IOTA/IOTA-ES occultation update for (61) Danae / TYC 8361-00947-1 event on 2009 Jul 06, 05:42 UT Visible from Summary ------- On 2009 Jul 06 UT, the 77 km diameter asteroid (61) Danae will occult a 10.5 mag star in the constellation Telescopium for observers along a path across . In the case of an occultation, the combined light of the asteroid and the star will drop by 1.6 mag to 11.8 mag (the magnitude of the asteroid) for at most 6.6 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: 84 * date and approx. time of event: 2009 Jul 06, 05:39 - 2009 Jul 06, 05:45 UT * magnitude of target star: 10.5 * magnitude drop [mag]: 1.6 * estimated maximum duration [s]: 6.6 * Moon: 99 % sunlit, 21° distance * Sun: 153° distance * rough path description: The occultation path -------------------- * approximate projected width [km]: 228 * 1 sigma uncertainty interval [path widths]: +/- 0.61 * 1 sigma uncertainty interval [seconds]: +/- 3.4 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .043 +/- .035) * 1 sigma uncertainty ellipse (major, minor, PA): ( .043", .035", 86° ) * approx speed of asteroid's shadow [km/s]: 11.6342 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 8361-00947-1 by 61 Danae on 2009 Jul 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 ' " Latitude Latitude Latitude Latitude - 94 0 0 39 3 2 5 45 11 4 183 -28 .. .. .. 34 39 42 .. .. .. 31 38 10 - 93 0 0 35 28 58 5 45 1 7 183 -32 .. .. .. 32 38 18 .. .. .. 30 5 27 - 92 0 0 33 17 48 5 44 52 9 184 -34 36 37 44 30 59 37 .. .. .. 28 44 29 - 91 0 0 31 35 6 5 44 42 11 185 -36 34 7 59 29 35 14 .. .. .. 27 32 24 - 90 0 0 30 8 52 5 44 33 12 185 -37 32 18 30 28 21 7 36 7 25 26 27 26 - 89 0 0 28 54 0 5 44 23 13 186 -38 30 49 6 27 14 59 33 50 44 25 28 24 - 88 0 0 27 47 43 5 44 14 14 187 -40 29 32 40 26 15 22 32 9 16 24 34 28 - 87 0 0 26 48 21 5 44 4 15 187 -41 28 25 45 25 21 15 30 46 11 23 45 2 - 86 0 0 25 54 45 5 43 55 16 188 -42 27 26 18 24 31 55 29 35 15 22 59 36 - 85 0 0 25 6 9 5 43 45 17 189 -42 26 33 0 23 46 49 28 33 19 22 17 49 - 84 0 0 24 21 56 5 43 36 17 190 -43 25 44 57 23 5 34 27 38 30 21 39 23 - 83 0 0 23 41 40 5 43 26 18 190 -44 25 1 29 22 27 48 26 49 36 21 4 3 - 82 0 0 23 5 0 5 43 17 18 191 -44 24 22 8 21 53 16 26 5 48 20 31 38 - 81 0 0 22 31 38 5 43 7 19 192 -45 23 46 29 21 21 46 25 26 28 20 1 57 - 80 0 0 22 1 22 5 42 58 19 192 -45 23 14 17 20 53 5 24 51 9 19 34 53 - 79 0 0 21 34 1 5 42 49 19 193 -46 22 45 15 20 27 6 24 19 31 19 10 17 - 78 0 0 21 9 25 5 42 40 19 194 -46 22 19 13 20 3 41 23 51 15 18 48 5 - 77 0 0 20 47 26 5 42 30 20 194 -46 21 56 1 19 42 44 23 26 10 18 28 10 - 76 0 0 20 27 58 5 42 21 20 195 -46 21 35 30 19 24 9 23 4 4 18 10 30 - 75 0 0 20 10 57 5 42 12 20 196 -46 21 17 36 19 7 52 22 44 49 17 54 59 - 74 0 0 19 56 17 5 42 3 20 196 -46 21 2 12 18 53 50 22 28 19 17 41 36 - 73 0 0 19 43 55 5 41 54 20 197 -46 20 49 14 18 41 59 22 14 26 17 30 17 - 72 0 0 19 33 48 5 41 46 19 198 -46 20 38 38 18 32 17 22 3 8 17 21 1 - 71 0 0 19 25 55 5 41 37 19 198 -46 20 30 23 18 24 42 21 54 20 17 13 45 - 70 0 0 19 20 13 5 41 28 19 199 -46 20 24 26 18 19 13 21 48 1 17 8 29 - 69 0 0 19 16 41 5 41 20 19 200 -46 20 20 45 18 15 48 21 44 7 17 5 13 - 68 0 0 19 15 19 5 41 12 19 200 -45 20 19 21 18 14 28 21 42 40 17 3 54 - 67 0 0 19 16 6 5 41 3 18 201 -45 20 20 12 18 15 12 21 43 37 17 4 35 - 66 0 0 19 19 4 5 40 55 18 201 -45 20 23 20 18 18 0 21 47 1 17 7 13 - 65 0 0 19 24 12 5 40 47 17 202 -44 20 28 46 18 22 54 21 52 51 17 11 52 - 64 0 0 19 31 32 5 40 40 17 203 -44 20 36 30 18 29 54 22 1 11 17 18 31 - 63 0 0 19 41 7 5 40 32 16 203 -43 20 46 36 18 39 3 22 12 4 17 27 12 - 62 0 0 19 52 59 5 40 25 16 204 -42 20 59 7 18 50 22 22 25 32 17 37 56 - 61 0 0 20 7 11 5 40 17 15 204 -42 21 14 6 19 3 54 22 41 42 17 50 47 - 60 0 0 20 23 47 5 40 10 15 205 -41 21 31 38 19 19 43 23 0 39 18 5 47 - 59 0 0 20 42 53 5 40 4 14 205 -40 21 51 49 19 37 52 23 22 31 18 23 0 - 58 0 0 21 4 33 5 39 57 13 206 -40 22 14 46 19 58 28 23 47 27 18 42 29 - 57 0 0 21 28 54 5 39 51 13 206 -39 22 40 38 20 21 34 24 15 40 19 4 19 - 56 0 0 21 56 6 5 39 45 12 207 -38 23 9 36 20 47 19 24 47 23 19 28 37 - 55 0 0 22 26 18 5 39 39 11 207 -37 23 41 51 21 15 51 25 22 56 19 55 27 - 54 0 0 22 59 43 5 39 33 10 208 -36 24 17 40 21 47 19 26 2 40 20 25 0 - 53 0 0 23 36 34 5 39 28 9 208 -35 24 57 23 22 21 55 26 47 8 20 57 22 - 52 0 0 24 17 12 5 39 24 8 209 -34 25 41 25 22 59 53 27 37 1 21 32 46 - 51 0 0 25 2 0 5 39 19 7 209 -33 26 30 20 23 41 32 28 33 15 22 11 25 - 50 0 0 25 51 26 5 39 16 6 210 -32 27 24 51 24 27 12 29 37 14 22 53 34 - 49 0 0 26 46 13 5 39 12 5 210 -30 28 26 1 25 17 23 30 51 13 23 39 34 - 48 0 0 27 47 14 5 39 10 3 210 -29 29 35 23 26 12 41 .. .. .. .. .. .. - 47 0 0 28 55 50 5 39 8 2 211 -28 30 55 25 27 13 56 .. .. .. .. .. .. - 46 0 0 30 14 0 5 39 7 0 211 -26 .. .. .. 28 22 18 .. .. .. .. .. .. Uncertainty in time = +/- 5 secs [Prediction of 2008 Mar 20.0] Data for the target star ------------------------ * name: TYC 8361-00947-1 * constellation : Telescopium * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 18 10 14.2253 DE: -47 23 50.566 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .031, .031 ) * V mag [mag]: 10.5 * B mag [mag]: 12.3 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (61) Danae approx. diameter [km]: 77 approx. diameter ["]: .059 distance from Earth [AU]: 1.80800 * orbital information: orbit source: Preston date of fit: 2008 Mar 20 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 653 number of rejected observations: 67 time covered by the observations: 1900 Mar 29 - 2008 Jan 26 1 sigma uncertainty ellipse (major, minor, PA): 0.031, 0.016, 83° remarks: * orbital elements for (61) Danae : Mean anomaly = 305.46346465 deg Arg. of pericenter = 13.64750167 deg Long. of node = 333.76893981 deg Inclination = 18.22552302 deg Eccentricity = 0.16869409 Semimajor axis = 2.98145403 AU Perihelion dist = 2.47850035 AU Mag: H = 7.61, G = 0.15 Epoch of elements : MJD 55018.23800000 TDT (2009 Jul 06.238) ------ occelmnt file for Occult BEGIN ----------------------------------- 2009 Jul 6 61 Danae 5h 42.2m UT 10.5 18 10 14.225-47 23 50.57TYC 8361-00947-1 12.3 11.8 77 6.6 1.808 -2.911 12.08 -97.3322 -47.400 95.64 22.67 5.7031 0.35567 0.87152 -6.07936 2.48250 0.00113 0.00221 2000 303.8862762009 628.00000 13.647502333.768940 18.2255230.16869409 2.9814540 2.4785004 7.7 5.00.15 RATE 1.9145290 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.043 0.035 86 1.61 0.036 0 54545.5020090706_0947-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Mar 20, 10:22 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org