IOTA/IOTA-ES occultation update for (28958) 2001 CQ42 / HIP 664 event on 2008 May 13, 09:35 UT Visible from Bolivia, Peru Summary ------- On 2008 May 13 UT, the 13 km diameter asteroid (28958) 2001 CQ42 will occult a 6.2 mag star in the constellation Pisces for observers along a path across Bolivia, Peru. In the case of an occultation, the combined light of the asteroid and the star will drop by 13.9 mag to 20.1 mag (the magnitude of the asteroid) for at most 0.4 seconds. This update is based on historical astrometry from the MPC files (via AstDys), and the following catalogs for the star position: . The event at a glimpse ---------------------- * Rank: 2 * date and approx. time of event: 2008 May 13, 09:32 - 2008 May 13, 09:33 UT * midpoint of event [JD]: 2454599.89969167 * magnitude of target star: 6.2 * magnitude drop [mag]: 13.9 * estimated maximum duration [s]: 0.4 * Moon: 63 % sunlit, 156° distance * Sun: 52° distance * rough path description: Bolivia, Peru The occultation path -------------------- * approximate projected width [km]: 13 * 1 sigma uncertainty interval [path widths]: +/- 25.94 * 1 sigma uncertainty interval [seconds]: +/- 28.6 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .210 +/- .098) * 1 sigma uncertainty ellipse (major, minor, PA): ( .218", .078", 73° ) * approx speed of asteroid's shadow [km/s]: 31.6687 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of HIP 664 by 28958 2001 CQ42 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 -103 0 0 -17 34 46 9 32 12 0 92 -51 -17 38 18 -17 31 15 -20 41 18 -14 28 4 -102 0 0 -17 37 6 9 32 12 1 92 -50 -17 40 37 -17 33 34 -20 43 35 -14 30 26 -101 0 0 -17 39 6 9 32 12 2 92 -49 -17 42 38 -17 35 34 -20 45 33 -14 32 28 -100 0 0 -17 40 47 9 32 12 3 92 -48 -17 44 19 -17 37 16 -20 47 12 -14 34 11 - 99 0 0 -17 42 9 9 32 12 4 91 -47 -17 45 41 -17 38 38 -20 48 33 -14 35 35 - 98 0 0 -17 43 12 9 32 13 5 91 -46 -17 46 44 -17 39 41 -20 49 35 -14 36 39 - 97 0 0 -17 43 56 9 32 13 6 91 -45 -17 47 28 -17 40 25 -20 50 18 -14 37 23 - 96 0 0 -17 44 21 9 32 13 7 90 -45 -17 47 53 -17 40 50 -20 50 42 -14 37 49 - 95 0 0 -17 44 27 9 32 14 8 90 -44 -17 47 58 -17 40 55 -20 50 48 -14 37 54 - 94 0 0 -17 44 13 9 32 14 9 90 -43 -17 47 45 -17 40 42 -20 50 35 -14 37 41 - 93 0 0 -17 43 41 9 32 15 10 89 -42 -17 47 12 -17 40 9 -20 50 3 -14 37 8 - 92 0 0 -17 42 49 9 32 15 11 89 -41 -17 46 20 -17 39 18 -20 49 12 -14 36 15 - 91 0 0 -17 41 38 9 32 16 12 89 -40 -17 45 10 -17 38 7 -20 48 2 -14 35 2 - 90 0 0 -17 40 8 9 32 17 13 89 -39 -17 43 39 -17 36 36 -20 46 34 -14 33 31 - 89 0 0 -17 38 19 9 32 17 14 88 -38 -17 41 50 -17 34 47 -20 44 46 -14 31 39 - 88 0 0 -17 36 10 9 32 18 14 88 -37 -17 39 42 -17 32 38 -20 42 40 -14 29 28 - 87 0 0 -17 33 42 9 32 19 15 88 -36 -17 37 14 -17 30 11 -20 40 15 -14 26 58 - 86 0 0 -17 30 56 9 32 20 16 87 -35 -17 34 27 -17 27 24 -20 37 31 -14 24 8 - 85 0 0 -17 27 50 9 32 21 17 87 -34 -17 31 21 -17 24 18 -20 34 29 -14 20 59 - 84 0 0 -17 24 24 9 32 22 18 87 -33 -17 27 56 -17 20 52 -20 31 7 -14 17 30 - 83 0 0 -17 20 40 9 32 23 19 86 -32 -17 24 12 -17 17 8 -20 27 27 -14 13 41 - 82 0 0 -17 16 37 9 32 24 20 86 -31 -17 20 9 -17 13 5 -20 23 28 -14 9 33 - 81 0 0 -17 12 14 9 32 25 21 86 -30 -17 15 46 -17 8 42 -20 19 10 -14 5 6 - 80 0 0 -17 7 32 9 32 27 22 86 -29 -17 11 5 -17 4 0 -20 14 34 -14 0 19 - 79 0 0 -17 2 32 9 32 28 23 85 -28 -17 6 4 -16 58 59 -20 9 38 -13 55 13 - 78 0 0 -16 57 12 9 32 29 24 85 -27 -17 0 44 -16 53 40 -20 4 24 -13 49 48 - 77 0 0 -16 51 33 9 32 31 25 85 -26 -16 55 6 -16 48 1 -19 58 51 -13 44 3 - 76 0 0 -16 45 36 9 32 32 26 84 -26 -16 49 8 -16 42 3 -19 53 0 -13 37 59 - 75 0 0 -16 39 19 9 32 34 27 84 -25 -16 42 52 -16 35 46 -19 46 50 -13 31 36 - 74 0 0 -16 32 44 9 32 35 28 84 -24 -16 36 16 -16 29 11 -19 40 22 -13 24 53 - 73 0 0 -16 25 49 9 32 37 29 84 -23 -16 29 22 -16 22 16 -19 33 34 -13 17 52 - 72 0 0 -16 18 36 9 32 39 30 83 -22 -16 22 9 -16 15 3 -19 26 29 -13 10 31 - 71 0 0 -16 11 4 9 32 40 31 83 -21 -16 14 38 -16 7 31 -19 19 5 -13 2 52 - 70 0 0 -16 3 14 9 32 42 32 83 -20 -16 6 48 -15 59 41 -19 11 22 -12 54 53 - 69 0 0 -15 55 5 9 32 44 33 82 -19 -15 58 39 -15 51 31 -19 3 22 -12 46 36 - 68 0 0 -15 46 37 9 32 46 34 82 -18 -15 50 11 -15 43 4 -18 55 3 -12 38 0 - 67 0 0 -15 37 51 9 32 48 35 82 -17 -15 41 25 -15 34 18 -18 46 26 -12 29 5 - 66 0 0 -15 28 47 9 32 50 36 82 -16 -15 32 21 -15 25 13 -18 37 30 -12 19 51 - 65 0 0 -15 19 24 9 32 52 37 81 -15 -15 22 59 -15 15 50 -18 28 17 -12 10 20 - 64 0 0 -15 9 44 9 32 54 38 81 -14 -15 13 18 -15 6 9 -18 18 45 -12 0 29 - 63 0 0 -14 59 45 9 32 56 39 81 -13 -15 3 19 -14 56 10 -18 8 56 -11 50 21 - 62 0 0 -14 49 28 9 32 58 40 81 -12 -14 53 3 -14 45 53 -17 58 49 -11 39 54 - 61 0 0 -14 38 53 9 33 1 41 80 -11 -14 42 28 -14 35 18 -17 48 24 -11 29 9 - 60 0 0 -14 28 0 9 33 3 42 80 -10 -14 31 36 -14 24 25 -17 37 42 -11 18 6 - 59 0 0 -14 16 50 9 33 5 43 80 -9 -14 20 25 -14 13 15 -17 26 42 -11 6 45 - 58 0 0 -14 5 22 9 33 8 44 80 -8 -14 8 58 -14 1 47 -17 15 25 -10 55 7 - 57 0 0 -13 53 37 9 33 10 45 79 -7 -13 57 13 -13 50 1 -17 3 50 -10 43 11 - 56 0 0 -13 41 34 9 33 13 46 79 -6 -13 45 11 -13 37 58 -16 51 58 -10 30 58 - 55 0 0 -13 29 15 9 33 15 47 79 -5 -13 32 51 -13 25 39 -16 39 50 -10 18 27 - 54 0 0 -13 16 38 9 33 18 48 79 -4 -13 20 15 -13 13 2 -16 27 24 -10 5 40 - 53 0 0 -13 3 45 9 33 20 49 79 -3 -13 7 22 -13 0 8 -16 14 42 - 9 52 35 - 52 0 0 -12 50 35 9 33 23 50 78 -2 -12 54 12 -12 46 58 -16 1 43 - 9 39 14 - 51 0 0 -12 37 9 9 33 26 51 78 -1 -12 40 46 -12 33 31 -15 48 28 - 9 25 36 Uncertainty in time = +/- 29 secs [Prediction of 2008 Feb 17.0] Data for the target star ------------------------ * name: HIP 664 * constellation : Pisces * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 00 08 12.1003 DE: -02 26 51.798 * position source: mpos:HIP pm:HIP plx:HIP * standard error: RA,DE ["]: ( .022, .010 ) * V mag [mag]: 6.2 * B mag [mag]: 7.5 * Apparent position with proper motion RA(deg): 2.1566104243 DE(deg): -2.4012823111 * Equation of equinoxes (radians) : 0.000040986510229 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (28958) 2001 CQ42 approx. diameter [km]: 13 approx. diameter ["]: .003 distance from Earth [AU]: 5.72900 * orbital information: orbit source: Preston date of fit: 2008 Feb 16 source of used astrometry: MPC (via Astdys) number of used observations: 132 number of rejected observations: 1 time covered by the observations: 1995 Jul 24 - 2007 Sep 11 1 sigma uncertainty ellipse (major, minor, PA): 0.217, 0.077, 73° remarks: * orbital elements for (28958) 2001 CQ42 : Mean anomaly = 288.55368589 deg Arg. of pericenter = 285.15314430 deg Long. of node = 147.84689616 deg Inclination = 8.23425840 deg Eccentricity = 0.08311499 Semimajor axis = 5.27469432 AU Perihelion dist = 4.83628817 AU Mag: H = 11.85, G = 0.15 Epoch of elements : MJD 54599.40000000 TDT (2008 May 13.400) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 May 13 28958 2001 CQ42 9h 35.6m UT 6.2 0 8 12.100- 2 26 51.80HIP 664 7.6 20.1 13 0.4 5.729 1.738 8.62 -13.3552 -2.450 35.20 18.52 9.5926 -0.00357 0.01427 16.96886 5.61809 -0.00417 -0.00202 2000 287.7889072008 5 4.00000285.153144147.846896 8.2342580.08311499 5.2746943 4.836288212.1 5.00.15 RATE 0.8135950 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.218 0.078 73 26.94 0.081 0 54513.5020080513____664 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Apr 09, 17:07 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org