IOTA/IOTA-ES occultation update for (1306) Scythia / TYC 6788-00891-1 event on 2007 Jul 04, 13:31 UT Visible from SE Asia, Indonesia, Australia Summary ------- On 2007 Jul 04 UT, the 67 km diameter asteroid (1306) Scythia will occult a 12.3 mag star in the constellation Scorpius for observers along a path across SE Asia, Indonesia, Australia. In the case of an occultation, the combined light of the asteroid and the star will drop by 2.9 mag to 15.1 mag (the magnitude of the asteroid) for at most 6.5 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: 44 * date and approx. time of event: 2007 Jul 04, 13:19 - 2007 Jul 04, 13:38 UT * magnitude of target star: 12.3 * magnitude drop [mag]: 2.9 * estimated maximum duration [s]: 6.5 * Moon: 83 % sunlit, 85° distance * Sun: 143° distance * rough path description: SE Asia, Indonesia, Australia The occultation path -------------------- * approximate projected width [km]: 71 * 1 sigma uncertainty interval [path widths]: +/- 1.48 * 1 sigma uncertainty interval [seconds]: +/- 7.9 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .033 +/- .063) * 1 sigma uncertainty ellipse (major, minor, PA): ( .063", .033", 360° ) * approx speed of asteroid's shadow [km/s]: 10.3568 * website for maps: http://lunar-occultations.com/iota/asteroids/astrndx.htm http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 6788-00891-1 by 1306 Scythia on 2007 Jul 04 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 ... .. .. 52 0 0 .. .. .. .. .. .. ... .. .. ... .. .. 68 22 38 ... .. .. 67 3 17 51 0 0 13 38 36 1 139 17 67 44 3 66 22 20 69 43 46 ... .. .. 68 25 48 50 0 0 13 38 36 2 140 16 69 5 23 67 46 3 71 1 44 ... .. .. 69 45 5 49 0 0 13 38 35 3 141 15 70 23 36 69 6 26 72 16 52 ... .. .. 71 1 29 48 0 0 13 38 34 5 142 14 71 39 1 70 23 51 73 29 27 ... .. .. 72 15 17 47 0 0 13 38 33 6 143 13 72 51 53 71 38 34 74 39 42 69 49 13 73 26 41 46 0 0 13 38 31 7 143 12 74 2 28 72 50 50 75 47 51 71 4 7 74 35 57 45 0 0 13 38 29 9 144 10 75 10 57 74 0 53 76 54 5 72 16 35 75 43 16 44 0 0 13 38 27 10 145 9 76 17 32 75 8 56 77 58 35 73 26 52 76 48 48 43 0 0 13 38 24 11 146 8 77 22 23 76 15 9 79 1 30 74 35 9 77 52 42 42 0 0 13 38 22 12 147 7 78 25 40 77 19 41 80 2 58 75 41 38 78 55 8 41 0 0 13 38 18 14 147 6 79 27 31 78 22 43 81 3 8 76 46 27 79 56 13 40 0 0 13 38 15 15 148 5 80 28 4 79 24 21 82 2 7 77 49 45 80 56 5 39 0 0 13 38 11 16 149 4 81 27 25 80 24 43 83 0 0 78 51 41 81 54 49 38 0 0 13 38 7 17 149 3 82 25 41 81 23 56 83 56 53 79 52 21 82 52 33 37 0 0 13 38 3 19 150 1 83 22 57 82 22 6 84 52 53 80 51 53 83 49 20 36 0 0 13 37 58 20 150 0 84 19 20 83 19 19 85 48 4 81 50 22 84 45 18 35 0 0 13 37 53 21 151 -1 85 14 55 84 15 40 86 42 32 82 47 53 85 40 29 34 0 0 13 37 48 22 152 -2 86 9 45 85 11 14 87 36 19 83 44 33 86 35 0 33 0 0 13 37 42 24 152 -3 87 3 55 86 6 4 88 29 31 84 40 26 87 28 54 32 0 0 13 37 37 25 153 -4 87 57 30 87 0 17 89 22 12 85 35 36 88 22 14 31 0 0 13 37 31 26 153 -5 88 50 33 87 53 55 90 14 24 86 30 7 89 15 5 30 0 0 13 37 24 27 154 -6 89 43 8 88 47 3 91 6 13 87 24 5 90 7 31 29 0 0 13 37 18 28 154 -8 90 35 18 89 39 44 91 57 39 88 17 32 90 59 34 28 0 0 13 37 11 30 155 -9 91 27 7 90 32 1 92 48 48 89 10 31 91 51 17 27 0 0 13 37 4 31 155 -10 92 18 38 91 23 57 93 39 42 90 3 7 92 42 44 26 0 0 13 36 57 32 156 -11 93 9 53 92 15 36 94 30 23 90 55 23 93 33 58 25 0 0 13 36 49 33 156 -12 94 0 57 93 7 1 95 20 55 91 47 21 94 25 1 24 0 0 13 36 41 34 157 -13 94 51 50 93 58 14 96 11 21 92 39 5 95 15 57 23 0 0 13 36 33 36 158 -15 95 42 36 94 49 19 97 1 42 93 30 37 96 6 47 22 0 0 13 36 25 37 158 -16 96 33 19 95 40 17 97 52 1 94 22 0 96 57 34 21 0 0 13 36 16 38 159 -17 97 23 59 96 31 12 98 42 22 95 13 17 97 48 22 20 0 0 13 36 7 39 159 -18 98 14 40 97 22 5 99 32 46 96 4 30 98 39 11 19 0 0 13 35 58 40 160 -19 99 5 25 98 13 0 100 23 16 96 55 42 99 30 6 18 0 0 13 35 49 42 160 -20 99 56 15 99 4 0 101 13 53 97 46 56 100 21 8 17 0 0 13 35 39 43 161 -22 100 47 13 99 55 5 102 4 42 98 38 13 101 12 19 16 0 0 13 35 29 44 162 -23 101 38 22 100 46 19 102 55 44 99 29 37 102 3 43 15 0 0 13 35 19 45 162 -24 102 29 44 101 37 45 103 47 1 100 21 10 102 55 21 14 0 0 13 35 9 46 163 -25 103 21 21 102 29 25 104 38 36 101 12 54 103 47 16 13 0 0 13 34 58 48 164 -27 104 13 16 103 21 20 105 30 31 102 4 51 104 39 31 12 0 0 13 34 47 49 164 -28 105 5 31 104 13 34 106 22 49 102 57 5 105 32 8 11 0 0 13 34 36 50 165 -29 105 58 9 105 6 10 107 15 33 103 49 38 106 25 9 10 0 0 13 34 25 51 166 -30 106 51 13 105 59 9 108 8 45 104 42 31 107 18 38 9 0 0 13 34 13 52 167 -31 107 44 45 106 52 35 109 2 28 105 35 49 108 12 37 8 0 0 13 34 1 53 168 -33 108 38 48 107 46 29 109 56 45 106 29 33 109 7 9 7 0 0 13 33 49 55 169 -34 109 33 25 108 40 56 110 51 39 107 23 46 110 2 16 6 0 0 13 33 37 56 170 -35 110 28 39 109 35 58 111 47 12 108 18 32 110 58 3 5 0 0 13 33 24 57 171 -37 111 24 33 110 31 37 112 43 28 109 13 52 111 54 31 4 0 0 13 33 12 58 172 -38 112 21 9 111 27 58 113 40 31 110 9 51 112 51 45 3 0 0 13 32 59 59 173 -39 113 18 33 112 25 3 114 38 24 111 6 30 113 49 49 2 0 0 13 32 45 60 175 -40 114 16 47 113 22 56 115 37 10 112 3 55 114 48 45 1 0 0 13 32 32 61 176 -42 115 15 55 114 21 41 116 36 55 113 2 8 115 48 38 0 0 0 13 32 18 62 178 -43 116 16 0 115 21 21 117 37 41 114 1 12 116 49 32 - 1 0 0 13 32 4 63 180 -44 117 17 9 116 22 1 118 39 35 115 1 13 Latitude Latitude Latitude 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36 256 -70 -29 52 16 -30 30 39 -28 55 11 -31 27 10 -177 0 0 -30 11 40 13 21 16 35 256 -69 -29 52 28 -30 30 50 -28 55 22 -31 27 22 -176 0 0 -30 11 10 13 21 11 34 255 -68 -29 51 57 -30 30 20 -28 54 50 -31 26 53 -175 0 0 -30 9 58 13 21 5 33 255 -67 -29 50 44 -30 29 9 -28 53 36 -31 25 43 -174 0 0 -30 8 3 13 21 0 33 255 -66 -29 48 49 -30 27 15 -28 51 39 -31 23 52 -173 0 0 -30 5 27 13 20 55 32 254 -66 -29 46 12 -30 24 40 -28 48 59 -31 21 19 -172 0 0 -30 2 9 13 20 50 31 254 -65 -29 42 52 -30 21 22 -28 45 36 -31 18 5 -171 0 0 -29 58 8 13 20 45 30 253 -64 -29 38 50 -30 17 23 -28 41 29 -31 14 9 -170 0 0 -29 53 24 13 20 40 29 253 -63 -29 34 5 -30 12 41 -28 36 39 -31 9 32 -169 0 0 -29 47 57 13 20 35 29 253 -62 -29 28 36 -30 7 16 -28 31 5 -31 4 13 -168 0 0 -29 41 47 13 20 31 28 252 -61 -29 22 24 -30 1 8 -28 24 47 -30 58 11 -167 0 0 -29 34 54 13 20 26 27 252 -61 -29 15 29 -29 54 17 -28 17 44 -30 51 26 -166 0 0 -29 27 17 13 20 22 26 251 -60 -29 7 49 -29 46 43 -28 9 57 -30 43 59 -165 0 0 -29 18 56 13 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19 33 13 246 -47 -25 59 19 -26 40 13 -24 58 24 -27 40 26 -151 0 0 -26 0 14 13 19 31 13 245 -47 -25 39 39 -26 20 46 -24 38 25 -27 21 17 -150 0 0 -25 39 48 13 19 29 12 245 -46 -25 19 6 -26 0 26 -24 17 32 -27 1 16 -149 0 0 -25 18 27 13 19 27 11 244 -45 -24 57 39 -25 39 13 -23 55 44 -26 40 23 -148 0 0 -24 56 12 13 19 25 10 244 -44 -24 35 16 -25 17 5 -23 33 0 -26 18 35 -147 0 0 -24 33 1 13 19 23 9 243 -43 -24 11 58 -24 54 1 -23 9 19 -25 55 53 -146 0 0 -24 8 53 13 19 21 8 243 -42 -23 47 42 -24 30 1 -22 44 40 -25 32 16 -145 0 0 -23 43 48 13 19 20 7 243 -41 -23 22 29 -24 5 4 -22 19 2 -25 7 42 -144 0 0 -23 17 44 13 19 18 6 242 -40 -22 56 16 -23 39 8 -21 52 24 -24 42 10 -143 0 0 -22 50 40 13 19 17 5 242 -39 -22 29 3 -23 12 13 -21 24 46 -24 15 40 -142 0 0 -22 22 35 13 19 17 4 242 -38 -22 0 50 -22 44 17 -20 56 4 .. .. .. -141 0 0 -21 53 29 13 19 16 3 241 -37 -21 31 34 -22 15 20 -20 26 20 .. .. .. -140 0 0 -21 23 19 13 19 15 2 241 -36 -21 1 14 -21 45 20 -19 55 31 .. .. .. -139 0 0 -20 52 5 13 19 15 0 240 -35 -20 29 51 -21 14 16 .. .. .. .. .. .. Data for the target star ------------------------ * name: TYC 6788-00891-1 * constellation : Scorpius * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 16 07 56.7257 DE: -27 40 22.106 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .022, .061 ) * V mag [mag]: 12.3 * B mag [mag]: 12.2 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (1306) Scythia approx. diameter [km]: 67 approx. diameter ["]: .036 distance from Earth [AU]: 2.55300 * orbital information: orbit source: Preston date of fit: 2007 Jun 28 source of used astrometry: FASTT TMO MPC (via Astdys) number of used observations: 617 number of rejected observations: 31 time covered by the observations: 1930 Jul 29 - 2007 Jun 23 1 sigma uncertainty ellipse (major, minor, PA): 0.024, 0.017, 88° remarks: * orbital elements for (1306) Scythia : Mean anomaly = 210.48971100 deg Arg. of pericenter = 135.03748110 deg Long. of node = 274.44530302 deg Inclination = 14.93341139 deg Eccentricity = 0.09527454 Semimajor axis = 3.15204343 AU Perihelion dist = 2.85173395 AU Mag: H = 9.48, G = 0.15 Epoch of elements : MJD 54285.56300000 TDT (2007 Jul 04.563) ------ occelmnt file for Occult BEGIN ----------------------------------- 2007 Jul 04 1306 Scythia 13h 28.9m UT 12.3 16 7 56.726-27 40 22.11TYC 6788-00891-1 12.2 15.1 67 6.5 2.553 -1.115 13.62 117.569 -27.676 -21.14 22.88 13.4824 .22274 .24336 -4.30437 3.95530 0.00341 -0.00012 2000 209.5099392007 629.00000135.037481274.445303 14.9334110.095274543.152043432.851733959.715 0.15 RATE 1.7612290 .0000000 .0000000 .0000000 .00000000 .00000000 .00000000 Meas 0.063 0.033 359.9 2.480 0.054 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2007 Jun 29, 02:48 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org