IOTA/IOTA-ES occultation update for (687) Tinette / TYC 7423-01638-1 event on 2012 Sep 16, 17:27 UT Visible from SW Asia, Africa Summary ------- On 2012 Sep 16 UT, the 25 km diameter asteroid (687) Tinette will occult a 9.6 mag star in the constellation Sagittarius for observers along a path across SW Asia, Africa. In the case of an occultation, the combined light of the asteroid and the star will drop by 6.4 mag to 16.0 mag (the magnitude of the asteroid) for at most 2.9 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: 26 * date and approx. time of event: 2012 Sep 16, 17:26 - 2012 Sep 16, 17:38 UT * geocentric midpoint of event [JD]: 2456187.2275375 * magnitude of target star: 9.6 * magnitude drop [mag]: 6.4 * estimated maximum duration [s]: 2.9 * Moon: 1 % sunlit, 103° distance * Sun: 112° distance * rough path description: SW Asia, Africa The occultation path -------------------- * approximate projected width [km]: 27 * 1 sigma uncertainty interval [path widths]: +/- 2.57 * 1 sigma uncertainty interval [seconds]: +/- 7.0 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .053 +/- .044) * 1 sigma uncertainty ellipse (major, minor, PA): ( .054", .043", 76° ) * approx speed of asteroid's shadow [km/s]: 8.8896 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 7423-01638-1 by 687 Tinette on 2012 Sep 16 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 36 2 18 59 0 0 17 38 40 0 186 -14 36 16 22 35 48 13 37 28 34 34 35 47 35 49 33 58 0 0 17 38 40 1 186 -14 36 3 13 35 35 52 37 13 25 34 25 27 35 36 45 57 0 0 17 38 40 2 186 -15 35 50 4 35 23 27 36 58 23 34 14 55 35 23 55 56 0 0 17 38 39 3 186 -15 35 36 53 35 10 57 36 43 25 34 4 11 35 11 1 55 0 0 17 38 38 4 185 -15 35 23 39 34 58 22 36 28 33 33 53 16 34 58 4 54 0 0 17 38 37 5 185 -16 35 10 25 34 45 43 36 13 45 33 42 11 34 45 4 53 0 0 17 38 36 6 185 -16 34 57 8 34 33 1 35 59 0 33 30 56 34 32 1 52 0 0 17 38 34 7 185 -16 34 43 48 34 20 14 35 44 19 33 19 31 34 18 55 51 0 0 17 38 32 8 185 -17 34 30 27 34 7 22 35 29 40 33 7 58 34 5 45 50 0 0 17 38 30 9 185 -17 34 17 3 33 54 27 35 15 2 32 56 16 33 52 32 49 0 0 17 38 28 10 184 -17 34 3 36 33 41 27 35 0 27 32 44 26 33 39 15 48 0 0 17 38 25 11 184 -18 33 50 7 33 28 23 34 45 52 32 32 27 33 25 55 47 0 0 17 38 22 12 184 -18 33 36 35 33 15 15 34 31 18 32 20 21 33 12 31 46 0 0 17 38 19 13 184 -18 33 22 59 33 2 2 34 16 43 32 8 7 32 59 2 45 0 0 17 38 16 14 184 -18 33 9 20 32 48 45 34 2 9 31 55 45 32 45 30 44 0 0 17 38 12 15 183 -19 32 55 37 32 35 22 33 47 34 31 43 15 32 31 53 43 0 0 17 38 9 16 183 -19 32 41 50 32 21 55 33 32 57 31 30 37 32 18 11 42 0 0 17 38 5 17 183 -19 32 28 0 32 8 23 33 18 20 31 17 52 32 4 25 41 0 0 17 38 1 19 183 -19 32 14 5 31 54 45 33 3 40 31 4 59 31 50 33 40 0 0 17 37 56 20 183 -19 32 0 5 31 41 2 32 48 58 30 51 58 31 36 36 39 0 0 17 37 51 21 182 -19 31 46 0 31 27 13 32 34 13 30 38 49 31 22 34 38 0 0 17 37 47 22 182 -20 31 31 50 31 13 18 32 19 25 30 25 32 31 8 26 37 0 0 17 37 41 23 182 -20 31 17 35 30 59 16 32 4 34 30 12 7 30 54 12 36 0 0 17 37 36 24 182 -20 31 3 14 30 45 9 31 49 39 29 58 34 30 39 51 35 0 0 17 37 30 25 181 -20 30 48 47 30 30 54 31 34 39 29 44 52 30 25 23 34 0 0 17 37 25 26 181 -20 30 34 14 30 16 33 31 19 35 29 31 1 30 10 49 33 0 0 17 37 19 27 181 -20 30 19 34 30 2 4 31 4 26 29 17 1 29 56 7 32 0 0 17 37 12 28 181 -20 30 4 46 29 47 27 30 49 11 29 2 52 29 41 18 31 0 0 17 37 6 29 180 -20 29 49 52 29 32 43 30 33 51 28 48 34 29 26 20 30 0 0 17 36 59 30 180 -20 29 34 49 29 17 50 30 18 24 28 34 6 29 11 14 29 0 0 17 36 52 31 180 -20 29 19 39 29 2 49 30 2 50 28 19 27 28 55 59 28 0 0 17 36 45 32 180 -20 29 4 20 28 47 38 29 47 9 28 4 39 28 40 35 27 0 0 17 36 38 33 179 -20 28 48 52 28 32 18 29 31 20 27 49 39 28 25 2 26 0 0 17 36 30 34 179 -20 28 33 15 28 16 49 29 15 24 27 34 28 28 9 18 25 0 0 17 36 22 35 179 -20 28 17 27 28 1 8 28 59 18 27 19 6 27 53 24 24 0 0 17 36 14 35 178 -20 28 1 30 27 45 17 28 43 4 27 3 32 27 37 19 23 0 0 17 36 6 36 178 -20 27 45 22 27 29 15 28 26 40 26 47 46 27 21 2 22 0 0 17 35 58 37 178 -20 27 29 2 27 13 2 28 10 6 26 31 47 27 4 33 21 0 0 17 35 49 38 177 -20 27 12 31 26 56 36 27 53 21 26 15 34 26 47 52 20 0 0 17 35 40 39 177 -20 26 55 47 26 39 57 27 36 25 25 59 8 26 30 58 19 0 0 17 35 31 40 176 -20 26 38 51 26 23 5 27 19 17 25 42 27 26 13 50 18 0 0 17 35 22 41 176 -20 26 21 41 26 5 59 27 1 56 25 25 32 25 56 28 17 0 0 17 35 13 42 176 -19 26 4 17 25 48 38 26 44 23 25 8 21 25 38 51 16 0 0 17 35 3 43 175 -19 25 46 38 25 31 3 26 26 36 24 50 53 25 20 58 15 0 0 17 34 53 44 175 -19 25 28 44 25 13 12 26 8 34 24 33 10 25 2 49 14 0 0 17 34 43 45 174 -19 25 10 34 24 55 4 25 50 17 24 15 8 24 44 23 13 0 0 17 34 33 46 174 -19 24 52 7 24 36 39 25 31 45 23 56 49 24 25 40 12 0 0 17 34 23 47 173 -18 24 33 23 24 17 57 25 12 56 23 38 11 24 6 38 11 0 0 17 34 12 48 172 -18 24 14 20 23 58 55 24 53 49 23 19 13 23 47 16 10 0 0 17 34 1 49 172 -18 23 54 58 23 39 35 24 34 25 22 59 54 23 27 35 9 0 0 17 33 51 50 171 -18 23 35 16 23 19 53 24 14 41 22 40 14 23 7 32 8 0 0 17 33 39 51 170 -17 23 15 13 22 59 51 23 54 38 22 20 12 22 47 8 7 0 0 17 33 28 52 170 -17 22 54 49 22 39 26 23 34 13 21 59 47 22 26 20 6 0 0 17 33 17 53 169 -17 22 34 1 22 18 38 23 13 27 21 38 58 22 5 8 5 0 0 17 33 5 54 168 -16 22 12 50 21 57 26 22 52 18 21 17 43 21 43 31 4 0 0 17 32 53 54 167 -16 21 51 14 21 35 48 22 30 45 20 56 2 21 21 28 3 0 0 17 32 41 55 166 -16 21 29 11 21 13 44 22 8 46 20 33 53 20 58 57 2 0 0 17 32 29 56 165 -15 21 6 42 20 51 12 21 46 22 20 11 16 20 35 58 1 0 0 17 32 17 57 164 -15 20 43 43 20 28 11 21 23 30 19 48 8 20 12 28 0 0 0 17 32 5 58 163 -15 20 20 15 20 4 40 21 0 9 19 24 29 19 48 26 - 1 0 0 17 31 52 59 162 -14 19 56 15 19 40 37 20 36 17 19 0 17 19 23 52 - 2 0 0 17 31 39 59 161 -14 19 31 42 19 16 0 20 11 54 18 35 30 18 58 42 - 3 0 0 17 31 26 60 159 -13 19 6 35 18 50 49 19 46 58 18 10 8 18 32 57 - 4 0 0 17 31 13 61 158 -13 18 40 52 18 25 1 19 21 26 17 44 7 18 6 33 - 5 0 0 17 31 0 62 156 -12 18 14 30 17 58 34 18 55 18 17 17 26 17 39 28 - 6 0 0 17 30 47 62 155 -12 17 47 29 17 31 27 18 28 31 16 50 4 17 11 42 - 7 0 0 17 30 33 63 153 -11 17 19 46 17 3 37 18 1 4 16 21 57 16 43 11 - 8 0 0 17 30 20 64 151 -11 16 51 18 16 35 3 17 32 54 15 53 5 16 13 54 - 9 0 0 17 30 6 64 150 -10 16 22 5 16 5 42 17 3 59 15 23 24 15 43 47 -10 0 0 17 29 52 65 148 -10 15 52 2 15 35 31 16 34 17 14 52 52 Latitude Latitude Latitude Latitude 14 0 0 -13 14 27 17 29 6 66 140 -8 -13 29 37 -12 59 12 -14 46 45 -11 39 54 13 0 0 -14 58 42 17 28 41 67 136 -7 -15 13 22 -14 44 0 -16 27 53 -13 27 29 12 0 0 -16 37 27 17 28 16 67 132 -6 -16 51 38 -16 23 14 -18 3 44 -15 9 19 11 0 0 -18 11 1 17 27 53 67 128 -5 -18 24 45 -17 57 15 -19 34 37 -16 45 44 10 0 0 -19 39 44 17 27 30 67 124 -4 -19 53 3 -19 26 23 -21 0 50 -18 17 4 9 0 0 -21 3 53 17 27 9 67 120 -3 -21 16 49 -20 50 55 -22 22 40 -19 43 40 8 0 0 -22 23 45 17 26 48 67 116 -2 -22 36 19 -22 11 9 -23 40 22 -21 5 49 7 0 0 -23 39 36 17 26 28 67 113 -1 -23 51 50 -23 27 20 -24 54 12 -22 23 46 Uncertainty in time = +/- 8 secs Prediction of 2012 Aug 26.0 Data for the target star ------------------------ * name: TYC 7423-01638-1 * constellation : Sagittarius * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 19 17 35.5812 DE: -30 37 55.325 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .023, .027 ) * V mag [mag]: 9.6 * B mag [mag]: 10.4 * Diameter [mas]: 0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (687) Tinette approx. diameter [km]: 25 approx. diameter ["]: .019 distance from Earth [AU]: 1.82200 * orbital information: orbit source: Preston date of fit: 2012 Aug 25 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 752 number of rejected observations: 30 time covered by the observations: 1918 Sep 02 - 2012 Aug 12 1 sigma uncertainty ellipse (major, minor, PA): 0.049, 0.034, 73° remarks: * orbital elements for (687) Tinette : Mean anomaly = 310.37037259 deg Arg. of pericenter = 53.12401461 deg Long. of node = 334.38711176 deg Inclination = 14.86411076 deg Eccentricity = 0.27100474 Semimajor axis = 2.72302547 AU Perihelion dist = 1.98507265 AU Mag: H = 11.48, G = 0.15 Epoch of elements : MJD 56186.72800000 TDT (2012 Sep 16.728) ------ occelmnt file for Occult BEGIN ----------------------------------- 2012 Sep 16 687 Tinette 17h 27.7m UT 9.6 19 17 35.581-30 37 55.32TYC 7423-01638-1 10.4 16.0 25 2.9 1.822 0.830 21.72 31.4215 -30.638 -83.26 2.28 17.4609 -0.34243 0.16895 2.21536 4.50196 0.00504 0.00099 2000 308.8946242012 910.00000 53.124015334.387112 14.8641110.27100474 2.7230255 1.985072711.7 5.00.15 RATE 2.1934440 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.054 0.043 76 3.57 0.049 0 0 2-5 056165.0020120916_1638-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2012 Aug 25, 22:52 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org