IOTA/IOTA-ES occultation update for (1922) Zulu / TYC 3141-03313-1 event on 2008 Aug 25, 19:40 UT Visible from Russia, Africa Summary ------- On 2008 Aug 25 UT, the 12 km diameter asteroid (1922) Zulu will occult a 9.7 mag star in the constellation Cygnus for observers along a path across Russia, Africa. In the case of an occultation, the combined light of the asteroid and the star will drop by 6.0 mag to 15.7 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: 12 * date and approx. time of event: 2008 Aug 25, 19:33 - 2008 Aug 25, 19:50 UT * midpoint of event [JD]: 2454704.319625 * magnitude of target star: 9.7 * magnitude drop [mag]: 6.0 * estimated maximum duration [s]: 1.1 * Moon: 30 % sunlit, 106° distance * Sun: 119° distance * rough path description: Russia, Africa The occultation path -------------------- * approximate projected width [km]: 12 * 1 sigma uncertainty interval [path widths]: +/- 5.46 * 1 sigma uncertainty interval [seconds]: +/- 4.5 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .065 +/- .048) * 1 sigma uncertainty ellipse (major, minor, PA): ( .066", .047", 101° ) * approx speed of asteroid's shadow [km/s]: 10.6118 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 3141-03313-1 by 1922 Zulu on 2008 Aug 25 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 25 45 57 -49 0 0 19 50 15 1 1 -41 25 41 1 25 50 53 24 47 10 26 44 47 25 46 58 -48 0 0 19 50 15 2 1 -41 25 42 7 25 51 48 24 49 19 26 44 39 25 48 3 -47 0 0 19 50 15 3 1 -42 25 43 18 25 52 47 24 51 29 26 44 39 25 49 12 -46 0 0 19 50 14 4 1 -42 25 44 33 25 53 52 24 53 40 26 44 47 25 50 26 -45 0 0 19 50 13 5 1 -43 25 45 51 25 55 1 24 55 52 26 45 2 25 51 45 -44 0 0 19 50 12 6 0 -44 25 47 15 25 56 15 24 58 6 26 45 25 25 53 7 -43 0 0 19 50 11 7 0 -44 25 48 42 25 57 33 25 0 21 26 45 56 25 54 35 -42 0 0 19 50 10 8 0 -45 25 50 13 25 58 56 25 2 38 26 46 33 25 56 6 -41 0 0 19 50 8 9 0 -45 25 51 48 26 0 23 25 4 57 26 47 17 25 57 41 -40 0 0 19 50 7 10 0 -46 25 53 28 26 1 55 25 7 18 26 48 7 25 59 21 -39 0 0 19 50 5 11 0 -46 25 55 11 26 3 31 25 9 40 26 49 4 26 1 5 -38 0 0 19 50 3 12 0 -47 25 56 58 26 5 12 25 12 5 26 50 7 26 2 53 -37 0 0 19 50 0 13 0 -47 25 58 50 26 6 57 25 14 32 26 51 16 26 4 45 -36 0 0 19 49 58 14 0 -48 26 0 45 26 8 46 25 17 1 26 52 32 26 6 42 -35 0 0 19 49 55 15 0 -48 26 2 44 26 10 39 25 19 32 26 53 53 26 8 42 -34 0 0 19 49 53 16 0 -49 26 4 47 26 12 37 25 22 6 26 55 20 26 10 46 -33 0 0 19 49 50 17 0 -49 26 6 54 26 14 38 25 24 42 26 56 52 26 12 55 -32 0 0 19 49 47 18 0 -50 26 9 5 26 16 44 25 27 21 26 58 30 26 15 7 -31 0 0 19 49 43 19 0 -50 26 11 20 26 18 54 25 30 2 27 0 14 26 17 24 -30 0 0 19 49 40 20 0 -51 26 13 39 26 21 8 25 32 46 27 2 3 26 19 44 -29 0 0 19 49 36 21 0 -51 26 16 2 26 23 27 25 35 32 27 3 57 26 22 9 -28 0 0 19 49 33 22 0 -51 26 18 28 26 25 49 25 38 22 27 5 57 26 24 37 -27 0 0 19 49 29 23 0 -52 26 20 59 26 28 15 25 41 14 27 8 2 26 27 9 -26 0 0 19 49 24 24 0 -52 26 23 33 26 30 46 25 44 8 27 10 12 26 29 46 -25 0 0 19 49 20 25 0 -52 26 26 11 26 33 21 25 47 6 27 12 27 26 32 26 -24 0 0 19 49 16 26 0 -53 26 28 53 26 35 59 25 50 6 27 14 48 26 35 11 -23 0 0 19 49 11 27 0 -53 26 31 39 26 38 42 25 53 10 27 17 13 26 37 59 -22 0 0 19 49 6 28 0 -53 26 34 29 26 41 29 25 56 16 27 19 44 26 40 51 -21 0 0 19 49 1 29 0 -53 26 37 23 26 44 20 25 59 25 27 22 19 26 43 48 -20 0 0 19 48 56 30 0 -54 26 40 21 26 47 15 26 2 38 27 25 0 26 46 48 -19 0 0 19 48 51 31 0 -54 26 43 22 26 50 14 26 5 53 27 27 45 26 49 53 -18 0 0 19 48 46 32 0 -54 26 46 28 26 53 17 26 9 12 27 30 35 26 53 1 -17 0 0 19 48 40 33 0 -54 26 49 37 26 56 25 26 12 33 27 33 30 26 56 13 -16 0 0 19 48 34 34 360 -54 26 52 51 26 59 36 26 15 58 27 36 31 26 59 30 -15 0 0 19 48 28 35 360 -54 26 56 8 27 2 52 26 19 26 27 39 36 27 2 50 -14 0 0 19 48 22 36 360 -54 26 59 29 27 6 11 26 22 57 27 42 45 27 6 15 -13 0 0 19 48 16 37 360 -54 27 2 55 27 9 35 26 26 31 27 46 0 27 9 44 -12 0 0 19 48 10 38 360 -54 27 6 24 27 13 3 26 30 9 27 49 20 27 13 16 -11 0 0 19 48 3 39 360 -54 27 9 58 27 16 35 26 33 50 27 52 44 27 16 53 -10 0 0 19 47 57 40 360 -54 27 13 35 27 20 11 26 37 34 27 56 14 27 20 34 - 9 0 0 19 47 50 41 360 -54 27 17 17 27 23 52 26 41 22 27 59 48 27 24 19 - 8 0 0 19 47 43 42 360 -54 27 21 3 27 27 36 26 45 13 28 3 27 27 28 9 - 7 0 0 19 47 36 43 360 -54 27 24 52 27 31 25 26 49 8 28 7 11 27 32 2 - 6 0 0 19 47 29 44 360 -54 27 28 46 27 35 18 26 53 6 28 11 0 27 36 0 - 5 0 0 19 47 22 45 360 -54 27 32 44 27 39 16 26 57 8 28 14 55 27 40 2 - 4 0 0 19 47 14 46 360 -54 27 36 47 27 43 18 27 1 13 28 18 54 27 44 9 - 3 0 0 19 47 7 47 359 -54 27 40 54 27 47 24 27 5 22 28 22 58 27 48 20 - 2 0 0 19 46 59 48 359 -53 27 45 5 27 51 35 27 9 34 28 27 7 27 52 35 - 1 0 0 19 46 51 49 359 -53 27 49 20 27 55 50 27 13 50 28 31 21 27 56 55 0 0 0 19 46 43 50 359 -53 27 53 40 28 0 10 27 18 10 28 35 41 28 1 19 1 0 0 19 46 35 51 359 -53 27 58 4 28 4 34 27 22 34 28 40 5 28 5 48 2 0 0 19 46 27 52 359 -52 28 2 32 28 9 3 27 27 2 28 44 35 28 10 21 3 0 0 19 46 19 53 359 -52 28 7 6 28 13 36 27 31 33 28 49 11 28 14 59 4 0 0 19 46 11 54 359 -52 28 11 44 28 18 15 27 36 9 28 53 51 28 19 42 5 0 0 19 46 2 55 359 -51 28 16 26 28 22 58 27 40 48 28 58 38 28 24 30 6 0 0 19 45 54 56 359 -51 28 21 13 28 27 46 27 45 32 29 3 29 28 29 22 7 0 0 19 45 45 57 359 -51 28 26 6 28 32 39 27 50 20 29 8 27 28 34 20 8 0 0 19 45 36 58 359 -50 28 31 3 28 37 37 27 55 12 29 13 29 28 39 22 9 0 0 19 45 27 59 359 -50 28 36 5 28 42 40 28 0 8 29 18 38 28 44 30 10 0 0 19 45 18 60 358 -49 28 41 12 28 47 48 28 5 9 29 23 53 28 49 43 11 0 0 19 45 9 61 358 -49 28 46 24 28 53 2 28 10 14 29 29 14 28 55 1 12 0 0 19 45 0 62 358 -48 28 51 42 28 58 21 28 15 24 29 34 41 29 0 25 13 0 0 19 44 51 63 358 -48 28 57 5 29 3 45 28 20 39 29 40 14 29 5 54 14 0 0 19 44 41 64 358 -47 29 2 33 29 9 16 28 25 58 29 45 53 29 11 29 15 0 0 19 44 32 65 358 -47 29 8 7 29 14 52 28 31 22 29 51 39 29 17 10 16 0 0 19 44 22 66 358 -46 29 13 47 29 20 34 28 36 51 29 57 32 29 22 57 17 0 0 19 44 13 67 357 -46 29 19 33 29 26 22 28 42 26 30 3 32 29 28 51 18 0 0 19 44 3 68 357 -45 29 25 25 29 32 16 28 48 5 30 9 38 29 34 50 19 0 0 19 43 54 69 357 -45 29 31 24 29 38 17 28 53 51 30 15 52 29 40 56 20 0 0 19 43 44 70 357 -44 29 37 28 29 44 24 28 59 41 30 22 14 29 47 9 21 0 0 19 43 34 71 356 -44 29 43 40 29 50 38 29 5 38 30 28 43 29 53 29 22 0 0 19 43 24 71 356 -43 29 49 58 29 56 59 29 11 40 30 35 20 29 59 55 23 0 0 19 43 14 72 356 -42 29 56 23 30 3 28 29 17 49 30 42 5 30 6 30 24 0 0 19 43 4 73 355 -42 30 2 56 30 10 3 29 24 4 30 48 58 30 13 12 25 0 0 19 42 54 74 355 -41 30 9 36 30 16 47 29 30 25 30 56 1 30 20 1 26 0 0 19 42 44 75 354 -41 30 16 24 30 23 39 29 36 54 31 3 12 30 26 59 27 0 0 19 42 34 76 353 -40 30 23 20 30 30 39 29 43 29 31 10 33 30 34 6 28 0 0 19 42 23 77 353 -39 30 30 25 30 37 47 29 50 12 31 18 4 30 41 22 29 0 0 19 42 13 78 352 -39 30 37 38 30 45 5 29 57 2 31 25 44 30 48 46 30 0 0 19 42 3 79 351 -38 30 45 1 30 52 32 30 4 0 31 33 36 30 56 21 31 0 0 19 41 53 80 349 -37 30 52 33 31 0 9 30 11 7 31 41 38 31 4 5 32 0 0 19 41 42 81 348 -37 31 0 15 31 7 56 30 18 22 31 49 52 31 12 0 33 0 0 19 41 32 82 345 -36 31 8 8 31 15 53 30 25 47 31 58 18 31 20 7 34 0 0 19 41 21 83 343 -35 31 16 11 31 24 2 30 33 20 32 6 57 31 28 24 35 0 0 19 41 11 84 339 -35 31 24 26 31 32 23 30 41 4 32 15 49 31 36 54 36 0 0 19 41 1 84 334 -34 31 32 53 31 40 56 30 48 58 32 24 54 31 45 37 37 0 0 19 40 50 85 327 -33 31 41 32 31 49 42 30 57 3 32 34 15 31 54 33 38 0 0 19 40 40 86 317 -32 31 50 25 31 58 41 31 5 20 32 43 51 32 3 44 39 0 0 19 40 29 86 301 -32 31 59 32 32 7 55 31 13 49 32 53 43 32 13 9 40 0 0 19 40 19 86 281 -31 32 8 54 32 17 24 31 22 31 33 3 52 32 22 50 41 0 0 19 40 8 86 258 -30 32 18 31 32 27 9 31 31 26 33 14 20 32 32 49 42 0 0 19 39 58 86 240 -30 32 28 26 32 37 12 31 40 36 33 25 6 32 43 5 43 0 0 19 39 47 85 228 -29 32 38 37 32 47 32 31 50 1 33 36 14 32 53 40 44 0 0 19 39 37 84 219 -28 32 49 8 32 58 12 31 59 43 33 47 43 33 4 35 45 0 0 19 39 26 84 213 -27 32 59 59 33 9 12 32 9 42 33 59 35 33 15 52 46 0 0 19 39 16 83 209 -27 33 11 11 33 20 34 32 19 59 34 11 52 33 27 32 47 0 0 19 39 5 82 206 -26 33 22 45 33 32 19 32 30 37 34 24 35 33 39 37 48 0 0 19 38 55 81 204 -25 33 34 45 33 44 30 32 41 35 34 37 46 33 52 8 49 0 0 19 38 44 80 202 -24 33 47 10 33 57 7 32 52 56 34 51 28 34 5 8 50 0 0 19 38 34 79 201 -24 34 0 4 34 10 13 33 4 42 35 5 43 34 18 39 51 0 0 19 38 24 78 200 -23 34 13 28 34 23 50 33 16 54 35 20 32 34 32 43 52 0 0 19 38 13 77 199 -22 34 27 24 34 38 1 33 29 35 35 36 0 34 47 22 53 0 0 19 38 3 76 198 -21 34 41 57 34 52 48 33 42 46 35 52 9 35 2 41 54 0 0 19 37 53 75 197 -21 34 57 7 35 8 14 33 56 31 36 9 2 35 18 41 55 0 0 19 37 42 74 197 -20 35 13 0 35 24 23 34 10 52 36 26 43 35 35 28 56 0 0 19 37 32 73 197 -19 35 29 37 35 41 19 34 25 52 36 45 17 35 53 5 57 0 0 19 37 22 72 196 -18 35 47 5 35 59 6 34 41 36 37 4 49 36 11 38 58 0 0 19 37 12 72 196 -17 36 5 27 36 17 48 34 58 7 37 25 24 36 31 10 59 0 0 19 37 2 71 196 -17 36 24 49 36 37 32 35 15 29 37 47 8 36 51 50 60 0 0 19 36 52 70 196 -16 36 45 17 36 58 23 35 33 49 38 10 9 37 13 43 61 0 0 19 36 42 69 196 -15 37 6 57 37 20 29 35 53 13 38 34 34 37 36 59 62 0 0 19 36 32 68 196 -14 37 29 59 37 43 58 36 13 46 39 0 33 38 1 45 63 0 0 19 36 22 67 196 -14 37 54 31 38 9 0 36 35 38 39 28 17 38 28 14 64 0 0 19 36 12 66 196 -13 38 20 44 38 35 45 36 58 57 39 57 58 38 56 38 65 0 0 19 36 3 65 196 -12 38 48 50 39 4 26 37 23 54 40 29 51 39 27 11 66 0 0 19 35 53 64 196 -11 39 19 4 39 35 18 37 50 43 41 4 13 Latitude Latitude Latitude Latitude 40 0 0 66 59 41 19 35 43 63 197 -10 67 14 29 66 44 54 69 56 42 64 3 57 41 0 0 68 37 34 19 35 28 61 197 -9 68 51 25 68 23 43 71 23 16 65 52 53 42 0 0 70 3 2 19 35 15 59 198 -8 70 16 3 69 50 2 72 38 39 67 28 16 43 0 0 71 18 10 19 35 3 58 199 -7 71 30 26 71 5 54 73 44 44 68 52 16 44 0 0 72 24 36 19 34 53 57 200 -6 72 36 11 72 13 1 74 43 3 70 6 42 45 0 0 73 23 41 19 34 44 56 200 -5 73 34 40 73 12 42 75 34 49 71 12 59 46 0 0 74 16 30 19 34 36 55 201 -4 74 26 55 74 6 4 76 21 2 72 12 19 47 0 0 75 3 56 19 34 29 54 202 -4 75 13 52 74 54 0 77 2 30 73 5 40 48 0 0 75 46 45 19 34 22 53 203 -3 75 56 14 75 37 17 77 39 53 73 53 53 49 0 0 76 25 34 19 34 16 53 204 -3 76 34 38 76 16 30 78 13 43 74 37 36 50 0 0 77 0 52 19 34 11 52 205 -2 77 9 33 76 52 11 78 44 30 75 17 24 51 0 0 77 33 6 19 34 6 52 206 -2 77 41 26 77 24 46 79 12 34 75 53 46 52 0 0 78 2 37 19 34 2 51 207 -1 78 10 39 77 54 36 79 38 16 76 27 5 53 0 0 78 29 45 19 33 58 51 207 -1 78 37 29 78 22 2 80 1 53 76 57 44 54 0 0 78 54 46 19 33 54 50 208 0 79 2 13 78 47 19 80 23 37 77 25 59 55 0 0 79 17 52 19 33 51 50 209 0 79 25 4 79 10 40 80 43 42 77 52 6 Uncertainty in time = +/- 6 secs [Prediction of 2008 Jul 25.0] Data for the target star ------------------------ * name: TYC 3141-03313-1 * constellation : Cygnus * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 19 53 40.1268 DE: +40 12 28.997 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .016, .016 ) * V mag [mag]: 9.7 * B mag [mag]: 11.0 * Apparent position with proper motion RA(deg): 298.4993246653 DE(deg): 40.2333302698 * Equation of equinoxes (radians) : 0.000054683700031 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (1922) Zulu approx. diameter [km]: 12 approx. diameter ["]: .012 distance from Earth [AU]: 1.39100 * orbital information: orbit source: Preston date of fit: 2008 Jul 22 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 574 number of rejected observations: 12 time covered by the observations: 1949 Apr 25 - 2008 Jul 17 1 sigma uncertainty ellipse (major, minor, PA): 0.064, 0.044, 102° remarks: * orbital elements for (1922) Zulu : Mean anomaly = 23.54028679 deg Arg. of pericenter = 31.57224688 deg Long. of node = 226.53776280 deg Inclination = 35.42642491 deg Eccentricity = 0.48076070 Semimajor axis = 3.23814981 AU Perihelion dist = 1.68137463 AU Mag: H = 12.05, G = 0.15 Epoch of elements : MJD 54703.82000000 TDT (2008 Aug 25.820) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 Aug 25 1922 Zulu 19h 40.3m UT 9.7 19 53 40.127 40 12 29.00TYC 3141-03313-1 11.1 15.7 12 1.1 1.391 -0.170 -37.82 28.9138 40.219 -114.59 10.42 19.6710 0.04356 -0.00158 -0.31197 -5.98148 0.00303 -0.00342 2000 22.8941542008 822.00000 31.572247226.537763 35.4264250.48076070 3.2381498 1.681374612.2 5.00.15 RATE 1.6914480 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.066 0.047 101 6.46 0.066 0 54672.5020080825_3313-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Jul 25, 05:31 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org