IOTA/IOTA-ES occultation update for (198) Ampella / 2UCAC 39610922 event on 2008 Jan 02, 18:21 UT Visible from Russia, China Summary ------- On 2008 Jan 02 UT, the 57 km diameter asteroid (198) Ampella will occult a 12.1 mag star in the constellation Aries for observers along a path across Russia, China. In the case of an occultation, the combined light of the asteroid and the star will drop by 0.6 mag to 11.8 mag (the magnitude of the asteroid) for at most 12.0 seconds. This update is based on UNSO/Flagstaff astrometry for the asteroid kindly provided by Alice Monet, TMO astrometry for the asteroid kindly provided by Bill Owen, historical astrometry from the MPC files (via AstDys), and the following catalogs for the star position: UCAC. The event at a glimpse ---------------------- * Rank: 91 * date and approx. time of event: 2008 Jan 02, 18:10 - 2008 Jan 02, 18:32 UT * magnitude of target star: 12.1 * magnitude drop [mag]: 0.6 * estimated maximum duration [s]: 12.0 * Moon: 27 % sunlit, 168° distance * Sun: 129° distance * rough path description: Russia, China The occultation path -------------------- * approximate projected width [km]: 113 * 1 sigma uncertainty interval [path widths]: +/- 0.51 * 1 sigma uncertainty interval [seconds]: +/- 5.8 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .028 +/- .027) * 1 sigma uncertainty ellipse (major, minor, PA): ( .028", .027", 86° ) * approx speed of asteroid's shadow [km/s]: 4.7685 * website for maps: http://lunar-occultations.com/iota/asteroids/astrndx.htm http://www.asteroidoccultation.com Path Coordinates: Occultation of 2UCAC 39610922 by 198 Ampella on 2008 Jan 02 Centre Star Star Sun Path Limit1 Path Limit2 Error Limit1 Error Limit2 E. Longitude Latitude U.T. Alt Az Alt o ' " o ' " h m s o o o o ' " o ' " o ' " o ' " o ' " o ' " o ' " o ' " Longitude Latitude Longitude Latitude Longitude Latitude Longitude Latitude ... .. .. .. .. .. .. .. .. .. .. .. ... .. .. .. .. .. ... .. .. .. .. .. ... .. .. .. .. .. 160 57 37 58 51 7 ... .. .. .. .. .. .. .. .. .. .. .. ... .. .. .. .. .. 155 45 9 60 5 34 ... .. .. .. .. .. 152 8 21 61 34 56 152 14 8 60 25 45 18 10 14 6 306 -33 156 23 10 58 39 41 149 14 58 61 34 10 ... .. .. .. .. .. 146 39 31 62 28 33 146 40 52 61 24 47 18 10 31 9 301 -35 149 21 26 60 27 10 144 19 0 62 11 48 152 43 42 59 7 29 142 6 17 62 52 39 142 10 52 61 50 41 18 10 49 11 297 -37 144 24 42 61 8 22 140 6 40 62 27 18 146 56 9 60 16 44 138 7 7 63 0 16 138 16 50 61 59 15 18 11 6 12 294 -38 140 16 1 61 25 24 136 23 48 62 29 20 142 26 8 60 45 52 134 33 27 62 56 54 134 48 47 61 56 33 18 11 23 14 291 -40 136 38 5 61 28 20 133 3 55 62 22 0 138 35 20 60 56 5 131 20 41 62 45 34 131 41 33 61 45 48 18 11 40 15 288 -41 133 23 23 61 21 42 130 3 9 62 7 45 135 11 32 60 54 30 128 25 46 62 28 12 128 51 51 61 29 0 18 11 57 16 286 -42 130 27 39 61 8 4 127 18 52 61 48 10 132 8 45 60 44 38 125 46 31 62 6 7 126 17 25 61 7 28 18 12 14 17 284 -44 127 48 6 60 49 4 124 49 6 61 24 22 129 23 25 60 28 35 123 21 10 61 40 15 123 56 25 60 42 11 18 12 31 18 282 -45 125 22 40 60 25 52 122 32 13 60 57 13 126 53 3 60 7 46 121 8 15 61 11 21 121 47 24 60 13 51 18 12 48 19 281 -46 123 9 44 59 59 17 120 26 54 60 27 18 124 35 49 59 43 9 119 6 31 60 39 58 119 49 9 59 43 3 18 13 5 20 280 -47 121 7 57 59 29 58 118 32 0 59 55 9 122 30 12 59 15 29 117 14 52 60 6 33 118 0 35 59 10 13 18 13 23 21 278 -48 119 16 11 58 58 23 116 46 29 59 21 9 120 35 0 58 45 20 115 32 21 59 31 27 116 20 47 58 35 41 18 13 40 22 277 -49 117 33 28 58 24 57 115 9 29 58 45 36 118 49 10 58 13 6 113 58 6 58 54 57 114 48 55 57 59 44 18 13 57 22 276 -50 115 58 56 57 49 58 113 40 12 58 8 47 117 11 48 57 39 10 112 31 21 58 17 17 113 24 18 57 22 37 18 14 14 23 275 -51 114 31 51 57 13 41 112 17 57 57 30 53 115 42 6 57 3 49 111 11 27 57 38 39 112 6 15 56 44 31 18 14 31 24 275 -52 113 11 32 56 36 18 111 2 6 56 52 5 114 19 23 56 27 15 109 57 46 56 59 12 110 54 12 56 5 34 18 14 48 24 274 -53 111 57 23 55 58 1 109 52 6 56 12 32 113 3 1 55 49 40 108 49 47 56 19 4 109 47 40 55 25 55 18 15 5 25 273 -53 110 48 54 55 18 57 108 47 27 55 32 21 111 52 29 55 11 14 107 47 1 55 38 22 108 46 10 54 45 41 18 15 22 25 273 -54 109 45 36 54 39 13 107 47 42 54 51 38 110 47 17 54 32 4 106 49 1 54 57 11 107 49 18 54 4 56 18 15 39 26 273 -55 108 47 3 53 58 56 106 52 28 54 10 27 109 46 58 53 52 17 105 55 25 54 15 36 106 56 42 53 23 46 18 15 56 26 272 -56 107 52 53 53 18 11 106 1 24 53 28 54 108 51 10 53 11 59 105 5 52 53 33 41 106 8 3 52 42 14 18 16 14 27 272 -57 107 2 46 52 37 1 105 14 10 52 47 1 107 59 31 52 31 13 104 20 3 52 51 28 105 23 2 52 0 24 18 16 31 27 272 -58 106 16 24 51 55 30 104 30 29 52 4 52 107 11 43 51 50 4 103 37 41 52 9 1 104 41 23 51 18 17 18 16 48 27 272 -58 105 33 29 51 13 42 103 50 5 51 22 29 106 27 28 51 8 34 102 58 31 51 26 22 104 2 53 50 35 57 18 17 5 28 272 -59 104 53 47 50 31 38 103 12 44 50 39 54 105 46 32 50 26 48 102 22 20 50 43 33 103 27 18 49 53 25 18 17 22 28 272 -60 104 17 6 49 49 20 102 38 15 49 57 9 105 8 41 49 44 46 101 48 56 50 0 35 102 54 27 49 10 43 18 17 39 28 272 -61 103 43 12 49 6 51 102 6 24 49 14 15 104 33 42 49 2 31 101 18 7 49 17 29 102 24 8 48 27 53 18 17 56 29 272 -61 103 11 55 48 24 12 101 37 3 48 31 13 104 1 24 48 20 4 100 49 43 48 34 17 101 56 13 47 44 54 18 18 13 29 272 -62 102 43 5 47 41 24 101 10 2 47 48 5 103 31 38 47 37 27 100 23 35 47 51 0 101 30 33 47 1 49 18 18 30 29 272 -63 102 16 34 46 58 27 100 45 12 47 4 51 103 4 13 46 54 41 99 59 35 47 7 38 101 7 0 46 18 37 18 18 47 29 272 -64 101 52 13 46 15 24 100 22 26 46 21 31 102 39 2 46 11 47 99 37 36 46 24 11 100 45 27 45 35 20 18 19 5 29 272 -64 101 29 55 45 32 14 100 1 37 45 38 7 102 15 57 45 28 44 99 17 31 45 40 40 100 25 47 44 51 57 18 19 22 30 273 -65 101 9 33 44 48 58 99 42 38 44 54 39 101 54 52 44 45 35 98 59 14 44 57 6 100 7 55 44 8 30 18 19 39 30 273 -66 100 51 2 44 5 36 99 25 25 44 11 6 101 35 39 44 2 19 98 42 40 44 13 28 99 51 46 43 24 57 18 19 56 30 273 -66 100 34 16 43 22 8 99 9 52 43 27 29 101 18 15 43 18 57 98 27 43 43 29 47 99 37 14 42 41 20 18 20 13 30 274 -67 100 19 10 42 38 35 98 55 54 42 43 48 101 2 34 42 35 29 98 14 19 42 46 3 99 24 16 41 57 38 18 20 30 30 274 -68 100 5 39 41 54 57 98 43 27 42 0 4 100 48 30 41 51 54 98 2 23 42 2 15 99 12 47 41 13 52 18 20 47 30 274 -68 99 53 41 41 11 13 98 32 28 41 16 14 100 36 2 41 8 13 97 51 54 41 18 24 99 2 45 40 30 0 18 21 4 30 275 -69 99 43 11 40 27 24 98 22 53 40 32 21 100 25 3 40 24 26 97 42 46 40 34 28 98 54 6 39 46 4 18 21 21 30 275 -70 99 34 7 39 43 29 98 14 39 39 48 23 100 15 33 39 40 33 97 34 58 39 50 29 98 46 47 39 2 2 18 21 39 30 275 -70 99 26 25 38 59 28 98 7 44 39 4 20 100 7 26 38 56 33 97 28 26 39 6 25 98 40 47 38 17 54 18 21 56 30 276 -71 99 20 3 38 15 20 98 2 5 38 20 12 100 0 43 38 12 26 97 23 9 38 22 17 98 36 3 37 33 40 18 22 13 30 276 -71 99 14 59 37 31 6 97 57 40 37 35 58 99 55 19 37 28 12 97 19 4 37 38 3 98 32 33 36 49 19 18 22 30 30 277 -72 99 11 11 36 46 44 97 54 27 36 51 38 99 51 13 36 43 50 97 16 9 36 53 44 98 30 15 36 4 51 18 22 47 30 277 -72 99 8 38 36 2 15 97 52 26 36 7 11 99 48 23 35 59 20 97 14 24 36 9 19 98 29 10 35 20 15 18 23 4 30 277 -73 99 7 18 35 17 38 97 51 35 35 22 37 99 46 49 35 14 40 97 13 47 35 24 46 98 29 15 34 35 31 18 23 21 29 278 -73 99 7 11 34 32 51 97 51 52 34 37 55 99 46 30 34 29 51 97 14 17 34 40 7 98 30 29 33 50 38 18 23 38 29 278 -74 99 8 15 33 47 55 97 53 17 33 53 5 99 47 24 33 44 52 97 15 54 33 55 19 98 32 54 33 5 35 18 23 55 29 279 -74 99 10 31 33 2 49 97 55 50 33 8 5 99 49 31 32 59 42 97 18 37 33 10 23 98 36 27 32 20 21 18 24 12 29 279 -75 99 13 58 32 17 31 97 59 31 32 22 55 99 52 51 32 14 20 97 22 25 32 25 16 98 41 10 31 34 56 18 24 30 28 280 -75 99 18 36 31 32 1 98 4 19 31 37 34 99 57 25 31 28 45 97 27 19 31 40 0 98 47 3 30 49 17 18 24 47 28 280 -75 99 24 26 30 46 17 98 10 16 30 52 1 100 3 13 30 42 55 97 33 19 30 54 32 98 54 6 30 3 25 18 25 4 28 281 -75 99 31 29 30 0 19 98 17 20 30 6 15 100 10 16 29 56 51 97 40 26 30 8 51 99 2 21 29 17 18 18 25 21 28 281 -75 99 39 45 29 14 5 98 25 35 29 20 14 100 18 35 29 10 30 97 48 41 29 22 57 99 11 49 28 30 55 18 25 38 27 282 -76 99 49 17 28 27 35 98 35 0 28 33 58 100 28 11 28 23 51 97 58 4 28 36 48 99 22 32 27 44 14 18 25 55 27 282 -76 100 0 6 27 40 45 98 45 38 27 47 25 100 39 8 27 36 52 98 8 37 27 50 22 99 34 32 26 57 14 18 26 12 26 283 -76 100 12 14 26 53 35 98 57 30 27 0 34 100 51 26 26 49 32 98 20 23 27 3 39 99 47 51 26 9 52 18 26 29 26 283 -75 100 25 45 26 6 3 99 10 39 26 13 22 101 5 11 26 1 49 98 33 23 26 16 37 100 2 33 25 22 7 18 26 46 26 284 -75 100 40 41 25 18 7 99 25 8 25 25 48 101 20 24 25 13 40 98 47 40 25 29 14 100 18 41 24 33 57 18 27 3 25 284 -75 100 57 8 24 29 44 99 41 0 24 37 50 101 37 11 24 25 3 99 3 18 24 41 27 100 36 20 23 45 19 18 27 21 25 285 -75 101 15 9 23 40 52 99 58 20 23 49 26 101 55 38 23 35 55 99 20 19 23 53 16 100 55 36 22 56 11 18 27 38 24 285 -74 101 34 51 22 51 27 100 17 12 23 0 32 102 15 50 22 46 12 99 38 50 23 4 36 101 16 35 22 6 28 18 27 55 23 286 -74 101 56 21 22 1 26 100 37 42 22 11 6 102 37 55 21 55 51 99 58 54 22 15 26 101 39 24 21 16 7 18 28 12 23 286 -73 102 19 47 21 10 45 100 59 58 21 21 4 103 2 3 21 4 48 100 20 39 21 25 43 102 4 12 20 25 5 18 28 29 22 286 -73 102 45 19 20 19 19 101 24 7 20 30 23 103 28 26 20 12 56 100 44 13 20 35 21 102 31 11 19 33 15 18 28 46 21 287 -72 103 13 10 19 27 3 101 50 20 19 38 57 103 57 16 19 20 10 101 9 43 19 44 18 103 0 35 18 40 31 18 29 3 21 287 -71 103 43 35 18 33 49 102 18 48 18 46 41 104 28 52 18 26 22 101 37 21 18 52 28 103 32 39 17 46 46 18 29 20 20 288 -71 104 16 53 17 39 29 102 49 47 17 53 28 105 3 35 17 31 22 102 7 20 17 59 44 104 7 46 16 51 51 18 29 37 19 288 -70 104 53 29 16 43 52 103 23 35 16 59 10 105 41 54 16 34 57 102 39 57 17 6 0 104 46 21 15 55 34 18 29 55 18 289 -69 105 33 53 15 46 45 104 0 36 16 3 37 106 24 27 15 36 52 103 15 33 16 11 7 105 29 2 14 57 38 18 30 12 17 289 -68 106 18 49 14 47 49 104 41 20 15 6 34 107 12 5 14 36 44 103 54 32 15 14 53 106 16 36 13 57 45 18 30 29 16 289 -66 107 9 16 13 46 39 105 26 27 14 7 46 108 6 2 13 34 2 104 37 31 14 17 2 107 10 13 12 55 23 18 30 46 15 290 -65 108 6 40 12 42 39 106 16 54 13 6 48 109 8 13 12 27 58 105 25 14 13 17 16 108 11 35 11 49 51 18 31 3 13 290 -64 109 13 18 11 34 51 107 14 2 12 3 6 110 21 44 11 17 15 106 18 48 12 15 7 109 23 29 10 39 58 18 31 20 12 291 -62 110 33 4 10 21 39 108 19 55 10 55 47 111 52 37 9 59 23 107 19 48 11 9 54 110 51 4 9 23 38 18 31 37 10 291 -60 112 14 6 8 59 40 109 38 5 9 43 24 113 55 42 8 28 13 108 30 49 10 0 34 112 46 0 7 55 59 18 31 54 7 291 -58 114 40 6 7 19 9 111 15 29 8 23 4 117 58 14 6 7 58 109 56 23 8 45 12 115 54 50 5 57 55 18 32 11 4 292 -54 ... .. .. .. .. .. 113 30 34 6 47 11 ... .. .. .. .. .. 111 46 25 7 19 43 Data for the target star ------------------------ * name: 2UCAC 39610922 * constellation : Aries * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 03 09 08.1971 DE: +22 05 39.338 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .021, .022 ) * V mag [mag]: 12.1 * B mag [mag]: 0.0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (198) Ampella approx. diameter [km]: 57 approx. diameter ["]: .055 distance from Earth [AU]: 1.43400 * orbital information: orbit source: Preston date of fit: 2007 Dec 18 source of used astrometry: FASTT TMO MPC (via Astdys) number of used observations: 642 number of rejected observations: 82 time covered by the observations: 1903 Nov 20 - 2007 Dec 18 1 sigma uncertainty ellipse (major, minor, PA): 0.019, 0.015, 82° remarks: * orbital elements for (198) Ampella : Mean anomaly = 50.11748544 deg Arg. of pericenter = 88.63905800 deg Long. of node = 268.52774863 deg Inclination = 9.31011686 deg Eccentricity = 0.22793014 Semimajor axis = 2.45910251 AU Perihelion dist = 1.89859892 AU Mag: H = 8.25, G = 0.15 Epoch of elements : MJD 54467.76500000 TDT (2008 Jan 02.765) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 Jan 02 198 Ampella 18h 21.1m UT 12.1 3 9 8.197 22 5 39.342UCAC 39610922 0.0 11.8 57 12.0 1.434 0.679 -13.54 30.248 22.099 265.71 -22.92 18.3512 .70935 .49413 1.53655 -2.20978 0.00429 0.00093 2000 48.132850220071226.00000 88.639058268.527749 9.3101170.227930142.459102511.898598928.335 0.15 RATE 2.5558722 .0000000 .0000000 .0000000 .00000000 .00000000 .00000000 Meas 0.028 0.027 86.4 1.510 0.028 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2007 Dec 19, 04:00 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org