IOTA/IOTA-ES occultation update for (283) Emma / TYC 6860-00167-1 event on 2008 Oct 14, 14:54 UT Visible from S India Summary ------- On 2008 Oct 14 UT, the 148 km diameter asteroid (283) Emma will occult a 11.3 mag star in the constellation Sagittarius for observers along a path across S India. In the case of an occultation, the combined light of the asteroid and the star will drop by 2.9 mag to 14.1 mag (the magnitude of the asteroid) for at most 6.9 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: 84 * date and approx. time of event: 2008 Oct 14, 14:55 - 2008 Oct 14, 14:59 UT * magnitude of target star: 11.3 * magnitude drop [mag]: 2.9 * estimated maximum duration [s]: 6.9 * Moon: 100 % sunlit, 96° distance * Sun: 82° distance * rough path description: S India The occultation path -------------------- * approximate projected width [km]: 152 * 1 sigma uncertainty interval [path widths]: +/- 0.61 * 1 sigma uncertainty interval [seconds]: +/- 3.0 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .035 +/- .047) * 1 sigma uncertainty ellipse (major, minor, PA): ( .047", .035", 359° ) * approx speed of asteroid's shadow [km/s]: 21.4656 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 6860-00167-1 by 283 Emma on 2008 Oct 14 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 ' " Latitude Latitude Latitude Latitude 44 0 0 - 6 58 17 14 55 4 73 201 0 - 7 41 11 - 6 15 14 - 8 33 22 - 5 22 31 45 0 0 - 6 40 53 14 55 10 72 204 -1 - 7 23 53 - 5 57 45 - 8 16 10 - 5 4 56 46 0 0 - 6 23 3 14 55 15 72 206 -2 - 7 6 8 - 5 39 50 - 7 58 30 - 4 46 54 47 0 0 - 6 4 46 14 55 20 71 208 -3 - 6 47 56 - 5 21 28 - 7 40 25 - 4 28 26 48 0 0 - 5 46 2 14 55 26 70 210 -4 - 6 29 18 - 5 2 39 - 7 21 53 - 4 9 31 49 0 0 - 5 26 53 14 55 31 69 212 -6 - 6 10 13 - 4 43 24 - 7 2 55 - 3 50 9 50 0 0 - 5 7 18 14 55 36 69 214 -7 - 5 50 43 - 4 23 43 - 6 43 31 - 3 30 22 51 0 0 - 4 47 16 14 55 42 68 215 -8 - 5 30 47 - 4 3 37 - 6 23 42 - 3 10 9 52 0 0 - 4 26 50 14 55 47 67 217 -9 - 5 10 26 - 3 43 5 - 6 3 27 - 2 49 31 53 0 0 - 4 5 59 14 55 52 66 218 -10 - 4 49 40 - 3 22 9 - 5 42 48 - 2 28 27 54 0 0 - 3 44 43 14 55 58 65 219 -11 - 4 28 30 - 3 0 47 - 5 21 44 - 2 6 59 55 0 0 - 3 23 2 14 56 3 64 220 -12 - 4 6 55 - 2 39 1 - 5 0 15 - 1 45 6 56 0 0 - 3 0 58 14 56 8 63 221 -13 - 3 44 56 - 2 16 51 - 4 38 23 - 1 22 50 57 0 0 - 2 38 30 14 56 13 62 222 -14 - 3 22 33 - 1 54 18 - 4 16 7 - 1 0 10 58 0 0 - 2 15 39 14 56 18 61 223 -15 - 2 59 47 - 1 31 21 - 3 53 27 - 0 37 7 59 0 0 - 1 52 25 14 56 23 60 224 -16 - 2 36 39 - 1 8 2 - 3 30 25 - 0 13 41 60 0 0 - 1 28 49 14 56 28 59 225 -17 - 2 13 8 - 0 44 20 - 3 7 1 0 10 8 61 0 0 - 1 4 50 14 56 33 58 225 -18 - 1 49 15 - 0 20 17 - 2 43 14 0 34 18 62 0 0 - 0 40 31 14 56 38 57 226 -19 - 1 25 1 0 4 8 - 2 19 6 0 58 49 63 0 0 - 0 15 51 14 56 43 56 227 -20 - 1 0 26 0 28 53 - 1 54 38 1 23 41 64 0 0 0 9 10 14 56 48 55 227 -22 - 0 35 30 0 53 59 - 1 29 48 1 48 53 65 0 0 0 34 30 14 56 53 54 228 -23 - 0 10 15 1 19 25 - 1 4 39 2 14 25 66 0 0 1 0 10 14 56 58 53 228 -24 0 15 20 1 45 10 - 0 39 10 2 40 16 67 0 0 1 26 9 14 57 2 52 229 -25 0 41 13 2 11 13 - 0 13 23 3 6 25 68 0 0 1 52 25 14 57 7 51 229 -26 1 7 25 2 37 34 0 12 43 3 32 53 69 0 0 2 18 59 14 57 12 50 230 -27 1 33 54 3 4 13 0 39 6 3 59 37 70 0 0 2 45 49 14 57 16 49 230 -28 2 0 40 3 31 8 1 5 47 4 26 38 71 0 0 3 12 56 14 57 20 48 230 -29 2 27 42 3 58 19 1 32 43 4 53 55 72 0 0 3 40 18 14 57 25 47 231 -30 2 55 0 4 25 46 1 59 56 5 21 27 73 0 0 4 7 55 14 57 29 46 231 -31 3 22 33 4 53 27 2 27 23 5 49 13 74 0 0 4 35 46 14 57 33 45 232 -32 3 50 19 5 21 22 2 55 5 6 17 13 75 0 0 5 3 50 14 57 37 43 232 -33 4 18 20 5 49 30 3 23 1 6 45 26 76 0 0 5 32 7 14 57 41 42 232 -34 4 46 32 6 17 50 3 51 9 7 13 51 77 0 0 6 0 35 14 57 45 41 232 -35 5 14 57 6 46 22 4 19 29 7 42 28 78 0 0 6 29 14 14 57 49 40 233 -36 5 43 33 7 15 5 4 48 1 8 11 15 79 0 0 6 58 4 14 57 53 39 233 -37 6 12 19 7 43 58 5 16 43 8 40 12 80 0 0 7 27 3 14 57 57 38 233 -39 6 41 15 8 13 0 5 45 35 9 9 18 81 0 0 7 56 11 14 58 1 37 234 -40 7 10 20 8 42 11 6 14 36 9 38 32 82 0 0 8 25 26 14 58 4 36 234 -41 7 39 33 9 11 29 6 43 46 10 7 54 83 0 0 8 54 48 14 58 7 35 234 -42 8 8 52 9 40 54 7 13 2 10 37 22 84 0 0 9 24 17 14 58 11 34 235 -43 8 38 18 10 10 25 7 42 25 11 6 56 85 0 0 9 53 50 14 58 14 33 235 -44 9 7 50 10 40 1 8 11 54 11 36 34 86 0 0 10 23 28 14 58 17 31 235 -45 9 37 26 11 9 40 8 41 28 12 6 17 87 0 0 10 53 10 14 58 20 30 235 -46 10 7 6 11 39 24 9 11 6 12 36 2 88 0 0 11 22 54 14 58 23 29 236 -47 10 36 48 12 9 10 9 40 46 13 5 50 89 0 0 11 52 40 14 58 26 28 236 -48 11 6 33 12 38 57 10 10 30 13 35 39 90 0 0 12 22 27 14 58 29 27 236 -49 11 36 19 13 8 45 10 40 14 14 5 29 91 0 0 12 52 14 14 58 31 26 237 -50 12 6 5 13 38 33 11 9 59 14 35 18 92 0 0 13 22 1 14 58 34 25 237 -51 12 35 51 14 8 21 11 39 44 15 5 6 93 0 0 13 51 46 14 58 36 24 237 -52 13 5 36 14 38 6 12 9 28 15 34 52 94 0 0 14 21 28 14 58 39 23 237 -52 13 35 18 15 7 49 12 39 10 16 4 35 95 0 0 14 51 8 14 58 41 22 238 -53 14 4 57 15 37 28 13 8 50 16 34 14 96 0 0 15 20 43 14 58 43 21 238 -54 14 34 33 16 7 3 13 38 25 17 3 49 97 0 0 15 50 13 14 58 45 19 238 -55 15 4 3 16 36 33 14 7 57 17 33 18 98 0 0 16 19 38 14 58 47 18 239 -56 15 33 29 17 5 57 14 37 23 18 2 41 99 0 0 16 48 56 14 58 48 17 239 -57 16 2 48 17 35 14 15 6 43 18 31 58 100 0 0 17 18 7 14 58 50 16 239 -58 16 32 0 18 4 24 15 35 56 19 1 6 101 0 0 17 47 10 14 58 52 15 240 -59 17 1 4 18 33 26 16 5 2 19 30 6 102 0 0 18 16 4 14 58 53 14 240 -59 17 30 0 19 2 18 16 33 59 19 58 57 103 0 0 18 44 49 14 58 54 13 240 -60 17 58 46 19 31 1 17 2 48 20 27 38 104 0 0 19 13 24 14 58 56 12 241 -61 18 27 23 19 59 34 17 31 27 20 56 8 105 0 0 19 41 47 14 58 57 11 241 -62 18 55 48 20 27 56 17 59 55 21 24 27 106 0 0 20 9 59 14 58 58 10 241 -63 19 24 3 20 56 5 18 28 12 21 52 34 107 0 0 20 37 59 14 58 59 9 242 -63 19 52 5 21 24 3 18 56 17 22 20 28 108 0 0 21 5 46 14 58 59 8 242 -64 20 19 55 21 51 47 19 24 10 22 48 9 109 0 0 21 33 20 14 59 0 7 242 -64 20 47 31 22 19 18 19 51 50 23 15 36 110 0 0 22 0 39 14 59 1 6 243 -65 21 14 54 22 46 34 20 19 16 23 42 49 111 0 0 22 27 44 14 59 1 5 243 -66 21 42 2 23 13 36 20 46 28 24 9 46 112 0 0 22 54 33 14 59 2 4 244 -66 22 8 54 23 40 22 21 13 25 24 36 28 113 0 0 23 21 7 14 59 2 3 244 -67 22 35 32 24 6 52 21 40 6 25 2 54 114 0 0 23 47 25 14 59 2 2 244 -67 23 1 53 24 33 6 22 6 32 25 29 4 115 0 0 24 13 25 14 59 2 1 245 -68 23 27 57 24 59 3 22 32 41 .. .. .. Uncertainty in time = +/- 4 secs [Prediction of 2008 Oct 1.0] Data for the target star ------------------------ * name: TYC 6860-00167-1 * constellation : Sagittarius * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 18 58 22.5374 DE: -22 43 48.459 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .032, .046 ) * V mag [mag]: 11.3 * B mag [mag]: 12.7 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (283) Emma approx. diameter [km]: 148 approx. diameter ["]: .076 distance from Earth [AU]: 2.68500 * orbital information: orbit source: Preston date of fit: 2008 Sep 30 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 842 number of rejected observations: 102 time covered by the observations: 1913 Sep 25 - 2008 Sep 20 1 sigma uncertainty ellipse (major, minor, PA): 0.014, 0.010, 74° remarks: * orbital elements for (283) Emma : Mean anomaly = 319.87023886 deg Arg. of pericenter = 53.24313069 deg Long. of node = 304.41926084 deg Inclination = 7.99765826 deg Eccentricity = 0.15084917 Semimajor axis = 3.04771217 AU Perihelion dist = 2.58796732 AU Mag: H = 8.47, G = 0.15 Epoch of elements : MJD 54753.62100000 TDT (2008 Oct 14.621) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 Oct 14 283 Emma 14h 54.2m UT 11.3 18 58 22.537-22 43 48.46TYC 6860-00167-1 12.7 14.1 148 6.9 2.685 2.798 8.74 37.5116 -22.732 -47.08 -8.43 14.9038 -0.05285 0.23208 11.81801 2.66972 0.00564 0.00057 2000 319.19947220081011.00000 53.243131304.419261 7.9976580.15084917 3.0477122 2.5879673 8.7 5.00.15 RATE 1.8524360 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.047 0.035 359 1.61 0.046 1 12 510 54740.5020081014_0167-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Oct 01, 04:54 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org