IOTA/IOTA-ES occultation update for (404) Arsinoe / TYC 6325-00439-1 event on 2008 Mar 24, 22:58 UT Visible from SW Asia Summary ------- On 2008 Mar 24 UT, the 98 km diameter asteroid (404) Arsinoe will occult a 11.8 mag star in the constellation Sagittarius for observers along a path across SW Asia. In the case of an occultation, the combined light of the asteroid and the star will drop by 2.2 mag to 13.8 mag (the magnitude of the asteroid) for at most 3.3 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: 93 * date and approx. time of event: 2008 Mar 24, 22:56 - 2008 Mar 24, 22:57 UT * magnitude of target star: 11.8 * magnitude drop [mag]: 2.2 * estimated maximum duration [s]: 3.3 * Moon: 90 % sunlit, 76° distance * Sun: 68° distance * rough path description: SW Asia The occultation path -------------------- * approximate projected width [km]: 157 * 1 sigma uncertainty interval [path widths]: +/- 0.48 * 1 sigma uncertainty interval [seconds]: +/- 2.4 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .043 +/- .026) * 1 sigma uncertainty ellipse (major, minor, PA): ( .043", .026", 91° ) * approx speed of asteroid's shadow [km/s]: 29.3693 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 6325-00439-1 by 404 Arsinoe on 2008 Mar 24 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 66 0 0 45 54 21 22 56 17 1 121 -26 45 5 36 46 44 8 .. .. .. .. .. .. 67 0 0 45 29 35 22 56 17 1 122 -26 44 40 58 46 19 12 .. .. .. 47 7 53 68 0 0 45 4 55 22 56 18 2 123 -25 44 16 27 45 54 24 .. .. .. 46 42 54 69 0 0 44 40 24 22 56 18 3 123 -25 43 52 5 45 29 43 .. .. .. 46 18 4 70 0 0 44 16 1 22 56 18 4 124 -24 43 27 51 45 5 11 42 42 29 45 53 22 71 0 0 43 51 49 22 56 18 5 125 -24 43 3 48 44 40 48 42 18 33 45 28 50 72 0 0 43 27 46 22 56 19 5 125 -24 42 39 54 44 16 36 41 54 48 45 4 27 73 0 0 43 3 55 22 56 19 6 126 -23 42 16 12 43 52 35 41 31 15 44 40 16 74 0 0 42 40 16 22 56 20 7 127 -23 41 52 42 43 28 46 41 7 53 44 16 17 75 0 0 42 16 49 22 56 21 8 127 -22 41 29 25 43 5 10 40 44 44 43 52 31 76 0 0 41 53 36 22 56 21 9 128 -22 41 6 21 42 41 47 40 21 49 43 28 58 77 0 0 41 30 38 22 56 22 10 129 -21 40 43 32 42 18 38 39 59 8 43 5 39 78 0 0 41 7 54 22 56 23 10 130 -20 40 20 58 41 55 45 39 36 42 42 42 36 79 0 0 40 45 26 22 56 24 11 130 -20 39 58 39 41 33 7 39 14 32 42 19 48 80 0 0 40 23 15 22 56 25 12 131 -19 39 36 37 41 10 46 38 52 38 41 57 17 81 0 0 40 1 20 22 56 26 13 132 -19 39 14 52 40 48 42 38 31 1 41 35 3 82 0 0 39 39 44 22 56 27 14 132 -18 38 53 24 40 26 55 38 9 42 41 13 7 83 0 0 39 18 26 22 56 28 14 133 -17 38 32 15 40 5 28 37 48 42 40 51 29 84 0 0 38 57 27 22 56 30 15 134 -17 38 11 25 39 44 19 37 28 0 40 30 11 85 0 0 38 36 47 22 56 31 16 134 -16 37 50 55 39 23 31 37 7 37 40 9 13 86 0 0 38 16 28 22 56 33 17 135 -15 37 30 45 39 3 2 36 47 35 39 48 35 87 0 0 37 56 30 22 56 34 18 136 -15 37 10 55 38 42 55 36 27 54 39 28 18 88 0 0 37 36 53 22 56 36 18 137 -14 36 51 27 38 23 9 36 8 34 39 8 23 89 0 0 37 17 39 22 56 38 19 137 -13 36 32 21 38 3 46 35 49 35 38 48 51 90 0 0 36 58 47 22 56 39 20 138 -13 36 13 37 37 44 45 35 30 59 38 29 41 91 0 0 36 40 18 22 56 41 21 139 -12 35 55 17 37 26 7 35 12 46 38 10 55 92 0 0 36 22 12 22 56 43 22 140 -11 35 37 19 37 7 53 34 54 56 37 52 32 93 0 0 36 4 31 22 56 45 22 140 -10 35 19 46 36 50 4 34 37 30 37 34 34 94 0 0 35 47 14 22 56 47 23 141 -10 35 2 37 36 32 39 34 20 28 37 17 1 95 0 0 35 30 23 22 56 49 24 142 -9 34 45 53 36 15 39 34 3 50 36 59 53 96 0 0 35 13 56 22 56 51 24 143 -8 34 29 34 35 59 5 33 47 38 36 43 11 97 0 0 34 57 56 22 56 53 25 144 -7 34 13 40 35 42 56 33 31 51 36 26 55 98 0 0 34 42 21 22 56 56 26 144 -7 33 58 13 35 27 15 33 16 31 36 11 5 99 0 0 34 27 13 22 56 58 27 145 -6 33 43 12 35 12 0 33 1 36 35 55 43 100 0 0 34 12 33 22 57 0 27 146 -5 33 28 38 34 57 12 32 47 8 35 40 48 101 0 0 33 58 19 22 57 3 28 147 -4 33 14 31 34 42 52 32 33 7 35 26 21 102 0 0 33 44 33 22 57 5 29 148 -3 33 0 52 34 28 59 32 19 33 35 12 22 103 0 0 33 31 16 22 57 8 29 149 -3 32 47 40 34 15 35 32 6 27 34 58 51 104 0 0 33 18 26 22 57 11 30 150 -2 32 34 56 34 2 39 31 53 49 34 45 49 105 0 0 33 6 5 22 57 13 30 150 -1 32 22 41 33 50 12 31 41 39 34 33 17 106 0 0 32 54 13 22 57 16 31 151 0 32 10 55 33 38 15 31 29 58 34 21 13 Uncertainty in time = +/- 3 secs [Prediction of 2008 Mar 12.0] Data for the target star ------------------------ * name: TYC 6325-00439-1 * constellation : Sagittarius * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 19 55 54.2247 DE: -20 48 51.590 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .038, .024 ) * V mag [mag]: 11.8 * B mag [mag]: 12.3 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (404) Arsinoe approx. diameter [km]: 98 approx. diameter ["]: .055 distance from Earth [AU]: 2.44400 * orbital information: orbit source: Preston date of fit: 2008 Mar 12 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 858 number of rejected observations: 49 time covered by the observations: 1909 Nov 06 - 2007 Jun 07 1 sigma uncertainty ellipse (major, minor, PA): 0.021, 0.010, 96° remarks: * orbital elements for (404) Arsinoe : Mean anomaly = 40.96990670 deg Arg. of pericenter = 121.19186662 deg Long. of node = 92.67425596 deg Inclination = 14.11587076 deg Eccentricity = 0.19870188 Semimajor axis = 2.59510218 AU Perihelion dist = 2.07945048 AU Mag: H = 9.10, G = 0.15 Epoch of elements : MJD 54549.95700000 TDT (2008 Mar 24.957) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 Mar 24 404 Arsinoe 22h 58.5m UT 11.8 19 55 54.225-20 48 51.59TYC 6325-00439-1 12.3 13.8 98 3.3 2.444 4.253 1.18 131.5556 -20.814 -163.12 1.86 22.9757 -0.01546 0.78010 16.57358 0.32823 -0.00500 -0.00098 2000 38.6224322008 315.00000121.191867 92.674256 14.1158710.19870188 2.5951022 2.0794505 9.0 5.00.15 RATE 2.3576130 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.043 0.026 91 1.48 0.026 0 54537.5020080324_0439-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Mar 12, 23:47 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org