 27 34 142 41 21 140 52 49 56 0 0 10 9 31 10 167 -6 139 42 47 142 3 18 138 20 42 143 27 10 141 42 2 55 0 0 10 9 43 12 167 -7 140 33 33 142 50 58 139 13 19 144 13 0 142 31 3 54 0 0 10 9 57 13 168 -8 141 24 1 143 38 34 140 5 29 144 58 54 143 19 56 53 0 0 10 10 11 14 169 -9 142 14 14 144 26 7 140 57 17 145 44 54 144 8 44 52 0 0 10 10 27 15 170 -10 143 4 17 145 13 42 141 48 47 146 31 3 144 57 31 51 0 0 10 10 44 16 171 -11 143 54 11 146 1 20 142 40 3 147 17 21 145 46 18 50 0 0 10 11 2 17 171 -12 144 44 1 146 49 5 143 31 8 148 3 53 146 35 9 49 0 0 10 11 22 18 172 -13 145 33 50 147 36 59 144 22 6 148 50 40 147 24 7 48 0 0 10 11 43 19 173 -14 146 23 41 148 25 4 145 13 0 149 37 44 148 13 15 47 0 0 10 12 5 20 174 -15 147 13 37 149 13 24 146 3 55 150 25 9 149 2 35 46 0 0 10 12 29 21 175 -16 148 3 42 150 2 2 146 54 52 151 12 56 149 52 12 45 0 0 10 12 54 22 176 -17 148 53 59 150 51 0 147 45 57 152 1 9 150 42 9 44 0 0 10 13 20 23 177 -18 149 44 30 151 40 21 148 37 11 152 49 51 151 32 27 43 0 0 10 13 48 24 177 -19 150 35 21 152 30 10 149 28 40 153 39 4 152 23 12 42 0 0 10 14 17 25 178 -20 151 26 33 153 20 28 150 20 26 154 28 53 153 14 27 41 0 0 10 14 48 26 179 -21 152 18 11 154 11 21 151 12 33 155 19 21 154 6 15 40 0 0 10 15 20 27 180 -23 153 10 19 155 2 51 152 5 4 156 10 32 154 58 41 39 0 0 10 15 54 28 182 -24 154 3 0 155 55 3 152 58 6 157 2 30 155 51 50 38 0 0 10 16 29 29 183 -25 154 56 19 156 48 2 153 51 40 157 55 20 156 45 45 37 0 0 10 17 6 30 184 -26 155 50 22 157 41 53 154 45 52 158 49 7 157 40 33 36 0 0 10 17 44 31 185 -27 156 45 12 158 36 40 155 40 48 159 43 56 158 36 18 35 0 0 10 18 24 32 186 -29 157 40 55 159 32 30 156 36 31 160 39 54 159 33 8 34 0 0 10 19 5 33 188 -30 158 37 38 160 29 29 157 33 8 161 37 8 160 31 8 33 0 0 10 19 48 34 189 -31 159 35 26 161 27 44 158 30 45 162 35 45 161 30 27 32 0 0 10 20 33 35 190 -33 160 34 27 162 27 24 159 29 29 163 35 54 162 31 13 31 0 0 10 21 20 35 192 -34 161 34 49 163 28 37 160 29 27 164 37 45 163 33 36 30 0 0 10 22 9 36 193 -36 162 36 41 164 31 34 161 30 49 165 41 29 164 37 46 29 0 0 10 22 59 37 195 -37 163 40 14 165 36 27 162 33 42 166 47 19 165 43 56 28 0 0 10 23 51 38 197 -39 164 45 38 166 43 29 163 38 18 167 55 30 166 52 21 27 0 0 10 24 46 38 198 -40 165 53 7 167 52 56 164 44 49 169 6 20 168 3 17 26 0 0 10 25 43 39 200 -42 167 2 56 169 5 7 165 53 29 170 20 11 169 17 5 25 0 0 10 26 42 39 202 -44 168 15 25 170 20 23 167 4 34 171 37 27 170 34 8 24 0 0 10 27 44 39 204 -45 169 30 53 171 39 14 168 18 23 172 58 41 171 54 57 23 0 0 10 28 49 40 206 -47 170 49 48 173 2 10 169 35 19 174 24 32 173 20 7 22 0 0 10 29 56 40 208 -49 172 12 41 174 29 56 170 55 50 175 55 51 174 50 25 21 0 0 10 31 7 40 211 -51 173 40 12 176 3 26 172 20 30 177 33 45 176 26 52 20 0 0 10 32 22 40 213 -53 175 13 14 177 43 52 173 50 3 179 19 48 178 10 50 19 0 0 10 33 41 40 216 -55 176 52 53 179 32 55 175 25 22 -178 43 48 -179 55 45 18 0 0 10 35 5 39 218 -57 178 40 43 -178 26 55 177 7 44 -176 33 36 -177 49 59 17 0 0 10 36 36 38 221 -59 -179 21 1 -176 11 48 178 58 50 -174 3 48 Latitude Latitude Latitude Latitude -177 0 0 16 38 1 10 37 11 38 222 -60 15 56 13 17 20 30 15 7 43 18 11 34 -176 0 0 16 13 2 10 37 53 38 223 -61 15 31 36 16 55 8 14 43 31 17 45 42 -175 0 0 15 49 32 10 38 34 37 224 -62 15 8 27 16 31 16 14 20 45 17 21 24 -174 0 0 15 27 31 10 39 14 37 225 -63 14 46 45 16 8 54 13 59 26 16 58 36 -173 0 0 15 6 57 10 39 53 36 226 -64 14 26 30 15 48 0 13 39 31 16 37 19 -172 0 0 14 47 49 10 40 32 35 227 -65 14 7 40 15 28 35 13 21 1 16 17 30 -171 0 0 14 30 6 10 41 9 35 228 -65 13 50 13 15 10 35 13 3 53 15 59 9 -170 0 0 14 13 48 10 41 46 34 229 -66 13 34 10 14 54 0 12 48 7 15 42 15 -169 0 0 13 58 52 10 42 22 33 230 -67 13 19 29 14 38 50 12 33 42 15 26 46 -168 0 0 13 45 18 10 42 57 33 231 -67 13 6 8 14 25 2 12 20 36 15 12 41 -167 0 0 13 33 5 10 43 31 32 232 -68 12 54 7 14 12 36 12 8 49 14 59 59 -166 0 0 13 22 12 10 44 4 31 233 -68 12 43 25 14 1 31 11 58 20 14 48 39 -165 0 0 13 12 37 10 44 36 30 233 -69 12 34 1 13 51 45 11 49 8 14 38 40 -164 0 0 13 4 20 10 45 8 30 234 -69 12 25 53 13 43 18 11 41 11 14 30 1 -163 0 0 12 57 19 10 45 38 29 235 -69 12 19 1 13 36 9 11 34 29 14 22 40 -162 0 0 12 51 34 10 46 7 28 235 -70 12 13 24 13 30 16 11 29 1 14 16 37 -161 0 0 12 47 4 10 46 36 27 236 -70 12 9 1 13 25 39 11 24 45 14 11 51 -160 0 0 12 43 48 10 47 4 26 237 -70 12 5 52 13 22 16 11 21 42 14 8 21 -159 0 0 12 41 46 10 47 30 25 237 -69 12 3 54 13 20 8 11 19 51 14 6 5 -158 0 0 12 40 55 10 47 56 24 238 -69 12 3 8 13 19 12 11 19 10 14 5 4 -157 0 0 12 41 15 10 48 20 23 238 -69 12 3 32 13 19 29 11 19 38 14 5 16 -156 0 0 12 42 46 10 48 44 23 239 -69 12 5 6 13 20 57 11 21 16 14 6 40 -155 0 0 12 45 27 10 49 7 22 239 -68 12 7 49 13 23 35 11 24 2 14 9 16 -154 0 0 12 49 17 10 49 28 21 239 -68 12 11 41 13 27 24 11 27 55 14 13 2 -153 0 0 12 54 16 10 49 49 20 240 -67 12 16 40 13 32 21 11 32 55 14 17 58 -152 0 0 13 0 22 10 50 9 19 240 -67 12 22 46 13 38 27 11 39 1 14 24 4 -151 0 0 13 7 35 10 50 27 18 241 -66 12 29 59 13 45 41 11 46 13 14 31 18 -150 0 0 13 15 54 10 50 45 17 241 -66 12 38 17 13 54 1 11 54 30 14 39 40 -149 0 0 13 25 19 10 51 2 16 241 -65 12 47 40 14 3 28 12 3 51 14 49 10 -148 0 0 13 35 49 10 51 17 15 242 -64 12 58 8 14 14 1 12 14 15 14 59 46 -147 0 0 13 47 24 10 51 32 14 242 -63 13 9 39 14 25 39 12 25 43 15 11 28 -146 0 0 14 0 3 10 51 45 13 242 -63 13 22 14 14 38 22 12 38 13 15 24 15 -145 0 0 14 13 44 10 51 58 12 243 -62 13 35 51 14 52 8 12 51 45 15 38 7 -144 0 0 14 28 29 10 52 9 11 243 -61 13 50 30 15 6 58 13 6 19 15 53 4 -143 0 0 14 44 15 10 52 20 10 243 -60 14 6 11 15 22 50 13 21 53 16 9 4 -142 0 0 15 1 4 10 52 29 9 244 -59 14 22 53 15 39 45 13 38 28 16 26 7 -141 0 0 15 18 53 10 52 38 8 244 -58 14 40 35 15 57 42 13 56 2 16 44 13 -140 0 0 15 37 43 10 52 45 7 244 -57 14 59 18 16 16 40 14 14 36 17 3 21 -139 0 0 15 57 33 10 52 51 6 244 -56 15 18 59 16 36 39 14 34 8 17 23 30 -138 0 0 16 18 23 10 52 56 5 245 -55 15 39 40 16 57 38 .. .. .. 17 44 40 -137 0 0 16 40 11 10 53 0 4 245 -54 16 1 19 17 19 36 .. .. .. 18 6 51 -136 0 0 17 2 58 10 53 4 2 245 -53 16 23 56 17 42 34 .. .. .. 18 30 2 -135 0 0 17 26 43 10 53 6 1 246 -52 16 47 30 18 6 30 .. .. .. 18 54 12 -134 0 0 17 51 26 10 53 6 0 246 -51 17 12 1 18 31 25 .. .. .. .. .. .. Uncertainty in time = +/- 17 secs [Prediction of 2008 Aug 18.0] Data for the target star ------------------------ * name: 2UCAC 22797210 * constellation : Sagittarius * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 19 17 08.7563 DE: -22 44 36.586 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .049, .049 ) * V mag [mag]: 13.0 * B mag [mag]: 0.0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (17) Thetis approx. diameter [km]: 90 approx. diameter ["]: .085 distance from Earth [AU]: 1.45800 * orbital information: orbit source: Preston date of fit: 2008 Aug 17 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 1656 number of rejected observations: 233 time covered by the observations: 1900 Oct 03 - 2008 Aug 03 1 sigma uncertainty ellipse (major, minor, PA): 0.011, 0.009, 91° remarks: * orbital elements for (17) Thetis : Mean anomaly = 36.71593593 deg Arg. of pericenter = 135.92100284 deg Long. of node = 125.59892431 deg Inclination = 5.58869792 deg Eccentricity = 0.13497436 Semimajor axis = 2.47062875 AU Perihelion dist = 2.13715722 AU Mag: H = 7.67, G = 0.15 Epoch of elements : MJD 54711.44000000 TDT (2008 Sep 02.440) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 Sep 2 17 Thetis 10h 30.8m UT 13.0 19 17 8.756-22 44 36.592UCAC 22797210 0.0 11.3 90 29.4 1.458 0.650 -5.29 149.6406 -22.741 22.20 7.69 10.5132 0.38878 0.65989 1.48704 -0.87808 0.00425 0.00059 2000 36.3504632008 9 1.00000135.921003125.598924 5.5886980.13497436 2.4706288 2.1371572 7.8 5.00.15 RATE 2.5380070 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.050 0.050 90 1.59 0.050 0 54696.5020080902_797210 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Aug 18, 06:58 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org