IOTA/IOTA-ES occultation update for (635) Vundtia / 2UCAC 30617032 event on 2008 May 13, 03:58 UT Visible from Africa Summary ------- On 2008 May 13 UT, the 98 km diameter asteroid (635) Vundtia will occult a 12.2 mag star in the constellation Aquarius 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 2.8 mag to 14.9 mag (the magnitude of the asteroid) for at most 5.2 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: 61 * date and approx. time of event: 2008 May 13, 03:53 - 2008 May 13, 03:58 UT * midpoint of event [JD]: 2454599.66581667 * magnitude of target star: 12.2 * magnitude drop [mag]: 2.8 * estimated maximum duration [s]: 5.2 * Moon: 60 % sunlit, 169° distance * Sun: 85° distance * rough path description: Africa The occultation path -------------------- * approximate projected width [km]: 98 * 1 sigma uncertainty interval [path widths]: +/- 1.01 * 1 sigma uncertainty interval [seconds]: +/- 5.2 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .044 +/- .044) * 1 sigma uncertainty ellipse (major, minor, PA): ( .044", .044", 359° ) * approx speed of asteroid's shadow [km/s]: 18.9466 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of 2UCAC 30617032 by 635 Vundtia on 2008 May 13 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 - 55 0 0 -29 45 14 3 53 11 0 94 -78 -30 11 54 -29 18 34 -31 5 49 .. .. .. - 54 0 0 -29 48 48 3 53 11 1 94 -78 -30 15 28 -29 22 10 -31 9 21 -28 28 23 - 53 0 0 -29 51 59 3 53 11 2 93 -77 -30 18 38 -29 25 21 -31 12 30 -28 31 36 - 52 0 0 -29 54 46 3 53 11 3 93 -77 -30 21 24 -29 28 9 -31 15 14 -28 34 24 - 51 0 0 -29 57 8 3 53 12 4 92 -76 -30 23 46 -29 30 32 -31 17 35 -28 36 49 - 50 0 0 -29 59 7 3 53 12 4 92 -76 -30 25 44 -29 32 31 -31 19 33 -28 38 49 - 49 0 0 -30 0 42 3 53 12 5 91 -75 -30 27 18 -29 34 6 -31 21 6 -28 40 25 - 48 0 0 -30 1 53 3 53 13 6 91 -75 -30 28 29 -29 35 17 -31 22 16 -28 41 36 - 47 0 0 -30 2 39 3 53 14 7 90 -74 -30 29 15 -29 36 4 -31 23 2 -28 42 24 - 46 0 0 -30 3 2 3 53 14 8 90 -73 -30 29 38 -29 36 27 -31 23 24 -28 42 47 - 45 0 0 -30 3 0 3 53 15 9 89 -73 -30 29 36 -29 36 25 -31 23 22 -28 42 45 - 44 0 0 -30 2 34 3 53 16 10 89 -72 -30 29 10 -29 35 59 -31 22 57 -28 42 19 - 43 0 0 -30 1 45 3 53 17 10 88 -71 -30 28 21 -29 35 9 -31 22 8 -28 41 29 - 42 0 0 -30 0 31 3 53 18 11 88 -71 -30 27 7 -29 33 55 -31 20 55 -28 40 14 - 41 0 0 -29 58 52 3 53 19 12 87 -70 -30 25 29 -29 32 16 -31 19 17 -28 38 34 - 40 0 0 -29 56 50 3 53 20 13 87 -69 -30 23 27 -29 30 13 -31 17 16 -28 36 31 - 39 0 0 -29 54 23 3 53 21 14 86 -68 -30 21 1 -29 27 46 -31 14 51 -28 34 2 - 38 0 0 -29 51 32 3 53 22 15 86 -68 -30 18 11 -29 24 54 -31 12 2 -28 31 9 - 37 0 0 -29 48 17 3 53 24 16 85 -67 -30 14 56 -29 21 38 -31 8 49 -28 27 51 - 36 0 0 -29 44 37 3 53 25 17 85 -66 -30 11 17 -29 17 58 -31 5 12 -28 24 9 - 35 0 0 -29 40 33 3 53 27 17 84 -65 -30 7 14 -29 13 53 -31 1 11 -28 20 2 - 34 0 0 -29 36 4 3 53 28 18 84 -64 -30 2 46 -29 9 23 -30 56 45 -28 15 30 - 33 0 0 -29 31 11 3 53 30 19 83 -64 -29 57 55 -29 4 29 -30 51 56 -28 10 34 - 32 0 0 -29 25 54 3 53 32 20 83 -63 -29 52 38 -28 59 10 -30 46 42 -28 5 12 - 31 0 0 -29 20 12 3 53 33 21 82 -62 -29 46 57 -28 53 26 -30 41 4 -27 59 26 - 30 0 0 -29 14 5 3 53 35 22 82 -61 -29 40 52 -28 47 18 -30 35 1 -27 53 15 - 29 0 0 -29 7 33 3 53 37 23 81 -60 -29 34 22 -28 40 45 -30 28 34 -27 46 39 - 28 0 0 -29 0 37 3 53 39 24 81 -60 -29 27 27 -28 33 47 -30 21 43 -27 39 38 - 27 0 0 -28 53 16 3 53 42 25 80 -59 -29 20 8 -28 26 25 -30 14 27 -27 32 12 - 26 0 0 -28 45 30 3 53 44 25 80 -58 -29 12 24 -28 18 37 -30 6 47 -27 24 21 - 25 0 0 -28 37 20 3 53 46 26 79 -57 -29 4 15 -28 10 25 -29 58 42 -27 16 5 - 24 0 0 -28 28 44 3 53 48 27 79 -56 -28 55 42 -28 1 47 -29 50 12 -27 7 23 - 23 0 0 -28 19 44 3 53 51 28 78 -55 -28 46 44 -27 52 45 -29 41 18 -26 58 17 - 22 0 0 -28 10 18 3 53 53 29 78 -54 -28 37 20 -27 43 17 -29 31 59 -26 48 45 - 21 0 0 -28 0 28 3 53 56 30 77 -54 -28 27 32 -27 33 25 -29 22 16 -26 38 48 - 20 0 0 -27 50 13 3 53 59 31 77 -53 -28 17 19 -27 23 7 -29 12 7 -26 28 25 - 19 0 0 -27 39 32 3 54 2 32 76 -52 -28 6 41 -27 12 24 -29 1 34 -26 17 38 - 18 0 0 -27 28 27 3 54 5 33 76 -51 -27 55 38 -27 1 16 -28 50 36 -26 6 25 - 17 0 0 -27 16 56 3 54 7 34 75 -50 -27 44 10 -26 49 43 -28 39 13 -25 54 46 - 16 0 0 -27 5 0 3 54 11 35 75 -49 -27 32 16 -26 37 44 -28 27 24 -25 42 42 - 15 0 0 -26 52 39 3 54 14 35 74 -48 -27 19 58 -26 25 20 -28 15 11 -25 30 13 - 14 0 0 -26 39 52 3 54 17 36 74 -47 -27 7 14 -26 12 31 -28 2 33 -25 17 19 - 13 0 0 -26 26 41 3 54 20 37 73 -46 -26 54 5 -25 59 17 -27 49 30 -25 3 59 - 12 0 0 -26 13 4 3 54 24 38 73 -46 -26 40 32 -25 45 37 -27 36 2 -24 50 13 - 11 0 0 -25 59 2 3 54 27 39 72 -45 -26 26 32 -25 31 32 -27 22 9 -24 36 2 - 10 0 0 -25 44 35 3 54 31 40 72 -44 -26 12 8 -25 17 2 -27 7 51 -24 21 26 - 9 0 0 -25 29 42 3 54 34 41 71 -43 -25 57 19 -25 2 7 -26 53 8 -24 6 24 - 8 0 0 -25 14 25 3 54 38 42 71 -42 -25 42 4 -24 46 46 -26 38 0 -23 50 57 - 7 0 0 -24 58 42 3 54 42 43 70 -41 -25 26 25 -24 31 0 -26 22 26 -23 35 5 - 6 0 0 -24 42 34 3 54 46 44 70 -40 -25 10 20 -24 14 49 -26 6 28 -23 18 47 - 5 0 0 -24 26 1 3 54 50 45 69 -39 -24 53 50 -23 58 13 -25 50 5 -23 2 5 - 4 0 0 -24 9 3 3 54 54 46 69 -38 -24 36 56 -23 41 12 -25 33 17 -22 44 57 - 3 0 0 -23 51 40 3 54 58 47 68 -37 -24 19 36 -23 23 45 -25 16 4 -22 27 24 - 2 0 0 -23 33 53 3 55 2 48 68 -36 -24 1 52 -23 5 54 -24 58 27 -22 9 26 - 1 0 0 -23 15 40 3 55 6 49 67 -35 -23 43 43 -22 47 38 -24 40 25 -21 51 3 0 0 0 -22 57 3 3 55 11 50 67 -34 -23 25 9 -22 28 58 -24 21 58 -21 32 16 1 0 0 -22 38 1 3 55 15 51 66 -33 -23 6 11 -22 9 53 -24 3 7 -21 13 4 2 0 0 -22 18 35 3 55 20 52 66 -32 -22 46 48 -21 50 23 -23 43 51 -20 53 27 3 0 0 -21 58 45 3 55 24 53 65 -31 -22 27 1 -21 30 29 -23 24 11 -20 33 27 4 0 0 -21 38 30 3 55 29 54 65 -30 -22 6 50 -21 10 11 -23 4 7 -20 13 2 5 0 0 -21 17 52 3 55 34 55 64 -29 -21 46 15 -20 49 30 -22 43 39 -19 52 13 6 0 0 -20 56 50 3 55 39 56 64 -28 -21 25 17 -20 28 24 -22 22 48 -19 31 0 7 0 0 -20 35 25 3 55 44 57 63 -27 -21 3 55 -20 6 55 -22 1 33 -19 9 24 8 0 0 -20 13 36 3 55 49 58 63 -26 -20 42 10 -19 45 3 -21 39 55 -18 47 25 9 0 0 -19 51 24 3 55 54 59 62 -25 -20 20 1 -19 22 48 -21 17 53 -18 25 3 10 0 0 -19 28 49 3 55 59 60 62 -24 -19 57 30 -19 0 10 -20 55 29 -18 2 18 11 0 0 -19 5 52 3 56 5 61 61 -23 -19 34 37 -18 37 9 -20 32 42 -17 39 11 12 0 0 -18 42 33 3 56 10 62 61 -22 -19 11 21 -18 13 47 -20 9 33 -17 15 42 13 0 0 -18 18 52 3 56 16 63 60 -21 -18 47 43 -17 50 3 -19 46 3 -16 51 51 14 0 0 -17 54 50 3 56 21 64 59 -20 -18 23 44 -17 25 57 -19 22 10 -16 27 39 15 0 0 -17 30 27 3 56 27 65 59 -19 -17 59 24 -17 1 30 -18 57 57 -16 3 5 16 0 0 -17 5 43 3 56 32 66 58 -18 -17 34 43 -16 36 43 -18 33 22 -15 38 12 17 0 0 -16 40 38 3 56 38 67 57 -17 -17 9 42 -16 11 36 -18 8 28 -15 12 58 18 0 0 -16 15 14 3 56 44 68 57 -16 -16 44 21 -15 46 9 -17 43 13 -14 47 25 19 0 0 -15 49 31 3 56 50 69 56 -15 -16 18 41 -15 20 22 -17 17 39 -14 21 32 20 0 0 -15 23 29 3 56 56 70 55 -14 -15 52 41 -14 54 17 -16 51 45 -13 55 21 21 0 0 -14 57 8 3 57 2 71 54 -13 -15 26 24 -14 27 54 -16 25 33 -13 28 52 22 0 0 -14 30 30 3 57 8 72 53 -12 -14 59 48 -14 1 13 -15 59 3 -13 2 6 23 0 0 -14 3 34 3 57 14 74 52 -11 -14 32 55 -13 34 14 -15 32 16 -12 35 2 24 0 0 -13 36 22 3 57 20 75 51 -10 -14 5 46 -13 7 0 -15 5 12 -12 7 42 25 0 0 -13 8 54 3 57 27 76 50 -9 -13 38 20 -12 39 29 -14 37 51 -11 40 6 26 0 0 -12 41 10 3 57 33 77 48 -7 -13 10 39 -12 11 43 -14 10 15 -11 12 16 27 0 0 -12 13 12 3 57 39 78 47 -6 -12 42 43 -11 43 42 -13 42 23 -10 44 10 28 0 0 -11 45 0 3 57 46 79 45 -5 -12 14 32 -11 15 28 -13 14 17 -10 15 51 29 0 0 -11 16 34 3 57 52 80 42 -4 -11 46 9 -10 47 0 -12 45 58 - 9 47 19 30 0 0 -10 47 55 3 57 58 81 39 -3 -11 17 32 -10 18 20 -12 17 25 - 9 18 35 31 0 0 -10 19 5 3 58 5 82 36 -2 -10 48 44 - 9 49 27 -11 48 40 - 8 49 39 32 0 0 - 9 50 3 3 58 11 83 31 -1 -10 19 44 - 9 20 24 -11 19 44 - 8 20 33 Uncertainty in time = +/- 5 secs [Prediction of 2008 Apr 9.0] Data for the target star ------------------------ * name: 2UCAC 30617032 * constellation : Aquarius * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 21 45 47.5487 DE: -03 39 12.611 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .040, .043 ) * V mag [mag]: 12.2 * B mag [mag]: 0.0 * Apparent position with proper motion RA(deg): 326.5591966999 DE(deg): -3.6159696819 * Equation of equinoxes (radians) : 0.000041055663304 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (635) Vundtia approx. diameter [km]: 98 approx. diameter ["]: .044 distance from Earth [AU]: 3.07200 * orbital information: orbit source: Preston date of fit: 2008 Apr 08 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 722 number of rejected observations: 95 time covered by the observations: 1908 Aug 20 - 2007 Oct 09 1 sigma uncertainty ellipse (major, minor, PA): 0.019, 0.012, 80° remarks: * orbital elements for (635) Vundtia : Mean anomaly = 272.16124173 deg Arg. of pericenter = 221.58468135 deg Long. of node = 183.12226165 deg Inclination = 11.02204631 deg Eccentricity = 0.07696055 Semimajor axis = 3.14375412 AU Perihelion dist = 2.90180909 AU Mag: H = 8.98, G = 0.15 Epoch of elements : MJD 54599.16600000 TDT (2008 May 13.166) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 May 13 635 Vundtia 3h 58.8m UT 12.2 21 45 47.549- 3 39 12.612UCAC 30617032 0.0 14.9 98 5.2 3.072 1.843 13.27 35.4678 -3.657 119.40 18.47 3.9796 0.02990 -0.06213 9.63678 4.63617 -0.00538 -0.00184 2000 270.5405112008 5 4.00000221.584681183.122262 11.0220460.07696055 3.1437541 2.9018091 9.0 5.00.15 RATE 1.7681990 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.044 0.044 359 2.01 0.044 0 54565.5020080513_617032 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Apr 09, 17:06 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org