IOTA/IOTA-ES occultation update for (1242) Zambesia / TYC 7332-02287-1 event on 2009 Apr 06, 01:43 UT Visible from Summary ------- On 2009 Apr 06 UT, the 48 km diameter asteroid (1242) Zambesia will occult a 9.7 mag star in the constellation Lupus for observers along a path across . In the case of an occultation, the combined light of the asteroid and the star will drop by 5.7 mag to 15.4 mag (the magnitude of the asteroid) for at most 6.3 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: 49 * date and approx. time of event: 2009 Apr 06, 01:38 - 2009 Apr 06, 01:48 UT * magnitude of target star: 9.7 * magnitude drop [mag]: 5.7 * estimated maximum duration [s]: 6.3 * Moon: 86 % sunlit, 90° distance * Sun: 133° distance * rough path description: The occultation path -------------------- * approximate projected width [km]: 145 * 1 sigma uncertainty interval [path widths]: +/- 1.33 * 1 sigma uncertainty interval [seconds]: +/- 8.3 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .043 +/- .031) * 1 sigma uncertainty ellipse (major, minor, PA): ( .044", .031", 101° ) * approx speed of asteroid's shadow [km/s]: 7.5499 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 7332-02287-1 by 1242 Zambesia on 2009 Apr 6 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 ' " Longitude Longitude Longitude Longitude - 0 15 7 56 0 0 1 38 59 1 164 -25 - 1 32 16 0 58 59 ... .. .. ... .. .. 0 9 2 55 0 0 1 39 0 2 164 -25 - 1 5 10 1 20 27 - 4 39 21 ... .. .. 0 26 18 54 0 0 1 39 1 3 164 -26 - 0 45 25 1 35 26 - 4 11 33 ... .. .. 0 37 20 53 0 0 1 39 4 4 165 -27 - 0 32 17 1 44 32 - 3 51 44 ... .. .. 0 42 39 52 0 0 1 39 7 5 165 -28 - 0 25 12 1 48 13 - 3 39 5 ... .. .. 0 42 40 51 0 0 1 39 11 6 165 -29 - 0 23 42 1 46 52 - 3 32 59 ... .. .. 0 37 45 50 0 0 1 39 15 7 165 -30 - 0 27 24 1 40 47 - 3 32 56 4 19 43 0 28 7 49 0 0 1 39 21 8 164 -31 - 0 36 1 1 30 13 - 3 38 34 4 6 51 0 14 1 48 0 0 1 39 27 8 164 -32 - 0 49 20 1 15 21 - 3 49 35 3 50 7 - 0 4 26 47 0 0 1 39 34 9 164 -33 - 1 7 12 0 56 21 - 4 5 48 3 29 40 - 0 27 7 46 0 0 1 39 42 10 164 -34 - 1 29 30 0 33 16 - 4 27 6 3 5 33 - 0 53 59 45 0 0 1 39 51 11 163 -35 - 1 56 10 0 6 12 - 4 53 25 2 37 51 - 1 25 1 44 0 0 1 40 0 12 163 -36 - 2 27 13 - 0 24 52 - 5 24 46 2 6 33 - 2 0 16 43 0 0 1 40 10 13 162 -37 - 3 2 42 - 0 59 58 - 6 1 14 1 31 39 - 2 39 50 42 0 0 1 40 22 14 162 -38 - 3 42 42 - 1 39 10 - 6 43 1 0 53 6 - 3 23 51 41 0 0 1 40 34 14 161 -39 - 4 27 26 - 2 22 36 - 7 30 24 0 10 48 - 4 12 33 40 0 0 1 40 47 15 160 -40 - 5 17 7 - 3 10 28 - 8 23 46 - 0 35 22 - 5 6 13 39 0 0 1 41 1 16 159 -41 - 6 12 6 - 4 3 0 - 9 23 42 - 1 25 38 - 6 5 17 38 0 0 1 41 17 17 159 -42 - 7 12 54 - 5 0 35 - 10 31 2 - 2 20 12 - 7 10 16 37 0 0 1 41 33 17 158 -44 - 8 20 9 - 6 3 40 - 11 46 55 - 3 19 24 - 8 21 56 36 0 0 1 41 51 18 157 -45 - 9 34 45 - 7 12 52 - 13 13 5 - 4 23 40 - 9 41 18 35 0 0 1 42 11 18 155 -46 - 10 57 59 - 8 29 3 - 14 52 17 - 5 33 33 - 11 9 52 34 0 0 1 42 33 19 154 -48 - 12 31 44 - 9 53 24 - 16 49 10 - 6 49 47 - 12 49 48 33 0 0 1 42 57 19 153 -49 - 14 19 0 - 11 27 37 - 19 13 2 - 8 13 21 - 14 44 41 32 0 0 1 43 23 19 151 -50 - 16 24 52 - 13 14 19 - 22 28 57 - 9 45 40 - 17 0 53 31 0 0 1 43 54 19 149 -52 - 18 59 40 - 15 17 51 ... .. .. - 11 28 45 Latitude Latitude Latitude Latitude - 19 0 0 30 16 34 1 44 20 19 148 -53 30 59 53 29 34 52 33 4 51 27 50 38 - 20 0 0 29 57 41 1 44 33 19 147 -53 30 40 26 29 16 30 32 43 26 27 33 24 - 21 0 0 29 40 45 1 44 45 18 146 -54 30 23 0 29 0 1 32 24 18 27 17 54 - 22 0 0 29 25 42 1 44 57 18 145 -54 30 7 31 28 45 21 32 7 23 27 4 6 - 23 0 0 29 12 31 1 45 9 18 145 -54 29 53 58 28 32 29 31 52 37 26 51 58 - 24 0 0 29 1 9 1 45 21 18 144 -55 29 42 18 28 21 24 31 39 57 26 41 29 - 25 0 0 28 51 35 1 45 32 17 143 -55 29 32 29 28 12 3 31 29 20 26 32 37 - 26 0 0 28 43 48 1 45 43 17 143 -55 29 24 31 28 4 26 31 20 45 26 25 23 - 27 0 0 28 37 47 1 45 54 16 142 -55 29 18 22 27 58 32 31 14 9 26 19 45 - 28 0 0 28 33 31 1 46 5 16 141 -55 29 14 2 27 54 21 31 9 33 26 15 44 - 29 0 0 28 31 1 1 46 15 15 141 -55 29 11 30 27 51 52 31 6 55 26 13 19 - 30 0 0 28 30 16 1 46 25 15 140 -55 29 10 46 27 51 6 31 6 16 26 12 30 - 31 0 0 28 31 17 1 46 35 14 139 -55 29 11 52 27 52 3 31 7 35 26 13 18 - 32 0 0 28 34 4 1 46 44 14 139 -55 29 14 46 27 54 43 31 10 55 26 15 43 - 33 0 0 28 38 38 1 46 53 13 138 -54 29 19 31 27 59 8 31 16 15 26 19 45 - 34 0 0 28 45 1 1 47 1 13 138 -54 29 26 8 28 5 18 31 23 39 26 25 26 - 35 0 0 28 53 14 1 47 9 12 137 -54 29 34 39 28 13 15 31 33 7 26 32 47 - 36 0 0 29 3 19 1 47 17 11 136 -53 29 45 5 28 23 0 31 44 45 26 41 50 - 37 0 0 29 15 18 1 47 24 10 136 -53 29 57 29 28 34 36 31 58 34 26 52 35 - 38 0 0 29 29 13 1 47 31 10 135 -52 30 11 55 28 48 5 32 14 39 27 5 4 - 39 0 0 29 45 9 1 47 37 9 135 -52 30 28 25 29 3 31 32 33 5 27 19 21 - 40 0 0 30 3 9 1 47 43 8 134 -51 30 47 4 29 20 55 32 54 0 27 35 28 - 41 0 0 30 23 17 1 47 49 7 134 -51 31 7 58 29 40 23 33 17 29 27 53 27 - 42 0 0 30 45 38 1 47 54 6 133 -50 31 31 11 30 1 58 33 43 43 28 13 21 - 43 0 0 31 10 19 1 47 58 5 133 -49 31 56 51 30 25 46 34 12 52 .. .. .. - 44 0 0 31 37 26 1 48 1 5 132 -48 32 25 6 30 51 53 34 45 10 .. .. .. - 45 0 0 32 7 7 1 48 4 4 132 -48 32 56 6 31 20 27 35 20 55 .. .. .. - 46 0 0 32 39 33 1 48 7 3 131 -47 33 30 2 31 51 35 36 0 27 .. .. .. - 47 0 0 33 14 55 1 48 8 2 131 -46 34 7 9 32 25 27 .. .. .. .. .. .. - 48 0 0 33 53 29 1 48 9 1 130 -45 .. .. .. 33 2 17 .. .. .. .. .. .. Uncertainty in time = +/- 11 secs [Prediction of 2008 Mar 20.0] Data for the target star ------------------------ * name: TYC 7332-02287-1 * constellation : Lupus * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 15 51 42.2128 DE: -31 57 50.175 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .020, .020 ) * V mag [mag]: 9.7 * B mag [mag]: 9.9 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (1242) Zambesia approx. diameter [km]: 48 approx. diameter ["]: .027 distance from Earth [AU]: 2.49000 * orbital information: orbit source: Preston date of fit: 2008 Mar 19 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 733 number of rejected observations: 79 time covered by the observations: 1936 Apr 17 - 2008 Feb 13 1 sigma uncertainty ellipse (major, minor, PA): 0.039, 0.023, 104° remarks: * orbital elements for (1242) Zambesia : Mean anomaly = 190.06744707 deg Arg. of pericenter = 52.96406525 deg Long. of node = 350.06565567 deg Inclination = 10.17969680 deg Eccentricity = 0.19130991 Semimajor axis = 2.73388558 AU Perihelion dist = 2.21086617 AU Mag: H = 10.25, G = 0.15 Epoch of elements : MJD 54927.07200000 TDT (2009 Apr 06.072) ------ occelmnt file for Occult BEGIN ----------------------------------- 2009 Apr 6 1242 Zambesia 1h 43.5m UT 9.7 15 51 42.213-31 57 50.18TYC 7332-02287-1 9.9 15.4 48 6.3 2.490 -1.030 -7.41 17.5551 -31.961 154.75 6.45 1.7256 -0.46505 0.82104 -3.70761 -2.10069 -0.00392 0.00169 2000 188.5254772009 330.00000 52.964065350.065656 10.1796970.19130991 2.7338856 2.210866210.1 5.00.15 RATE 2.1803870 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.044 0.031 101 2.33 0.035 0 54545.5020090406_2287-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Mar 20, 06:51 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org