IOTA/IOTA-ES occultation update for (770) Bali / TYC 6815-00883-1 event on 2008 May 11, 22:41 UT Visible from SW Asia, Arabia, Africa Summary ------- On 2008 May 11 UT, the 16 km diameter asteroid (770) Bali will occult a 10.4 mag star in the constellation Ophiuchus for observers along a path across SW Asia, Arabia, Africa. In the case of an occultation, the combined light of the asteroid and the star will drop by 4.2 mag to 14.6 mag (the magnitude of the asteroid) for at most 1.7 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: 17 * date and approx. time of event: 2008 May 11, 22:33 - 2008 May 11, 22:47 UT * magnitude of target star: 10.4 * magnitude drop [mag]: 4.2 * estimated maximum duration [s]: 1.7 * Moon: 47 % sunlit, 119° distance * Sun: 154° distance * rough path description: SW Asia, Arabia, Africa The occultation path -------------------- * approximate projected width [km]: 24 * 1 sigma uncertainty interval [path widths]: +/- 4.02 * 1 sigma uncertainty interval [seconds]: +/- 5.1 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .047 +/- .056) * 1 sigma uncertainty ellipse (major, minor, PA): ( .056", .047", 1° ) * approx speed of asteroid's shadow [km/s]: 9.6286 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 6815-00883-1 by 770 Bali on 2008 May 11 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 92 50 29 39 0 0 22 33 53 13 221 -2 92 34 43 93 6 11 90 26 9 95 10 46 90 51 19 38 0 0 22 34 0 15 220 -4 90 35 22 91 7 12 88 25 9 93 13 3 88 49 17 37 0 0 22 34 9 16 219 -5 88 33 6 89 5 23 86 20 48 91 12 52 Latitude Latitude Latitude Latitude 87 0 0 36 7 37 22 34 18 18 217 -7 36 15 23 35 59 52 37 18 44 34 58 26 86 0 0 35 39 25 22 34 23 19 217 -8 35 47 9 35 31 43 36 50 8 34 30 36 85 0 0 35 11 38 22 34 28 20 216 -9 35 19 19 35 3 59 36 21 58 34 3 11 84 0 0 34 44 17 22 34 34 21 215 -10 34 51 56 34 36 40 35 54 14 33 36 11 83 0 0 34 17 22 22 34 40 21 215 -11 34 24 59 34 9 48 35 26 57 33 9 37 82 0 0 33 50 55 22 34 46 22 214 -12 33 58 29 33 43 22 35 0 6 32 43 30 81 0 0 33 24 55 22 34 52 23 213 -13 33 32 26 33 17 24 34 33 44 32 17 50 80 0 0 32 59 22 22 34 58 24 212 -14 33 6 52 32 51 55 34 7 51 31 52 38 79 0 0 32 34 19 22 35 5 25 212 -14 32 41 46 32 26 53 33 42 26 31 27 54 78 0 0 32 9 45 22 35 12 25 211 -15 32 17 9 32 2 21 33 17 31 31 3 39 77 0 0 31 45 40 22 35 19 26 210 -16 31 53 2 31 38 18 32 53 6 30 39 53 76 0 0 31 22 5 22 35 26 27 209 -17 31 29 25 31 14 46 32 29 11 30 16 37 75 0 0 30 59 0 22 35 33 28 209 -18 31 6 19 30 51 43 32 5 47 29 53 50 74 0 0 30 36 27 22 35 41 28 208 -19 30 43 43 30 29 12 31 42 54 29 31 34 73 0 0 30 14 24 22 35 49 29 207 -20 30 21 38 30 7 11 31 20 33 29 9 49 72 0 0 29 52 53 22 35 56 30 206 -21 30 0 5 29 45 42 30 58 44 28 48 34 71 0 0 29 31 53 22 36 4 30 205 -22 29 39 4 29 24 44 30 37 27 28 27 51 70 0 0 29 11 26 22 36 13 31 205 -23 29 18 35 29 4 19 30 16 42 28 7 40 69 0 0 28 51 31 22 36 21 32 204 -23 28 58 38 28 44 25 29 56 31 27 48 0 68 0 0 28 32 9 22 36 29 32 203 -24 28 39 14 28 25 4 29 36 52 27 28 53 67 0 0 28 13 19 22 36 38 33 202 -25 28 20 22 28 6 16 29 17 47 27 10 18 66 0 0 27 55 2 22 36 47 34 201 -26 28 2 4 27 48 1 28 59 15 26 52 15 65 0 0 27 37 19 22 36 56 34 200 -27 27 44 19 27 30 20 28 41 17 26 34 46 64 0 0 27 20 9 22 37 4 35 199 -28 27 27 8 27 13 11 28 23 53 26 17 49 63 0 0 27 3 32 22 37 14 35 198 -28 27 10 30 26 56 36 28 7 3 26 1 25 62 0 0 26 47 30 22 37 23 36 197 -29 26 54 26 26 40 35 27 50 47 25 45 35 61 0 0 26 32 1 22 37 32 36 196 -30 26 38 56 26 25 8 27 35 5 25 30 18 60 0 0 26 17 6 22 37 41 37 195 -31 26 24 0 26 10 14 27 19 58 25 15 35 59 0 0 26 2 46 22 37 51 37 194 -32 26 9 38 25 55 55 27 5 26 25 1 25 58 0 0 25 49 0 22 38 0 38 193 -32 25 55 50 25 42 10 26 51 29 24 47 50 57 0 0 25 35 48 22 38 10 38 192 -33 25 42 37 25 28 59 26 38 6 24 34 48 56 0 0 25 23 10 22 38 20 38 191 -34 25 29 59 25 16 23 26 25 19 24 22 20 55 0 0 25 11 8 22 38 29 39 190 -35 25 17 55 25 4 21 26 13 6 24 10 27 54 0 0 24 59 40 22 38 39 39 189 -35 25 6 26 24 52 54 26 1 29 23 59 7 53 0 0 24 48 46 22 38 49 39 188 -36 24 55 32 24 42 2 25 50 27 23 48 22 52 0 0 24 38 28 22 38 59 40 187 -37 24 45 12 24 31 44 25 40 0 23 38 11 51 0 0 24 28 44 22 39 9 40 186 -37 24 35 28 24 22 1 25 30 9 23 28 35 50 0 0 24 19 36 22 39 19 40 185 -38 24 26 19 24 12 54 25 20 53 23 19 33 49 0 0 24 11 2 22 39 29 40 184 -39 24 17 44 24 4 21 25 12 12 23 11 6 48 0 0 24 3 3 22 39 39 41 183 -39 24 9 45 23 56 23 25 4 7 23 3 13 47 0 0 23 55 40 22 39 50 41 181 -40 24 2 21 23 49 0 24 56 38 22 55 55 46 0 0 23 48 52 22 40 0 41 180 -41 23 55 32 23 42 12 24 49 44 22 49 12 45 0 0 23 42 38 22 40 10 41 179 -41 23 49 18 23 36 0 24 43 26 22 43 4 44 0 0 23 37 1 22 40 20 41 178 -42 23 43 40 23 30 22 24 37 44 22 37 30 43 0 0 23 31 58 22 40 30 41 177 -42 23 38 37 23 25 20 24 32 38 22 32 31 42 0 0 23 27 31 22 40 40 41 176 -43 23 34 9 23 20 53 24 28 7 22 28 7 41 0 0 23 23 39 22 40 51 41 174 -43 23 30 17 23 17 1 24 24 12 22 24 18 40 0 0 23 20 22 22 41 1 41 173 -44 23 27 0 23 13 45 24 20 53 22 21 3 39 0 0 23 17 41 22 41 11 41 172 -44 23 24 19 23 11 4 24 18 10 22 18 24 38 0 0 23 15 35 22 41 21 41 171 -45 23 22 13 23 8 58 24 16 2 22 16 20 37 0 0 23 14 5 22 41 31 41 170 -45 23 20 42 23 7 28 24 14 31 22 14 50 36 0 0 23 13 10 22 41 41 41 169 -45 23 19 47 23 6 33 24 13 36 22 13 56 35 0 0 23 12 50 22 41 51 40 168 -46 23 19 28 23 6 14 24 13 16 22 13 36 34 0 0 23 13 7 22 42 1 40 167 -46 23 19 44 23 6 30 24 13 33 22 13 52 33 0 0 23 13 58 22 42 11 40 166 -46 23 20 36 23 7 21 24 14 25 22 14 43 32 0 0 23 15 25 22 42 21 40 164 -47 23 22 3 23 8 48 24 15 54 22 16 9 31 0 0 23 17 28 22 42 31 39 163 -47 23 24 6 23 10 51 24 17 58 22 18 10 30 0 0 23 20 6 22 42 41 39 162 -47 23 26 44 23 13 29 24 20 39 22 20 46 29 0 0 23 23 20 22 42 51 39 161 -47 23 29 58 23 16 42 24 23 55 22 23 57 28 0 0 23 27 9 22 43 1 38 160 -47 23 33 48 23 20 31 24 27 48 22 27 43 27 0 0 23 31 34 22 43 10 38 159 -48 23 38 13 23 24 56 24 32 17 22 32 4 26 0 0 23 36 35 22 43 20 38 158 -48 23 43 14 23 29 56 24 37 22 22 37 1 25 0 0 23 42 11 22 43 29 37 157 -48 23 48 51 23 35 31 24 43 3 22 42 32 24 0 0 23 48 22 22 43 39 37 156 -48 23 55 3 23 41 43 24 49 20 22 48 39 23 0 0 23 55 10 22 43 48 36 155 -48 24 1 51 23 48 29 24 56 13 22 55 21 22 0 0 24 2 33 22 43 57 36 154 -48 24 9 15 23 55 51 25 3 42 23 2 38 21 0 0 24 10 31 22 44 6 35 153 -48 24 17 14 24 3 49 25 11 47 23 10 30 20 0 0 24 19 5 22 44 15 35 153 -48 24 25 48 24 12 22 25 20 28 23 18 57 19 0 0 24 28 14 22 44 24 34 152 -47 24 34 59 24 21 31 25 29 45 23 27 59 18 0 0 24 37 59 22 44 33 34 151 -47 24 44 44 24 31 15 25 39 38 23 37 36 17 0 0 24 48 19 22 44 42 33 150 -47 24 55 6 24 41 34 25 50 7 23 47 48 16 0 0 24 59 15 22 44 50 33 149 -47 25 6 3 24 52 29 26 1 12 23 58 35 15 0 0 25 10 46 22 44 59 32 148 -47 25 17 35 25 3 59 26 12 53 24 9 57 14 0 0 25 22 53 22 45 7 31 148 -46 25 29 42 25 16 5 26 25 10 24 21 54 13 0 0 25 35 35 22 45 15 31 147 -46 25 42 25 25 28 45 26 38 3 24 34 26 12 0 0 25 48 52 22 45 23 30 146 -46 25 55 44 25 42 1 26 51 31 24 47 32 11 0 0 26 2 44 22 45 31 29 145 -45 26 9 37 25 55 52 27 5 35 25 1 14 10 0 0 26 17 11 22 45 38 29 144 -45 26 24 6 26 10 18 27 20 15 25 15 29 9 0 0 26 32 14 22 45 46 28 144 -45 26 39 9 26 25 19 27 35 30 25 30 20 8 0 0 26 47 51 22 45 53 27 143 -44 26 54 48 26 40 54 27 51 20 25 45 44 7 0 0 27 4 2 22 46 1 26 142 -44 27 11 1 26 57 5 28 7 46 26 1 43 6 0 0 27 20 49 22 46 8 26 142 -43 27 27 49 27 13 50 28 24 46 26 18 16 5 0 0 27 38 10 22 46 14 25 141 -43 27 45 12 27 31 9 28 42 22 26 35 23 4 0 0 27 56 5 22 46 21 24 140 -42 28 3 9 27 49 3 29 0 33 26 53 4 3 0 0 28 14 35 22 46 27 23 140 -42 28 21 40 28 7 30 29 19 18 27 11 19 2 0 0 28 33 38 22 46 34 23 139 -41 28 40 45 28 26 32 29 38 38 27 30 7 1 0 0 28 53 15 22 46 40 22 138 -40 29 0 24 28 46 7 29 58 32 27 49 28 0 0 0 29 13 26 22 46 46 21 138 -40 29 20 36 29 6 16 30 19 0 28 9 23 - 1 0 0 29 34 10 22 46 51 20 137 -39 29 41 22 29 26 58 30 40 2 28 29 50 - 2 0 0 29 55 27 22 46 57 19 136 -39 30 2 41 29 48 13 31 1 37 28 50 50 - 3 0 0 30 17 16 22 47 2 18 136 -38 30 24 33 30 10 1 31 23 45 29 12 23 - 4 0 0 30 39 39 22 47 7 18 135 -37 30 46 57 30 32 21 31 46 27 29 34 27 - 5 0 0 31 2 33 22 47 12 17 135 -36 31 9 54 30 55 14 32 9 41 29 57 3 - 6 0 0 31 25 59 22 47 16 16 134 -36 31 33 22 31 18 37 32 33 27 30 20 10 - 7 0 0 31 49 56 22 47 21 15 133 -35 31 57 21 31 42 33 32 57 45 30 43 48 - 8 0 0 32 14 25 22 47 25 14 133 -34 32 21 52 32 6 59 33 22 35 31 7 57 - 9 0 0 32 39 24 22 47 29 13 132 -33 32 46 53 32 31 55 33 47 55 31 32 36 - 10 0 0 33 4 52 22 47 32 12 132 -33 33 12 24 32 57 22 34 13 46 31 57 44 - 11 0 0 33 30 51 22 47 35 11 131 -32 33 38 25 33 23 18 34 40 6 32 23 22 - 12 0 0 33 57 18 22 47 39 10 131 -31 34 4 55 33 49 43 35 6 56 32 49 28 - 13 0 0 34 24 14 22 47 41 10 130 -30 34 31 53 34 16 36 35 34 15 33 16 3 - 14 0 0 34 51 37 22 47 44 9 129 -29 34 59 19 34 43 57 36 2 2 33 43 5 - 15 0 0 35 19 28 22 47 46 8 129 -29 35 27 12 35 11 45 36 30 17 34 10 33 - 16 0 0 35 47 45 22 47 48 7 128 -28 35 55 32 35 40 0 36 58 58 34 38 28 - 17 0 0 36 16 28 22 47 50 6 128 -27 36 24 17 36 8 40 37 28 5 35 6 49 - 18 0 0 36 45 36 22 47 52 5 127 -26 36 53 28 36 37 45 37 57 38 .. .. .. - 19 0 0 37 15 8 22 47 53 4 126 -25 37 23 2 37 7 15 38 27 34 .. .. .. - 20 0 0 37 45 3 22 47 54 3 126 -24 37 53 0 37 37 7 38 57 55 .. .. .. - 21 0 0 38 15 21 22 47 55 2 125 -23 38 23 21 38 7 22 39 28 38 .. .. .. - 22 0 0 38 46 0 22 47 55 1 125 -22 38 54 3 38 37 59 39 59 42 .. .. .. - 23 0 0 39 17 0 22 47 55 0 124 -22 39 25 5 39 8 56 .. .. .. .. .. .. Uncertainty in time = +/- 7 secs [Prediction of 2008 May 8.0] Data for the target star ------------------------ * name: TYC 6815-00883-1 * constellation : Ophiuchus * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 17 03 00.2148 DE: -25 28 45.968 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .039, .053 ) * V mag [mag]: 10.4 * B mag [mag]: 11.5 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (770) Bali approx. diameter [km]: 16 approx. diameter ["]: .014 distance from Earth [AU]: 1.60800 * orbital information: orbit source: Preston date of fit: 2008 May 07 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 791 number of rejected observations: 87 time covered by the observations: 1903 Oct 20 - 2008 Apr 30 1 sigma uncertainty ellipse (major, minor, PA): 0.025, 0.019, 99° remarks: * orbital elements for (770) Bali : Mean anomaly = 186.47879704 deg Arg. of pericenter = 17.70288018 deg Long. of node = 44.80446530 deg Inclination = 4.38818792 deg Eccentricity = 0.15102869 Semimajor axis = 2.22113581 AU Perihelion dist = 1.88568058 AU Mag: H = 10.90, G = 0.15 Epoch of elements : MJD 54597.94500000 TDT (2008 May 11.945) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 May 11 770 Bali 22h 40.7m UT 10.4 17 3 0.215-25 28 45.97TYC 6815-00883-1 11.5 14.6 16 1.7 1.608 -2.190 -2.33 45.4980 -25.478 -161.08 18.16 22.6780 -0.05881 0.75131 -5.41781 -0.42737 -0.00233 0.00046 2000 184.1132302008 5 4.00000 17.702880 44.804465 4.3881880.15102869 2.2211358 1.885680610.9 5.00.15 RATE 2.9774290 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.056 0.047 1 5.02 0.055 0 54594.5020080511_0883-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 May 08, 03:03 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org