IOTA/IOTA-ES occultation update for (4547) Massachusetts / TYC 7451-01272-1 event on 2012 Sep 27, 19:04 UT Visible from Africa Summary ------- On 2012 Sep 27 UT, the 32 km diameter asteroid (4547) Massachusetts will occult a 9.4 mag star in the constellation Sagittarius for observers along a path across Africa. In the case of an occultation, the combined light of the asteroid and the star will drop by 6.8 mag to 16.2 mag (the magnitude of the asteroid) for at most 2.6 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: 28 * date and approx. time of event: 2012 Sep 27, 19:03 - 2012 Sep 27, 19:13 UT * geocentric midpoint of event [JD]: 2456198.29496667 * magnitude of target star: 9.4 * magnitude drop [mag]: 6.8 * estimated maximum duration [s]: 2.6 * Moon: 94 % sunlit, 47° distance * Sun: 108° distance * rough path description: Africa Additional comments ------------------- close double star The occultation path -------------------- * approximate projected width [km]: 33 * 1 sigma uncertainty interval [path widths]: +/- 2.42 * 1 sigma uncertainty interval [seconds]: +/- 6.0 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .058 +/- .043) * 1 sigma uncertainty ellipse (major, minor, PA): ( .059", .042", 74° ) * approx speed of asteroid's shadow [km/s]: 12.3458 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 7451-01272-1 by 4547 Massachusetts on 2012 Sep 27 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 21 47 46 52 0 0 19 13 4 1 194 -26 22 2 35 21 32 57 23 14 22 20 21 16 21 23 33 51 0 0 19 13 4 2 194 -27 21 38 2 21 9 3 22 48 14 19 58 57 20 59 58 50 0 0 19 13 4 3 194 -27 21 14 9 20 45 47 22 22 50 19 37 9 20 36 57 49 0 0 19 13 3 4 193 -27 20 50 51 20 23 4 21 58 7 19 15 51 20 14 29 48 0 0 19 13 2 5 193 -28 20 28 7 20 0 52 21 34 3 18 54 59 19 52 31 47 0 0 19 13 2 6 193 -28 20 5 53 19 39 10 21 10 33 18 34 31 19 31 0 46 0 0 19 13 1 7 192 -28 19 44 7 19 17 54 20 47 36 18 14 26 19 9 55 45 0 0 19 12 59 8 192 -29 19 22 48 18 57 2 20 25 9 17 54 41 18 49 12 44 0 0 19 12 58 9 192 -29 19 1 52 18 36 33 20 3 9 17 35 15 18 28 51 43 0 0 19 12 57 10 192 -29 18 41 18 18 16 24 19 41 34 17 16 7 18 8 49 42 0 0 19 12 55 11 191 -29 18 21 5 17 56 34 19 20 23 16 57 14 17 49 6 41 0 0 19 12 53 12 191 -29 18 1 10 17 37 2 18 59 34 16 38 36 17 29 39 40 0 0 19 12 51 13 191 -30 17 41 33 17 17 46 18 39 5 16 20 12 17 10 28 39 0 0 19 12 49 14 191 -30 17 22 11 16 58 44 18 18 54 16 1 59 16 51 30 38 0 0 19 12 46 15 190 -30 17 3 4 16 39 56 17 59 0 15 43 57 16 32 45 37 0 0 19 12 44 16 190 -30 16 44 9 16 21 20 17 39 21 15 26 5 16 14 12 36 0 0 19 12 41 17 190 -30 16 25 27 16 2 56 17 19 57 15 8 22 15 55 49 35 0 0 19 12 38 18 190 -30 16 6 56 15 44 41 17 0 46 14 50 47 15 37 35 34 0 0 19 12 35 19 190 -31 15 48 35 15 26 35 16 41 47 14 33 19 15 19 30 33 0 0 19 12 32 20 189 -31 15 30 23 15 8 38 16 22 59 14 15 57 15 1 33 32 0 0 19 12 29 21 189 -31 15 12 18 14 50 47 16 4 20 13 58 41 14 43 42 31 0 0 19 12 25 22 189 -31 14 54 21 14 33 3 15 45 51 13 41 29 14 25 57 30 0 0 19 12 22 23 189 -31 14 36 30 14 15 25 15 27 29 13 24 21 14 8 17 29 0 0 19 12 18 24 189 -31 14 18 44 13 57 51 15 9 14 13 7 15 13 50 41 28 0 0 19 12 14 25 188 -31 14 1 2 13 40 20 14 51 5 12 50 12 13 33 9 27 0 0 19 12 10 26 188 -31 13 43 24 13 22 53 14 33 1 12 33 11 13 15 39 26 0 0 19 12 5 27 188 -31 13 25 49 13 5 28 14 15 2 12 16 10 12 58 11 25 0 0 19 12 1 28 188 -31 13 8 17 12 48 5 13 57 6 11 59 10 12 40 44 24 0 0 19 11 56 29 188 -31 12 50 45 12 30 43 13 39 13 11 42 9 12 23 18 23 0 0 19 11 52 30 187 -31 12 33 15 12 13 21 13 21 21 11 25 7 12 5 51 22 0 0 19 11 47 31 187 -31 12 15 44 11 55 58 13 3 32 11 8 4 11 48 24 21 0 0 19 11 42 32 187 -31 11 58 13 11 38 34 12 45 42 10 50 57 11 30 54 20 0 0 19 11 36 33 187 -30 11 40 40 11 21 8 12 27 53 10 33 48 11 13 23 19 0 0 19 11 31 34 186 -30 11 23 5 11 3 40 12 10 2 10 16 35 10 55 48 18 0 0 19 11 25 35 186 -30 11 5 28 10 46 8 11 52 10 9 59 17 10 38 10 17 0 0 19 11 20 36 186 -30 10 47 47 10 28 32 11 34 16 9 41 55 10 20 27 16 0 0 19 11 14 37 186 -30 10 30 1 10 10 52 11 16 18 9 24 27 10 2 39 15 0 0 19 11 8 38 186 -30 10 12 11 9 53 7 10 58 17 9 6 52 9 44 45 14 0 0 19 11 2 40 185 -29 9 54 16 9 35 15 10 40 11 8 49 11 9 26 45 13 0 0 19 10 56 41 185 -29 9 36 14 9 17 17 10 22 0 8 31 21 9 8 38 12 0 0 19 10 49 42 185 -29 9 18 5 8 59 11 10 3 43 8 13 23 8 50 23 11 0 0 19 10 43 43 184 -29 8 59 48 8 40 58 9 45 20 7 55 17 8 31 59 10 0 0 19 10 36 44 184 -28 8 41 23 8 22 35 9 26 49 7 37 0 8 13 26 9 0 0 19 10 29 45 184 -28 8 22 49 8 4 3 9 8 10 7 18 33 7 54 43 8 0 0 19 10 22 46 184 -28 8 4 5 7 45 21 8 49 22 6 59 54 7 35 49 7 0 0 19 10 15 47 183 -28 7 45 11 7 26 27 8 30 24 6 41 3 7 16 43 6 0 0 19 10 8 48 183 -27 7 26 4 7 7 22 8 11 16 6 22 0 6 57 25 5 0 0 19 10 1 49 182 -27 7 6 46 6 48 4 7 51 56 6 2 42 6 37 53 4 0 0 19 9 53 50 182 -26 6 47 14 6 28 32 7 32 24 5 43 10 6 18 7 3 0 0 19 9 46 51 182 -26 6 27 29 6 8 46 7 12 39 5 23 23 5 58 6 2 0 0 19 9 38 52 181 -26 6 7 28 5 48 44 6 52 41 5 3 19 5 37 49 1 0 0 19 9 30 53 181 -25 5 47 11 5 28 27 6 32 27 4 42 58 5 17 15 0 0 0 19 9 22 54 180 -25 5 26 38 5 7 52 6 11 57 4 22 19 4 56 23 - 1 0 0 19 9 14 55 180 -25 5 5 47 4 46 58 5 51 11 4 1 20 4 35 12 - 2 0 0 19 9 6 56 179 -24 4 44 37 4 25 46 5 30 7 3 40 1 4 13 40 - 3 0 0 19 8 58 57 179 -24 4 23 7 4 4 13 5 8 44 3 18 21 3 51 47 - 4 0 0 19 8 50 58 178 -23 4 1 16 3 42 18 4 47 1 2 56 18 3 29 32 - 5 0 0 19 8 41 59 177 -23 3 39 2 3 20 1 4 24 57 2 33 51 3 6 53 - 6 0 0 19 8 33 60 176 -22 3 16 26 2 57 20 4 2 31 2 10 58 2 43 49 - 7 0 0 19 8 24 61 176 -22 2 53 24 2 34 13 3 39 41 1 47 40 2 20 18 - 8 0 0 19 8 15 61 175 -21 2 29 56 2 10 40 3 16 25 1 23 53 1 56 20 - 9 0 0 19 8 6 62 174 -21 2 6 1 1 46 38 2 52 44 0 59 37 1 31 52 -10 0 0 19 7 57 63 173 -20 1 41 36 1 22 7 2 28 35 0 34 50 1 6 53 -11 0 0 19 7 48 64 172 -20 1 16 41 0 57 5 2 3 56 0 9 30 0 41 22 -12 0 0 19 7 39 65 171 -19 0 51 13 0 31 30 1 38 46 - 0 16 24 0 15 16 -13 0 0 19 7 30 66 169 -18 0 25 11 0 5 20 1 13 4 - 0 42 54 - 0 11 26 -14 0 0 19 7 20 67 168 -18 - 0 1 27 - 0 21 27 0 46 47 - 1 10 2 - 0 38 47 -15 0 0 19 7 11 68 166 -17 - 0 28 42 - 0 48 52 0 19 53 - 1 37 51 - 1 6 48 -16 0 0 19 7 1 69 165 -17 - 0 56 38 - 1 16 58 - 0 7 39 - 2 6 22 - 1 35 32 -17 0 0 19 6 51 69 163 -16 - 1 25 17 - 1 45 47 - 0 35 51 - 2 35 38 - 2 5 1 -18 0 0 19 6 42 70 161 -15 - 1 54 40 - 2 15 22 - 1 4 47 - 3 5 42 - 2 35 18 -19 0 0 19 6 32 71 159 -15 - 2 24 51 - 2 45 45 - 1 34 28 - 3 36 35 Latitude Latitude Latitude Latitude - 4 0 0 -21 39 28 19 6 5 73 152 -13 -21 58 56 -21 19 55 -23 32 16 -19 44 22 - 5 0 0 -23 25 19 19 5 47 74 146 -12 -23 44 11 -23 6 24 -25 14 39 -21 33 53 - 6 0 0 -25 5 39 19 5 30 74 141 -11 -25 23 56 -24 47 18 -26 51 42 -23 17 40 - 7 0 0 -26 40 45 19 5 13 75 134 -9 -26 58 30 -26 22 57 -28 23 43 -24 56 0 - 8 0 0 -28 10 56 19 4 57 75 128 -8 -28 28 11 -27 53 38 -29 51 0 -26 29 13 - 9 0 0 -29 36 29 19 4 42 75 122 -7 -29 53 15 -29 19 40 -31 13 49 -27 57 37 - 10 0 0 -30 57 39 19 4 27 75 117 -6 -31 13 59 -30 41 17 -32 32 25 -29 21 29 - 11 0 0 -32 14 43 19 4 13 75 111 -5 -32 30 37 -31 58 47 -33 47 3 -30 41 4 - 12 0 0 -33 27 55 19 4 0 74 107 -4 -33 43 25 -33 12 23 -34 57 58 -31 56 38 - 13 0 0 -34 37 28 19 3 47 74 102 -3 -34 52 36 -34 22 18 -36 5 22 -33 8 26 - 14 0 0 -35 43 35 19 3 34 73 99 -2 -35 58 22 -35 28 47 -37 9 27 -34 16 39 - 15 0 0 -36 46 28 19 3 22 72 96 -1 -37 0 54 -36 32 0 -38 10 25 -35 21 31 - 16 0 0 -37 46 18 19 3 11 72 93 0 -38 0 25 -37 32 8 -39 8 26 -36 23 14 Uncertainty in time = +/- 7 secs Prediction of 2012 Aug 7.0 Data for the target star ------------------------ * name: TYC 7451-01272-1 * constellation : Sagittarius * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 19 56 52.9245 DE: -36 22 41.612 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .027, .027 ) * V mag [mag]: 9.4 * B mag [mag]: 9.7 * Diameter [mas]: 0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (4547) Massachusetts approx. diameter [km]: 32 approx. diameter ["]: .021 distance from Earth [AU]: 2.07700 * orbital information: orbit source: Preston date of fit: 2012 Aug 06 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 747 number of rejected observations: 19 time covered by the observations: 1909 Jan 29 - 2012 Jun 24 1 sigma uncertainty ellipse (major, minor, PA): 0.053, 0.032, 70° remarks: * orbital elements for (4547) Massachusetts : Mean anomaly = 285.76045514 deg Arg. of pericenter = 38.28546720 deg Long. of node = 358.37764092 deg Inclination = 18.00392937 deg Eccentricity = 0.06851786 Semimajor axis = 2.61330808 AU Perihelion dist = 2.43424981 AU Mag: H = 11.55, G = 0.15 Epoch of elements : MJD 56197.79500000 TDT (2012 Sep 27.795) ------ occelmnt file for Occult BEGIN ----------------------------------- 2012 Sep 27 4547 Massachusetts 19h 4.8m UT 9.4 19 56 52.925-36 22 41.61TYC 7451-01272-1 9.7 16.2 32 2.6 2.077 1.047 26.66 6.0595 -36.386 -108.50 -2.02 19.0792 -0.22679 0.10738 2.98203 6.29802 0.00511 0.00154 2000 283.9418672012 920.00000 38.285467358.377641 18.0039290.06851786 2.6133081 2.434249811.5 5.00.15 RATE 2.3330190 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.059 0.042 74 3.42 0.051 0 0-5-2 056146.0020120927_1272-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2012 Aug 06, 21:09 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org