IOTA/IOTA-ES occultation update for (3560) Chenqian / HIP 24571 event on 2008 Mar 30, 22:54 UT Visible from W Africa Summary ------- On 2008 Mar 30 UT, the 30 km diameter asteroid (3560) Chenqian will occult a 9.4 mag star in the constellation Auriga for observers along a path across W Africa. In the case of an occultation, the combined light of the asteroid and the star will drop by 6.8 mag to 16.2 mag (the magnitude of the asteroid) for at most 1.1 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: 25 * date and approx. time of event: 2008 Mar 30, 22:56 - 2008 Mar 30, 22:58 UT * midpoint of event [JD]: 2454556.45490833 * magnitude of target star: 9.4 * magnitude drop [mag]: 6.8 * estimated maximum duration [s]: 1.1 * Moon: 39 % sunlit, 147° distance * Sun: 70° distance * rough path description: W Africa The occultation path -------------------- * approximate projected width [km]: 31 * 1 sigma uncertainty interval [path widths]: +/- 2.68 * 1 sigma uncertainty interval [seconds]: +/- 2.5 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .036 +/- .035) * 1 sigma uncertainty ellipse (major, minor, PA): ( .036", .035", 95° ) * approx speed of asteroid's shadow [km/s]: 27.5299 * website for maps: http://lunar-occultations.com/iota/asteroids/astrndx.htm http://www.asteroidoccultation.com Path Coordinates: Occultation of HIP 24571 by 3560 Chenqian on 2008 Mar 30 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 - 68 0 0 43 24 10 22 56 11 65 244 -1 43 15 15 43 33 6 42 27 32 44 21 7 - 67 0 0 43 9 56 22 56 14 65 246 -2 43 0 59 43 18 53 42 13 8 44 7 2 - 66 0 0 42 55 15 22 56 17 64 248 -2 42 46 17 43 4 14 41 58 18 43 52 30 - 65 0 0 42 40 8 22 56 20 63 250 -3 42 31 8 42 49 8 41 43 2 43 37 32 - 64 0 0 42 24 34 22 56 23 63 251 -4 42 15 32 42 33 35 41 27 18 43 22 8 - 63 0 0 42 8 33 22 56 26 62 253 -5 41 59 30 42 17 36 41 11 8 43 6 16 - 62 0 0 41 52 5 22 56 29 62 254 -5 41 43 0 42 1 9 40 54 30 42 49 58 - 61 0 0 41 35 10 22 56 32 61 256 -6 41 26 4 41 44 16 40 37 25 42 33 13 - 60 0 0 41 17 47 22 56 35 60 257 -7 41 8 40 41 26 55 40 19 53 42 16 1 - 59 0 0 40 59 58 22 56 38 60 259 -8 40 50 49 41 9 7 40 1 54 41 58 22 - 58 0 0 40 41 41 22 56 41 59 260 -9 40 32 30 40 50 52 39 43 27 41 40 15 - 57 0 0 40 22 56 22 56 44 58 262 -9 40 13 44 40 32 9 39 24 32 41 21 41 - 56 0 0 40 3 44 22 56 47 57 263 -10 39 54 30 40 12 59 39 5 10 41 2 39 - 55 0 0 39 44 5 22 56 50 57 264 -11 39 34 49 39 53 21 38 45 20 40 43 10 - 54 0 0 39 23 57 22 56 53 56 266 -12 39 14 40 39 33 15 38 25 2 40 23 13 - 53 0 0 39 3 22 22 56 56 55 267 -13 38 54 3 39 12 42 38 4 16 40 2 49 - 52 0 0 38 42 19 22 56 59 54 268 -14 38 32 59 38 51 40 37 43 3 39 41 56 - 51 0 0 38 20 49 22 57 2 54 269 -15 38 11 27 38 30 11 37 21 22 39 20 36 - 50 0 0 37 58 50 22 57 5 53 270 -15 37 49 27 38 8 15 36 59 13 38 58 48 - 49 0 0 37 36 24 22 57 8 52 271 -16 37 26 59 37 45 50 36 36 37 38 36 33 - 48 0 0 37 13 30 22 57 11 51 272 -17 37 4 3 37 22 58 36 13 33 38 13 50 - 47 0 0 36 50 9 22 57 14 50 273 -18 36 40 40 36 59 38 35 50 1 37 50 39 - 46 0 0 36 26 20 22 57 17 50 274 -19 36 16 50 36 35 51 35 26 2 37 27 0 - 45 0 0 36 2 4 22 57 20 49 275 -20 35 52 32 36 11 36 35 1 36 37 2 54 - 44 0 0 35 37 20 22 57 23 48 276 -21 35 27 47 35 46 54 34 36 42 36 38 21 - 43 0 0 35 12 10 22 57 26 47 277 -22 35 2 35 35 21 45 34 11 22 36 13 20 - 42 0 0 34 46 32 22 57 29 46 278 -23 34 36 56 34 56 10 33 45 35 35 47 53 - 41 0 0 34 20 28 22 57 31 45 279 -24 34 10 50 34 30 7 33 19 21 35 21 58 - 40 0 0 33 53 58 22 57 34 44 280 -25 33 44 18 34 3 38 32 52 41 34 55 38 - 39 0 0 33 27 1 22 57 37 43 281 -25 33 17 20 33 36 43 32 25 36 34 28 51 - 38 0 0 32 59 39 22 57 40 42 282 -26 32 49 57 33 9 22 31 58 4 34 1 37 - 37 0 0 32 31 51 22 57 43 42 282 -27 32 22 7 32 41 36 31 30 8 33 33 59 - 36 0 0 32 3 39 22 57 45 41 283 -28 31 53 53 32 13 24 31 1 46 33 5 55 - 35 0 0 31 35 1 22 57 48 40 284 -29 31 25 15 31 44 48 30 33 1 32 37 26 - 34 0 0 31 5 59 22 57 51 39 285 -30 30 56 12 31 15 48 30 3 51 32 8 32 - 33 0 0 30 36 34 22 57 53 38 285 -31 30 26 45 30 46 24 29 34 18 31 39 15 - 32 0 0 30 6 46 22 57 56 37 286 -32 29 56 56 30 16 37 29 4 22 31 9 34 - 31 0 0 29 36 35 22 57 58 36 287 -33 29 26 43 29 46 27 28 34 4 30 39 30 - 30 0 0 29 6 2 22 58 1 35 287 -34 28 56 9 29 15 55 28 3 24 30 9 4 - 29 0 0 28 35 7 22 58 3 34 288 -35 28 25 14 28 45 1 27 32 23 29 38 16 - 28 0 0 28 3 52 22 58 6 33 289 -36 27 53 57 28 13 47 27 1 2 29 7 7 - 27 0 0 27 32 17 22 58 8 32 289 -37 27 22 21 27 42 12 26 29 21 28 35 38 - 26 0 0 27 0 22 22 58 10 31 290 -38 26 50 26 27 10 19 25 57 21 28 3 49 - 25 0 0 26 28 9 22 58 13 30 290 -40 26 18 12 26 38 6 25 25 3 27 31 40 - 24 0 0 25 55 38 22 58 15 29 291 -41 25 45 40 26 5 36 24 52 27 26 59 14 - 23 0 0 25 22 50 22 58 17 28 291 -42 25 12 52 25 32 49 24 19 35 26 26 31 - 22 0 0 24 49 46 22 58 19 27 292 -43 24 39 47 24 59 46 23 46 28 25 53 31 - 21 0 0 24 16 27 22 58 21 26 292 -44 24 6 28 24 26 27 23 13 6 25 20 15 - 20 0 0 23 42 54 22 58 23 25 293 -45 23 32 54 23 52 55 22 39 29 24 46 45 - 19 0 0 23 9 8 22 58 25 23 293 -46 22 59 7 23 19 9 22 5 41 24 13 1 - 18 0 0 22 35 9 22 58 27 22 294 -47 22 25 8 22 45 10 21 31 40 23 39 4 - 17 0 0 22 0 59 22 58 28 21 294 -48 21 50 58 22 11 0 20 57 28 23 4 55 - 16 0 0 21 26 38 22 58 30 20 295 -49 21 16 37 21 36 40 20 23 7 22 30 36 - 15 0 0 20 52 9 22 58 32 19 295 -50 20 42 8 21 2 11 19 48 37 21 56 7 - 14 0 0 20 17 31 22 58 33 18 295 -51 20 7 30 20 27 33 19 13 59 21 21 30 - 13 0 0 19 42 46 22 58 35 17 296 -53 19 32 45 19 52 48 18 39 15 20 46 45 - 12 0 0 19 7 56 22 58 36 16 296 -54 18 57 55 19 17 57 18 4 25 20 11 53 - 11 0 0 18 33 0 22 58 37 15 297 -55 18 22 59 18 43 1 17 29 30 19 36 56 - 10 0 0 17 58 0 22 58 38 14 297 -56 17 48 0 18 8 2 16 54 32 19 1 55 - 9 0 0 17 22 58 22 58 39 12 297 -57 17 12 58 17 32 59 16 19 32 18 26 51 - 8 0 0 16 47 55 22 58 40 11 298 -58 16 37 55 16 57 55 15 44 31 17 51 44 - 7 0 0 16 12 51 22 58 41 10 298 -59 16 2 52 16 22 51 15 9 30 17 16 37 - 6 0 0 15 37 48 22 58 42 9 298 -60 15 27 49 15 47 47 14 34 31 16 41 31 - 5 0 0 15 2 46 22 58 43 8 298 -61 14 52 48 15 12 45 13 59 33 16 6 25 - 4 0 0 14 27 48 22 58 43 7 299 -63 14 17 50 14 37 46 13 24 39 15 31 23 - 3 0 0 13 52 54 22 58 44 6 299 -64 13 42 57 14 2 51 12 49 50 14 56 24 - 2 0 0 13 18 5 22 58 44 5 299 -65 13 8 9 13 28 1 12 15 6 14 21 30 - 1 0 0 12 43 22 22 58 45 3 299 -66 12 33 27 12 53 18 .. .. .. 13 46 42 0 0 0 12 8 47 22 58 45 2 300 -67 11 58 53 12 18 42 .. .. .. 13 12 1 1 0 0 11 34 20 22 58 45 1 300 -68 11 24 27 11 44 14 .. .. .. 12 37 28 2 0 0 11 0 3 22 58 45 0 300 -69 .. .. .. 11 9 56 .. .. .. 12 3 4 Uncertainty in time = +/- 3 secs [Prediction of 2008 Feb 14.0] Data for the target star ------------------------ * name: HIP 24571 * constellation : Auriga * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 05 16 15.3584 DE: +29 21 23.722 * position source: mpos:UCAC2 pm:UCAC2 plx:HIP * standard error: RA,DE ["]: ( .011, .014 ) * V mag [mag]: 9.4 * B mag [mag]: 9.9 * Apparent position with proper motion RA(deg): 79.1955222941 DE(deg): 29.3680785736 * Equation of equinoxes (radians) : 0.000041507610988 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (3560) Chenqian approx. diameter [km]: 30 approx. diameter ["]: .013 distance from Earth [AU]: 3.06900 * orbital information: orbit source: Preston date of fit: 2008 Feb 13 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 655 number of rejected observations: 22 time covered by the observations: 1970 Oct 09 - 2008 Jan 11 1 sigma uncertainty ellipse (major, minor, PA): 0.034, 0.032, 96° remarks: * orbital elements for (3560) Chenqian : Mean anomaly = 61.29621298 deg Arg. of pericenter = 60.20948791 deg Long. of node = 325.37037852 deg Inclination = 9.27514427 deg Eccentricity = 0.11469613 Semimajor axis = 3.01952765 AU Perihelion dist = 2.67319951 AU Mag: H = 10.95, G = 0.15 Epoch of elements : MJD 54555.95500000 TDT (2008 Mar 30.955) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 Mar 30 3560 Chenqian 22h 55.1m UT 9.4 5 16 15.358 29 21 23.72HIP 24571 9.9 16.2 30 1.1 3.069 3.393 -3.79 -93.3988 29.358 -162.71 4.20 22.9178 0.02523 0.29846 15.48210 -1.32440 0.00542 0.00063 2000 60.1776072008 325.00000 60.209488325.370379 9.2751440.11469613 3.0195277 2.673199510.5 5.00.15 RATE 1.8784320 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.036 0.035 95 3.68 0.036 0 54510.5020080330__24571 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Feb 15, 00:24 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org