IOTA/IOTA-ES occultation update for (676) Melitta / TYC 6250-00522-1 event on 2012 Nov 04, 13:53 UT Visible from India Summary ------- On 2012 Nov 04 UT, the 82 km diameter asteroid (676) Melitta will occult a 9.7 mag star in the constellation Serpens for observers along a path across India. In the case of an occultation, the combined light of the asteroid and the star will drop by 5.3 mag to 15.0 mag (the magnitude of the asteroid) for at most 2.1 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: 76 * date and approx. time of event: 2012 Nov 04, 13:55 - 2012 Nov 04, 13:55 UT * geocentric midpoint of event [JD]: 2456236.07913333 * magnitude of target star: 9.7 * magnitude drop [mag]: 5.3 * estimated maximum duration [s]: 2.1 * Moon: 73 % sunlit, 164° distance * Sun: 47° distance * rough path description: India The occultation path -------------------- * approximate projected width [km]: 111 * 1 sigma uncertainty interval [path widths]: +/- 0.74 * 1 sigma uncertainty interval [seconds]: +/- 1.6 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .026 +/- .025) * 1 sigma uncertainty ellipse (major, minor, PA): ( .026", .025", 93° ) * approx speed of asteroid's shadow [km/s]: 38.6825 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 6250-00522-1 by 676 Melitta on 2012 Nov 4 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 50 0 0 24 56 7 13 55 5 38 223 0 24 26 8 25 26 21 23 42 10 26 11 33 51 0 0 24 58 44 13 55 7 37 224 -1 24 28 44 25 28 59 23 44 46 26 14 11 52 0 0 25 1 45 13 55 9 36 225 -2 24 31 44 25 32 0 23 47 45 26 17 14 53 0 0 25 5 10 13 55 11 36 225 -3 24 35 8 25 35 25 23 51 8 26 20 40 54 0 0 25 8 58 13 55 13 35 226 -4 24 38 55 25 39 14 23 54 54 26 24 30 55 0 0 25 13 9 13 55 15 34 227 -5 24 43 6 25 43 27 23 59 3 26 28 44 56 0 0 25 17 44 13 55 17 34 228 -6 24 47 40 25 48 3 24 3 36 26 33 22 57 0 0 25 22 42 13 55 19 33 229 -7 24 52 37 25 53 2 24 8 31 26 38 23 58 0 0 25 28 4 13 55 21 32 229 -7 24 57 58 25 58 25 24 13 50 26 43 47 59 0 0 25 33 48 13 55 23 31 230 -8 25 3 41 26 4 10 24 19 31 26 49 35 60 0 0 25 39 56 13 55 25 31 231 -9 25 9 47 26 10 19 24 25 36 26 55 45 61 0 0 25 46 26 13 55 27 30 232 -10 25 16 16 26 16 51 24 32 2 27 2 19 62 0 0 25 53 19 13 55 29 29 232 -11 25 23 7 26 23 45 24 38 52 27 9 16 63 0 0 26 0 34 13 55 30 28 233 -12 25 30 21 26 31 2 24 46 3 27 16 35 64 0 0 26 8 12 13 55 32 27 234 -13 25 37 57 26 38 42 24 53 37 27 24 17 65 0 0 26 16 12 13 55 33 27 234 -14 25 45 55 26 46 43 25 1 33 27 32 22 66 0 0 26 24 34 13 55 35 26 235 -15 25 54 15 26 55 7 25 9 50 27 40 48 67 0 0 26 33 18 13 55 37 25 236 -16 26 2 57 27 3 53 25 18 30 27 49 37 68 0 0 26 42 23 13 55 38 24 236 -17 26 12 1 27 13 0 25 27 30 27 58 47 69 0 0 26 51 50 13 55 39 23 237 -17 26 21 26 27 22 29 25 36 52 28 8 19 70 0 0 27 1 38 13 55 41 22 237 -18 26 31 11 27 32 19 25 46 35 28 18 13 71 0 0 27 11 47 13 55 42 22 238 -19 26 41 18 27 42 30 25 56 39 28 28 27 72 0 0 27 22 16 13 55 43 21 239 -20 26 51 46 27 53 2 26 7 3 28 39 2 73 0 0 27 33 7 13 55 45 20 239 -21 27 2 34 28 3 55 26 17 48 28 49 59 74 0 0 27 44 17 13 55 46 19 240 -22 27 13 42 28 15 7 26 28 53 29 1 15 75 0 0 27 55 48 13 55 47 18 240 -23 27 25 10 28 26 40 26 40 18 29 12 52 76 0 0 28 7 38 13 55 48 17 241 -24 27 36 58 28 38 33 26 52 2 29 24 48 77 0 0 28 19 48 13 55 49 16 241 -25 27 49 5 28 50 45 27 4 6 29 37 4 78 0 0 28 32 16 13 55 50 16 242 -26 28 1 32 29 3 17 27 16 29 29 49 40 79 0 0 28 45 4 13 55 51 15 243 -26 28 14 17 29 16 7 27 29 10 30 2 34 80 0 0 28 58 11 13 55 52 14 243 -27 28 27 21 29 29 16 27 42 10 30 15 47 81 0 0 29 11 35 13 55 53 13 244 -28 28 40 42 29 42 43 27 55 28 30 29 18 82 0 0 29 25 18 13 55 53 12 244 -29 28 54 22 29 56 29 28 9 4 30 43 8 83 0 0 29 39 18 13 55 54 11 245 -30 29 8 20 30 10 31 28 22 58 30 57 15 84 0 0 29 53 35 13 55 55 10 245 -31 29 22 34 30 24 52 28 37 8 31 11 39 85 0 0 30 8 9 13 55 55 9 246 -32 29 37 6 30 39 29 28 51 36 31 26 21 86 0 0 30 23 0 13 55 56 8 246 -33 29 51 54 30 54 22 29 6 20 31 41 19 87 0 0 30 38 7 13 55 56 8 247 -34 30 6 58 31 9 32 29 21 20 31 56 33 88 0 0 30 53 30 13 55 57 7 247 -34 30 22 18 31 24 58 29 36 36 32 12 3 89 0 0 31 9 8 13 55 57 6 248 -35 30 37 53 31 40 39 29 52 7 32 27 49 90 0 0 31 25 1 13 55 58 5 248 -36 30 53 43 31 56 35 30 7 53 32 43 49 91 0 0 31 41 9 13 55 58 4 249 -37 31 9 48 32 12 46 .. .. .. 33 0 5 92 0 0 31 57 31 13 55 58 3 249 -38 31 26 7 32 29 10 .. .. .. 33 16 34 93 0 0 32 14 6 13 55 58 2 250 -39 31 42 40 32 45 49 .. .. .. 33 33 17 94 0 0 32 30 55 13 55 58 1 250 -39 31 59 26 33 2 41 .. .. .. 33 50 14 95 0 0 32 47 57 13 55 58 0 251 -40 32 16 25 33 19 46 .. .. .. 34 7 23 Uncertainty in time = +/- 2 secs Prediction of 2012 Oct 26.0 Data for the target star ------------------------ * name: TYC 6250-00522-1 * constellation : Serpens * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 17 55 49.2257 DE: -15 41 47.787 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .022, .024 ) * V mag [mag]: 9.7 * B mag [mag]: 10.0 * Diameter [mas]: 0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (676) Melitta approx. diameter [km]: 82 approx. diameter ["]: .034 distance from Earth [AU]: 3.36400 * orbital information: orbit source: Preston date of fit: 2012 Sep 08 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 1217 number of rejected observations: 68 time covered by the observations: 1909 Jan 17 - 2012 Jul 19 1 sigma uncertainty ellipse (major, minor, PA): 0.014, 0.008, 99° remarks: * orbital elements for (676) Melitta : Mean anomaly = 321.08747433 deg Arg. of pericenter = 182.12497332 deg Long. of node = 150.38610154 deg Inclination = 12.86255604 deg Eccentricity = 0.12457694 Semimajor axis = 3.06106276 AU Perihelion dist = 2.67972494 AU Mag: H = 9.36, G = 0.15 Epoch of elements : MJD 56235.57900000 TDT (2012 Nov 04.579) ------ occelmnt file for Occult BEGIN ----------------------------------- 2012 Nov 4 676 Melitta 13h 53.9m UT 9.7 17 55 49.226-15 41 47.79TYC 6250-00522-1 10.0 15.0 82 2.1 3.364 3.913 -8.02 16.2540 -15.694 -32.59 -15.61 13.8992 0.09812 0.66512 21.61640 -3.07135 0.00426 0.00051 2000 320.06075420121030.00000182.124973150.386102 12.8625560.12457694 3.0610628 2.6797249 9.3 5.00.15 RATE 1.8403300 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.026 0.025 93 1.74 0.025 0 0-3 3 056226.0020121104_0522-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2012 Sep 07, 23:41 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org