IOTA/IOTA-ES occultation update for (418) Alemannia / HIP 116344 event on 2009 May 04, 19:16 UT Visible from Summary ------- On 2009 May 04 UT, the 34 km diameter asteroid (418) Alemannia will occult a 8.7 mag star in the constellation Pisces for observers along a path across . In the case of an occultation, the combined light of the asteroid and the star will drop by 6.2 mag to 14.9 mag (the magnitude of the asteroid) for at most 0.9 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: . The event at a glimpse ---------------------- * Rank: 47 * date and approx. time of event: 2009 May 04, 19:13 - 2009 May 04, 19:14 UT * magnitude of target star: 8.7 * magnitude drop [mag]: 6.2 * estimated maximum duration [s]: 0.9 * Moon: 80 % sunlit, 175° distance * Sun: 49° distance * rough path description: The occultation path -------------------- * approximate projected width [km]: 34 * 1 sigma uncertainty interval [path widths]: +/- 1.38 * 1 sigma uncertainty interval [seconds]: +/- 1.5 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .028 +/- .021) * 1 sigma uncertainty ellipse (major, minor, PA): ( .028", .021", 83° ) * approx speed of asteroid's shadow [km/s]: 39.4485 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of HIP 116344 by 418 Alemannia on 2009 May 4 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 115 0 0 -30 52 42 19 13 39 0 86 -47 -31 1 58 -30 43 26 -31 27 32 -30 17 53 116 0 0 -30 48 48 19 13 39 1 85 -46 -30 58 4 -30 39 32 -31 23 40 -30 13 58 117 0 0 -30 44 30 19 13 39 2 85 -45 -30 53 47 -30 35 14 -31 19 23 -30 9 39 118 0 0 -30 39 48 19 13 39 3 84 -45 -30 49 5 -30 30 32 -31 14 43 -30 4 56 119 0 0 -30 34 43 19 13 40 4 84 -44 -30 44 0 -30 25 26 -31 9 39 -29 59 49 120 0 0 -30 29 14 19 13 40 5 83 -43 -30 38 31 -30 19 56 -31 4 11 -29 54 17 121 0 0 -30 23 20 19 13 40 6 83 -42 -30 32 38 -30 14 2 -30 58 20 -29 48 22 122 0 0 -30 17 3 19 13 40 6 82 -41 -30 26 22 -30 7 44 -30 52 4 -29 42 3 123 0 0 -30 10 22 19 13 41 7 82 -40 -30 19 41 -30 1 2 -30 45 25 -29 35 20 124 0 0 -30 3 16 19 13 41 8 81 -40 -30 12 36 -29 53 56 -30 38 22 -29 28 12 125 0 0 -29 55 47 19 13 41 9 81 -39 -30 5 7 -29 46 26 -30 30 55 -29 20 41 126 0 0 -29 47 53 19 13 42 10 80 -38 -29 57 14 -29 38 32 -30 23 3 -29 12 45 127 0 0 -29 39 36 19 13 42 11 80 -37 -29 48 57 -29 30 14 -30 14 48 -29 4 25 128 0 0 -29 30 54 19 13 43 12 79 -36 -29 40 16 -29 21 31 -30 6 9 -28 55 40 129 0 0 -29 21 48 19 13 43 13 79 -35 -29 31 11 -29 12 25 -29 57 6 -28 46 32 130 0 0 -29 12 18 19 13 44 14 78 -34 -29 21 41 -29 2 54 -29 47 38 -28 36 59 131 0 0 -29 2 23 19 13 44 14 78 -33 -29 11 48 -28 52 59 -29 37 47 -28 27 1 132 0 0 -28 52 4 19 13 45 15 77 -33 -29 1 30 -28 42 39 -29 27 31 -28 16 39 133 0 0 -28 41 21 19 13 46 16 77 -32 -28 50 47 -28 31 55 -29 16 51 -28 5 53 134 0 0 -28 30 14 19 13 46 17 76 -31 -28 39 41 -28 20 47 -29 5 47 -27 54 43 135 0 0 -28 18 42 19 13 47 18 76 -30 -28 28 10 -28 9 14 -28 54 18 -27 43 8 136 0 0 -28 6 46 19 13 48 19 75 -29 -28 16 15 -27 57 17 -28 42 25 -27 31 8 137 0 0 -27 54 25 19 13 49 20 75 -28 -28 3 55 -27 44 56 -28 30 8 -27 18 44 138 0 0 -27 41 41 19 13 50 21 74 -27 -27 51 11 -27 32 10 -28 17 27 -27 5 56 139 0 0 -27 28 31 19 13 51 22 74 -26 -27 38 3 -27 19 0 -28 4 21 -26 52 43 140 0 0 -27 14 58 19 13 52 23 74 -25 -27 24 30 -27 5 25 -27 50 51 -26 39 6 141 0 0 -27 1 0 19 13 53 24 73 -24 -27 10 33 -26 51 26 -27 36 57 -26 25 4 142 0 0 -26 46 37 19 13 54 24 73 -24 -26 56 12 -26 37 3 -27 22 39 -26 10 38 143 0 0 -26 31 51 19 13 55 25 72 -23 -26 41 26 -26 22 15 -27 7 56 -25 55 48 144 0 0 -26 16 40 19 13 56 26 72 -22 -26 26 16 -26 7 3 -26 52 49 -25 40 33 145 0 0 -26 1 5 19 13 57 27 71 -21 -26 10 42 -25 51 27 -26 37 18 -25 24 54 146 0 0 -25 45 5 19 13 58 28 71 -20 -25 54 44 -25 35 27 -26 21 22 -25 8 50 147 0 0 -25 28 42 19 14 0 29 70 -19 -25 38 22 -25 19 2 -26 5 3 -24 52 22 148 0 0 -25 11 54 19 14 1 30 70 -18 -25 21 35 -25 2 13 -25 48 19 -24 35 31 149 0 0 -24 54 42 19 14 2 31 69 -17 -25 4 25 -24 45 0 -25 31 12 -24 18 15 150 0 0 -24 37 7 19 14 4 32 69 -16 -24 46 50 -24 27 24 -25 13 41 -24 0 35 151 0 0 -24 19 7 19 14 5 33 68 -15 -24 28 52 -24 9 23 -24 55 45 -23 42 31 152 0 0 -24 0 44 19 14 7 34 68 -14 -24 10 30 -23 50 59 -24 37 27 -23 24 4 153 0 0 -23 41 58 19 14 8 35 68 -13 -23 51 44 -23 32 11 -24 18 44 -23 5 13 154 0 0 -23 22 47 19 14 10 36 67 -12 -23 32 35 -23 13 0 -23 59 38 -22 45 58 155 0 0 -23 3 14 19 14 12 37 67 -11 -23 13 3 -22 53 25 -23 40 9 -22 26 21 156 0 0 -22 43 17 19 14 13 38 66 -10 -22 53 7 -22 33 27 -23 20 17 -22 6 20 157 0 0 -22 22 58 19 14 15 39 66 -9 -22 32 49 -22 13 6 -23 0 1 -21 45 56 158 0 0 -22 2 15 19 14 17 40 65 -8 -22 12 8 -21 52 23 -22 39 23 -21 25 9 159 0 0 -21 41 10 19 14 19 41 65 -7 -21 51 4 -21 31 17 -22 18 23 -21 4 0 160 0 0 -21 19 43 19 14 21 42 64 -6 -21 29 37 -21 9 48 -21 57 0 -20 42 28 161 0 0 -20 57 53 19 14 23 43 64 -5 -21 7 49 -20 47 58 -21 35 15 -20 20 34 162 0 0 -20 35 42 19 14 24 44 64 -4 -20 45 39 -20 25 45 -21 13 7 -19 58 19 163 0 0 -20 13 9 19 14 26 45 63 -3 -20 23 7 -20 3 11 -20 50 39 -19 35 42 164 0 0 -19 50 15 19 14 29 46 63 -2 -20 0 14 -19 40 16 -20 27 49 -19 12 43 165 0 0 -19 27 0 19 14 31 47 62 -1 -19 37 0 -19 17 0 -20 4 38 -18 49 24 166 0 0 -19 3 24 19 14 33 48 62 0 -19 13 26 -18 53 23 -19 41 6 -18 25 44 Uncertainty in time = +/- 1 secs [Prediction of 2008 Nov 16.0] Data for the target star ------------------------ * name: HIP 116344 * constellation : Pisces * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 23 34 28.4953 DE: +03 16 41.504 * position source: mpos:HIP2 pm:HIP2 plx:HIP2 * standard error: RA,DE ["]: ( .024, .019 ) * V mag [mag]: 8.7 * B mag [mag]: 9.2 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (418) Alemannia approx. diameter [km]: 34 approx. diameter ["]: .016 distance from Earth [AU]: 2.87200 * orbital information: orbit source: Preston date of fit: 2008 Nov 16 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 704 number of rejected observations: 90 time covered by the observations: 1905 Dec 17 - 2008 Jun 03 1 sigma uncertainty ellipse (major, minor, PA): 0.016, 0.009, 69° remarks: * orbital elements for (418) Alemannia : Mean anomaly = 329.67130966 deg Arg. of pericenter = 125.49305288 deg Long. of node = 249.03956574 deg Inclination = 6.81855359 deg Eccentricity = 0.11847632 Semimajor axis = 2.59345492 AU Perihelion dist = 2.28619192 AU Mag: H = 9.72, G = 0.15 Epoch of elements : MJD 54955.80300000 TDT (2009 May 04.803) ------ occelmnt file for Occult BEGIN ----------------------------------- 2009 May 4 418 Alemannia 19h 16.3m UT 8.7 23 34 28.495 3 16 41.50HIP 116344 9.2 14.9 34 0.9 2.872 4.104 29.53 -158.2717 3.270 -109.90 16.18 19.2723 0.03951 -0.08029 20.07025 9.64114 -0.00391 -0.00131 2000 328.3018842009 429.00000125.493053249.039566 6.8185540.11847632 2.5934549 2.2861919 9.8 5.00.15 RATE 2.3598590 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.028 0.021 83 2.38 0.022 0 54786.5020090504_116344 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Nov 16, 16:48 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org