IOTA/IOTA-ES occultation update for (428) Monachia / TYC 6906-01268-1 event on 2012 Nov 23, 15:59 UT Visible from Arabia, SW Asia Summary ------- On 2012 Nov 23 UT, the 22 km diameter asteroid (428) Monachia will occult a 9.8 mag star in the constellation Capricornus for observers along a path across Arabia, SW Asia. In the case of an occultation, the combined light of the asteroid and the star will drop by 6.8 mag to 16.6 mag (the magnitude of the asteroid) for at most 0.6 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: 22 * date and approx. time of event: 2012 Nov 23, 16:01 - 2012 Nov 23, 16:02 UT * geocentric midpoint of event [JD]: 2456255.1666 * magnitude of target star: 9.8 * magnitude drop [mag]: 6.8 * estimated maximum duration [s]: 0.6 * Moon: 79 % sunlit, 67° distance * Sun: 59° distance * rough path description: Arabia, SW Asia Additional comments ------------------- 2" double star The occultation path -------------------- * approximate projected width [km]: 25 * 1 sigma uncertainty interval [path widths]: +/- 3.12 * 1 sigma uncertainty interval [seconds]: +/- 2.7 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .057 +/- .036) * 1 sigma uncertainty ellipse (major, minor, PA): ( .057", .036", 89° ) * approx speed of asteroid's shadow [km/s]: 33.9523 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 6906-01268-1 by 428 Monachia on 2012 Nov 23 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 22 0 0 13 26 13 16 1 30 47 209 -1 13 18 38 13 33 48 12 31 33 14 21 22 23 0 0 13 58 11 16 1 33 46 210 -2 13 50 35 14 5 48 13 3 22 14 53 31 24 0 0 14 30 31 16 1 36 45 211 -3 14 22 54 14 38 9 13 35 32 15 26 1 25 0 0 15 3 10 16 1 39 44 212 -4 14 55 32 15 10 50 14 8 2 15 58 50 26 0 0 15 36 9 16 1 42 43 212 -5 15 28 29 15 43 49 14 40 51 16 31 58 27 0 0 16 9 25 16 1 45 42 213 -6 16 1 44 16 17 7 15 13 58 17 5 23 28 0 0 16 42 58 16 1 47 41 214 -7 16 35 16 16 50 41 15 47 22 17 39 5 29 0 0 17 16 47 16 1 50 40 215 -8 17 9 3 17 24 31 16 21 2 18 13 3 30 0 0 17 50 51 16 1 53 39 215 -10 17 43 6 17 58 36 16 54 58 18 47 16 31 0 0 18 25 8 16 1 55 38 216 -11 18 17 22 18 32 55 17 29 7 19 21 41 32 0 0 18 59 38 16 1 58 37 217 -12 18 51 51 19 7 26 18 3 29 19 56 20 33 0 0 19 34 19 16 2 0 36 217 -13 19 26 31 19 42 8 18 38 2 20 31 9 34 0 0 20 9 11 16 2 3 35 218 -14 20 1 22 20 17 1 19 12 47 21 6 8 35 0 0 20 44 12 16 2 5 34 219 -15 20 36 22 20 52 3 19 47 41 21 41 16 36 0 0 21 19 21 16 2 7 33 219 -16 21 11 29 21 27 12 20 22 42 22 16 32 37 0 0 21 54 36 16 2 9 32 220 -17 21 46 44 22 2 29 20 57 51 22 51 54 38 0 0 22 29 57 16 2 11 31 220 -18 22 22 4 22 37 50 21 33 6 23 27 21 39 0 0 23 5 22 16 2 14 30 221 -19 22 57 28 23 13 16 22 8 26 24 2 52 40 0 0 23 40 50 16 2 15 29 222 -20 23 32 56 23 48 45 22 43 49 24 38 25 41 0 0 24 16 20 16 2 17 28 222 -21 24 8 25 24 24 16 23 19 14 25 14 0 42 0 0 24 51 51 16 2 19 27 223 -22 24 43 55 24 59 48 23 54 40 25 49 36 43 0 0 25 27 21 16 2 21 26 223 -23 25 19 25 25 35 18 24 30 6 26 25 10 44 0 0 26 2 49 16 2 23 25 224 -24 25 54 52 26 10 47 25 5 31 27 0 42 45 0 0 26 38 15 16 2 24 24 224 -25 26 30 17 26 46 13 25 40 53 27 36 11 46 0 0 27 13 36 16 2 26 22 225 -26 27 5 38 27 21 34 26 16 11 28 11 35 47 0 0 27 48 51 16 2 27 21 225 -27 27 40 53 27 56 50 26 51 24 28 46 53 48 0 0 28 24 0 16 2 29 20 226 -28 28 16 2 28 31 59 27 26 31 29 22 4 49 0 0 28 59 1 16 2 30 19 227 -29 28 51 3 29 7 1 28 1 31 29 57 6 50 0 0 29 33 54 16 2 31 18 227 -30 29 25 55 29 41 53 28 36 22 30 32 0 51 0 0 30 8 36 16 2 32 17 228 -31 30 0 37 30 16 36 29 11 4 31 6 43 52 0 0 30 43 7 16 2 33 16 228 -32 30 35 9 30 51 7 29 45 35 31 41 14 53 0 0 31 17 26 16 2 34 15 229 -33 31 9 28 31 25 26 30 19 55 32 15 33 54 0 0 31 51 32 16 2 35 14 229 -34 31 43 34 31 59 32 30 54 1 32 49 38 55 0 0 32 25 24 16 2 36 13 230 -35 32 17 26 32 33 23 31 27 54 33 23 29 56 0 0 32 59 1 16 2 37 12 230 -36 32 51 3 33 7 0 32 1 33 33 57 3 57 0 0 33 32 21 16 2 38 11 231 -37 33 24 23 33 40 20 32 34 55 34 30 22 58 0 0 34 5 25 16 2 39 10 232 -37 33 57 27 34 13 23 33 8 2 35 3 23 59 0 0 34 38 11 16 2 39 9 232 -38 34 30 14 34 46 9 33 40 50 35 36 5 60 0 0 35 10 38 16 2 40 8 233 -39 35 2 41 35 18 35 34 13 21 36 8 29 61 0 0 35 42 45 16 2 40 7 233 -40 35 34 49 35 50 42 34 45 32 36 40 33 62 0 0 36 14 33 16 2 41 6 234 -41 36 6 37 36 22 29 35 17 24 37 12 16 63 0 0 36 45 59 16 2 41 5 234 -41 36 38 4 36 53 55 35 48 55 37 43 37 64 0 0 37 17 4 16 2 41 4 235 -42 37 9 10 37 24 59 36 20 5 38 14 37 65 0 0 37 47 47 16 2 41 3 236 -43 37 39 53 37 55 41 .. .. .. 38 45 14 66 0 0 38 18 7 16 2 42 3 236 -44 38 10 14 38 26 0 .. .. .. 39 15 28 67 0 0 38 48 3 16 2 42 2 237 -44 38 40 11 38 55 56 .. .. .. 39 45 18 68 0 0 39 17 36 16 2 42 1 238 -45 39 9 45 39 25 27 .. .. .. 40 14 44 Uncertainty in time = +/- 3 secs Prediction of 2012 Nov 16.0 Data for the target star ------------------------ * name: TYC 6906-01268-1 * constellation : Capricornus * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 20 15 35.7762 DE: -24 11 44.922 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .054, .034 ) * V mag [mag]: 9.8 * B mag [mag]: 10.3 * Diameter [mas]: 0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (428) Monachia approx. diameter [km]: 22 approx. diameter ["]: .012 distance from Earth [AU]: 2.42700 * orbital information: orbit source: Preston date of fit: 2012 Oct 07 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 1257 number of rejected observations: 42 time covered by the observations: 1904 Nov 16 - 2012 Aug 29 1 sigma uncertainty ellipse (major, minor, PA): 0.018, 0.012, 75° remarks: * orbital elements for (428) Monachia : Mean anomaly = 309.18306268 deg Arg. of pericenter = 15.64454698 deg Long. of node = 17.68023230 deg Inclination = 6.19840270 deg Eccentricity = 0.17832368 Semimajor axis = 2.30773578 AU Perihelion dist = 1.89621185 AU Mag: H = 11.88, G = 0.15 Epoch of elements : MJD 56254.66700000 TDT (2012 Nov 23.667) ------ occelmnt file for Occult BEGIN ----------------------------------- 2012 Nov 23 428 Monachia 15h 59.9m UT 9.8 20 15 35.776-24 11 44.92TYC 6906-01268-1 10.3 16.6 22 0.6 2.427 4.842 20.82 0.8954 -24.201 -63.33 -20.51 15.9984 -0.13451 0.42814 18.28254 5.74404 0.00465 0.00084 2000 307.87097620121119.00000 15.644547 17.680232 6.1984030.17832368 2.3077358 1.896211811.9 5.00.15 RATE 2.8114150 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.057 0.036 89 4.12 0.039 0 0 2-2 056247.0020121123_1268-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2012 Oct 07, 20:21 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org