IOTA/IOTA-ES occultation update for (1939) Loretta / TYC 6336-01997-1 event on 2012 Nov 29, 14:07 UT Visible from India Summary ------- On 2012 Nov 29 UT, the 29 km diameter asteroid (1939) Loretta will occult a 10.2 mag star in the constellation Capricornus 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 6.6 mag to 16.8 mag (the magnitude of the asteroid) for at most 0.8 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: 22 * date and approx. time of event: 2012 Nov 29, 14:09 - 2012 Nov 29, 14:10 UT * geocentric midpoint of event [JD]: 2456261.08868333 * magnitude of target star: 10.2 * magnitude drop [mag]: 6.6 * estimated maximum duration [s]: 0.8 * Moon: 99 % sunlit, 135° distance * Sun: 56° distance * rough path description: India Additional comments ------------------- 17" double star The occultation path -------------------- * approximate projected width [km]: 31 * 1 sigma uncertainty interval [path widths]: +/- 3.11 * 1 sigma uncertainty interval [seconds]: +/- 3.0 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .044 +/- .034) * 1 sigma uncertainty ellipse (major, minor, PA): ( .044", .034", 86° ) * approx speed of asteroid's shadow [km/s]: 34.3774 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 6336-01997-1 by 1939 Loretta on 2012 Nov 29 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 51 0 0 11 30 41 14 9 23 49 220 -1 11 21 28 11 39 54 10 24 26 12 37 29 52 0 0 11 56 19 14 9 25 48 220 -2 11 47 6 12 5 33 10 49 58 13 3 14 53 0 0 12 22 12 14 9 28 47 221 -3 12 12 57 12 31 26 11 15 44 13 29 13 54 0 0 12 48 17 14 9 31 46 222 -4 12 39 2 12 57 33 11 41 43 13 55 24 55 0 0 13 14 35 14 9 34 45 222 -5 13 5 19 13 23 51 12 7 55 14 21 48 56 0 0 13 41 4 14 9 36 44 223 -6 13 31 47 13 50 21 12 34 18 14 48 23 57 0 0 14 7 44 14 9 39 43 224 -7 13 58 27 14 17 2 13 0 53 15 15 9 58 0 0 14 34 34 14 9 41 42 224 -8 14 25 16 14 43 53 13 27 38 15 42 5 59 0 0 15 1 34 14 9 44 41 225 -9 14 52 15 15 10 54 13 54 32 16 9 10 60 0 0 15 28 43 14 9 46 40 226 -10 15 19 23 15 38 3 14 21 36 16 36 24 61 0 0 15 55 59 14 9 49 39 226 -11 15 46 39 16 5 21 14 48 48 17 3 45 62 0 0 16 23 23 14 9 51 38 227 -13 16 14 2 16 32 45 15 16 7 17 31 14 63 0 0 16 50 53 14 9 53 37 227 -14 16 41 32 17 0 16 15 43 33 17 58 48 64 0 0 17 18 29 14 9 55 36 228 -15 17 9 7 17 27 52 16 11 5 18 26 28 65 0 0 17 46 10 14 9 58 35 228 -16 17 36 47 17 55 33 16 38 42 18 54 13 66 0 0 18 13 55 14 10 0 34 229 -17 18 4 32 18 23 19 17 6 23 19 22 1 67 0 0 18 41 43 14 10 2 33 229 -18 18 32 19 18 51 7 17 34 8 19 49 53 68 0 0 19 9 34 14 10 4 32 230 -19 19 0 10 19 18 58 18 1 56 20 17 46 69 0 0 19 37 26 14 10 6 31 230 -20 19 28 2 19 46 51 18 29 46 20 45 42 70 0 0 20 5 20 14 10 8 30 231 -21 19 55 55 20 14 45 18 57 37 21 13 37 71 0 0 20 33 13 14 10 9 29 231 -22 20 23 48 20 42 39 19 25 28 21 41 33 72 0 0 21 1 6 14 10 11 28 232 -23 20 51 41 21 10 32 19 53 19 22 9 28 73 0 0 21 28 58 14 10 13 27 232 -24 21 19 32 21 38 24 20 21 10 22 37 21 74 0 0 21 56 47 14 10 14 26 233 -25 21 47 21 22 6 13 20 48 58 23 5 12 75 0 0 22 24 34 14 10 16 25 233 -26 22 15 8 22 34 0 21 16 44 23 32 59 76 0 0 22 52 17 14 10 17 24 234 -27 22 42 51 23 1 43 21 44 26 24 0 42 77 0 0 23 19 55 14 10 19 23 234 -28 23 10 29 23 29 22 22 12 4 24 28 21 78 0 0 23 47 28 14 10 20 22 235 -29 23 38 2 23 56 55 22 39 37 24 55 55 79 0 0 24 14 56 14 10 21 21 235 -30 24 5 30 24 24 22 23 7 5 25 23 22 80 0 0 24 42 17 14 10 23 20 235 -31 24 32 51 24 51 43 23 34 27 25 50 42 81 0 0 25 9 30 14 10 24 19 236 -32 25 0 5 25 18 57 24 1 41 26 17 54 82 0 0 25 36 36 14 10 25 18 236 -33 25 27 11 25 46 2 24 28 48 26 44 59 83 0 0 26 3 33 14 10 26 17 237 -34 25 54 8 26 12 59 24 55 47 27 11 54 84 0 0 26 30 21 14 10 27 16 237 -35 26 20 56 26 39 46 25 22 36 27 38 40 85 0 0 26 56 59 14 10 28 15 238 -36 26 47 34 27 6 24 25 49 16 28 5 16 86 0 0 27 23 26 14 10 29 14 238 -37 27 14 1 27 32 51 26 15 46 28 31 40 87 0 0 27 49 42 14 10 30 13 239 -38 27 40 18 27 59 6 26 42 5 28 57 54 88 0 0 28 15 46 14 10 30 12 239 -39 28 6 23 28 25 10 27 8 12 29 23 55 89 0 0 28 41 38 14 10 31 11 240 -40 28 32 15 28 51 2 27 34 7 29 49 43 90 0 0 29 7 17 14 10 32 10 240 -41 28 57 55 29 16 40 27 59 50 30 15 19 91 0 0 29 32 43 14 10 32 9 241 -41 29 23 21 29 42 5 28 25 19 30 40 41 92 0 0 29 57 55 14 10 33 8 241 -42 29 48 33 30 7 17 28 50 35 31 5 48 93 0 0 30 22 52 14 10 33 7 242 -43 30 13 31 30 32 13 29 15 37 31 30 41 94 0 0 30 47 34 14 10 33 6 242 -44 30 38 14 30 56 55 29 40 24 31 55 19 95 0 0 31 12 1 14 10 34 5 243 -45 31 2 42 31 21 22 30 4 56 32 19 41 96 0 0 31 36 13 14 10 34 4 243 -46 31 26 54 31 45 32 30 29 12 32 43 47 97 0 0 32 0 8 14 10 34 3 244 -47 31 50 50 32 9 26 .. .. .. 33 7 37 98 0 0 32 23 46 14 10 34 2 244 -47 32 14 29 32 33 4 .. .. .. 33 31 10 99 0 0 32 47 8 14 10 34 1 245 -48 32 37 51 32 56 25 .. .. .. 33 54 26 100 0 0 33 10 12 14 10 34 0 245 -49 33 0 56 33 19 28 .. .. .. .. .. .. Uncertainty in time = +/- 3 secs Prediction of 2012 Nov 16.0 Data for the target star ------------------------ * name: TYC 6336-01997-1 * constellation : Capricornus * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 20 22 21.0568 DE: -20 13 34.931 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .037, .030 ) * V mag [mag]: 10.2 * B mag [mag]: 10.9 * Diameter [mas]: 0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (1939) Loretta approx. diameter [km]: 29 approx. diameter ["]: .011 distance from Earth [AU]: 3.50200 * orbital information: orbit source: Preston date of fit: 2012 Oct 07 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 1211 number of rejected observations: 52 time covered by the observations: 1939 Mar 17 - 2012 Jul 18 1 sigma uncertainty ellipse (major, minor, PA): 0.024, 0.016, 77° remarks: * orbital elements for (1939) Loretta : Mean anomaly = 73.00210340 deg Arg. of pericenter = 190.64109163 deg Long. of node = 40.41718193 deg Inclination = 0.90730965 deg Eccentricity = 0.12738177 Semimajor axis = 3.12162980 AU Perihelion dist = 2.72399108 AU Mag: H = 11.02, G = 0.15 Epoch of elements : MJD 56260.58900000 TDT (2012 Nov 29.589) ------ occelmnt file for Occult BEGIN ----------------------------------- 2012 Nov 29 1939 Loretta 14h 7.7m UT 10.2 20 22 21.057-20 13 34.93TYC 6336-01997-1 10.9 16.8 29 0.8 3.502 3.361 11.71 24.7974 -20.229 -34.80 -21.60 14.1284 -0.08871 0.35894 18.83544 4.66087 0.00479 0.00109 2000 72.89684720121129.00000190.641092 40.417182 0.9073100.12738177 3.1216298 2.723991110.8 5.00.15 RATE 1.7870300 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.044 0.034 86 4.11 0.035 0 0-2-1 056247.0020121129_1997-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2012 Oct 07, 20:44 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org