IOTA/IOTA-ES occultation update for (418) Alemannia / TYC 6210-00021-1 event on 2008 Jul 06, 01:39 UT Visible from NW Africa, SE Canada Summary ------- On 2008 Jul 06 UT, the 34 km diameter asteroid (418) Alemannia will occult a 11.0 mag star in the constellation Scorpius for observers along a path across NW Africa, SE Canada. In the case of an occultation, the combined light of the asteroid and the star will drop by 3.1 mag to 14.0 mag (the magnitude of the asteroid) for at most 5.1 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: 49 * date and approx. time of event: 2008 Jul 06, 01:32 - 2008 Jul 06, 01:46 UT * magnitude of target star: 11.0 * magnitude drop [mag]: 3.1 * estimated maximum duration [s]: 5.1 * Moon: 12 % sunlit, 102° distance * Sun: 142° distance * rough path description: NW Africa, SE Canada The occultation path -------------------- * approximate projected width [km]: 72 * 1 sigma uncertainty interval [path widths]: +/- 1.30 * 1 sigma uncertainty interval [seconds]: +/- 7.3 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .040 +/- .033) * 1 sigma uncertainty ellipse (major, minor, PA): ( .040", .033", 91° ) * approx speed of asteroid's shadow [km/s]: 6.7418 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 6210-00021-1 by 418 Alemannia on 2008 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 ' " Longitude Longitude Longitude Longitude - 69 13 24 59 0 0 1 46 37 12 177 -1 - 68 29 19 - 69 57 7 - 66 32 50 - 71 49 8 - 68 14 10 58 0 0 1 46 29 13 178 -2 - 67 30 46 - 68 57 11 - 65 36 5 - 70 47 24 - 67 13 3 57 0 0 1 46 20 14 179 -3 - 66 30 15 - 67 55 27 - 64 37 8 - 69 44 5 - 66 10 0 56 0 0 1 46 10 15 180 -4 - 65 27 44 - 66 51 54 - 63 35 57 - 68 39 9 - 65 5 0 55 0 0 1 46 0 16 181 -5 - 64 23 10 - 65 46 27 - 62 32 28 - 67 32 33 - 63 57 57 54 0 0 1 45 48 17 182 -7 - 63 16 28 - 64 39 3 - 61 26 38 - 66 24 11 - 62 48 47 53 0 0 1 45 36 18 183 -8 - 62 7 34 - 63 29 36 - 60 18 23 - 65 13 58 - 61 37 23 52 0 0 1 45 22 19 184 -9 - 60 56 21 - 62 18 1 - 59 7 35 - 64 1 49 - 60 23 39 51 0 0 1 45 8 19 185 -10 - 59 42 43 - 61 4 9 - 57 54 8 - 62 47 36 - 59 7 25 50 0 0 1 44 53 20 186 -11 - 58 26 30 - 59 47 54 - 56 37 52 - 61 31 13 - 57 48 33 49 0 0 1 44 37 21 188 -13 - 57 7 33 - 58 29 6 - 55 18 35 - 60 12 29 - 56 26 50 48 0 0 1 44 20 22 189 -14 - 55 45 38 - 57 7 32 - 53 56 4 - 58 51 14 - 55 2 2 47 0 0 1 44 1 23 190 -15 - 54 20 33 - 55 43 0 - 52 30 4 - 57 27 16 - 53 33 54 46 0 0 1 43 42 24 192 -17 - 52 51 59 - 54 15 15 - 51 0 13 - 56 0 21 - 52 2 5 45 0 0 1 43 21 25 194 -18 - 51 19 37 - 52 43 57 - 49 26 10 - 54 30 12 - 50 26 12 44 0 0 1 42 59 25 195 -19 - 49 43 1 - 51 8 44 - 47 47 24 - 52 56 30 - 48 45 46 43 0 0 1 42 36 26 197 -21 - 48 1 40 - 49 29 9 - 46 3 19 - 51 18 52 - 47 0 12 42 0 0 1 42 12 26 199 -22 - 46 14 57 - 47 44 39 - 44 13 9 - 49 36 48 - 45 8 44 41 0 0 1 41 45 27 201 -24 - 44 22 3 - 45 54 32 - 42 15 54 - 47 49 43 - 43 10 26 40 0 0 1 41 18 27 203 -25 - 42 21 55 - 43 57 54 - 40 10 13 - 45 56 54 - 41 4 0 39 0 0 1 40 48 28 205 -26 - 40 13 8 - 41 53 36 - 37 54 15 - 43 57 25 Latitude Latitude Latitude Latitude - 41 0 0 38 58 10 1 40 47 28 205 -26 39 21 19 38 35 22 40 23 14 37 37 33 - 40 0 0 38 31 14 1 40 33 28 206 -27 38 54 8 38 8 40 39 55 19 37 11 27 - 39 0 0 38 5 14 1 40 18 28 207 -28 38 27 53 37 42 54 39 28 23 36 46 14 - 38 0 0 37 40 9 1 40 4 28 208 -28 38 2 34 37 18 2 39 2 26 36 21 55 - 37 0 0 37 16 0 1 39 50 28 209 -29 37 38 12 36 54 6 38 37 28 35 58 28 - 36 0 0 36 52 46 1 39 36 28 210 -29 37 14 46 36 31 3 38 13 27 35 35 54 - 35 0 0 36 30 27 1 39 23 28 211 -30 36 52 15 36 8 55 37 50 24 35 14 12 - 34 0 0 36 9 2 1 39 9 28 212 -31 36 30 40 35 47 40 37 28 18 34 53 23 - 33 0 0 35 48 31 1 38 55 27 213 -31 36 9 59 35 27 20 37 7 9 34 33 26 - 32 0 0 35 28 55 1 38 41 27 214 -31 35 50 13 35 7 52 36 46 56 34 14 20 - 31 0 0 35 10 12 1 38 28 27 215 -32 35 31 21 34 49 18 36 27 40 33 56 7 - 30 0 0 34 52 22 1 38 15 27 216 -32 35 13 23 34 31 37 36 9 19 33 38 45 - 29 0 0 34 35 26 1 38 1 27 217 -33 34 56 20 34 14 48 35 51 53 33 22 15 - 28 0 0 34 19 24 1 37 48 26 218 -33 34 40 10 33 58 53 35 35 23 33 6 37 - 27 0 0 34 4 14 1 37 36 26 219 -33 34 24 54 33 43 50 35 19 48 32 51 50 - 26 0 0 33 49 58 1 37 23 26 220 -34 34 10 31 33 29 39 35 5 8 32 37 54 - 25 0 0 33 36 34 1 37 10 25 221 -34 33 57 1 33 16 21 34 51 22 32 24 49 - 24 0 0 33 24 3 1 36 58 25 221 -34 33 44 25 33 3 55 34 38 32 32 12 36 - 23 0 0 33 12 25 1 36 46 25 222 -34 33 32 42 32 52 22 34 26 35 32 1 14 - 22 0 0 33 1 39 1 36 34 24 223 -34 33 21 52 32 41 40 34 15 33 31 50 43 - 21 0 0 32 51 47 1 36 22 24 224 -35 33 11 56 32 31 51 34 5 26 31 41 3 - 20 0 0 32 42 47 1 36 10 23 225 -35 33 2 52 32 22 55 33 56 13 31 32 14 - 19 0 0 32 34 39 1 35 59 23 226 -35 32 54 42 32 14 50 33 47 54 31 24 17 - 18 0 0 32 27 25 1 35 48 22 226 -35 32 47 24 32 7 38 33 40 29 31 17 11 - 17 0 0 32 21 3 1 35 37 22 227 -35 32 41 0 32 1 18 33 33 59 31 10 56 - 16 0 0 32 15 34 1 35 26 21 228 -35 32 35 30 31 55 51 33 28 24 31 5 33 - 15 0 0 32 10 58 1 35 16 21 229 -35 32 30 52 31 51 16 33 23 43 31 1 2 - 14 0 0 32 7 15 1 35 6 20 229 -35 32 27 8 31 47 34 33 19 56 30 57 22 - 13 0 0 32 4 25 1 34 56 20 230 -35 32 24 18 31 44 44 33 17 4 30 54 33 - 12 0 0 32 2 28 1 34 46 19 231 -35 32 22 21 31 42 48 33 15 7 30 52 37 - 11 0 0 32 1 25 1 34 37 18 231 -34 32 21 18 31 41 45 33 14 6 30 51 33 - 10 0 0 32 1 16 1 34 28 18 232 -34 32 21 10 31 41 34 33 13 59 30 51 21 - 9 0 0 32 2 0 1 34 19 17 233 -34 32 21 55 31 42 18 33 14 48 30 52 2 - 8 0 0 32 3 39 1 34 11 17 233 -34 32 23 36 31 43 55 33 16 32 30 53 35 - 7 0 0 32 6 12 1 34 3 16 234 -33 32 26 11 31 46 26 33 19 13 30 56 1 - 6 0 0 32 9 39 1 33 55 15 235 -33 32 29 41 31 49 51 33 22 50 30 59 20 - 5 0 0 32 14 2 1 33 48 14 235 -33 32 34 6 31 54 11 33 27 23 31 3 33 - 4 0 0 32 19 19 1 33 41 14 236 -32 32 39 27 31 59 25 33 32 53 31 8 40 - 3 0 0 32 25 32 1 33 34 13 237 -32 32 45 44 32 5 35 33 39 21 31 14 40 - 2 0 0 32 32 42 1 33 28 12 237 -32 32 52 57 32 12 40 33 46 46 31 21 35 - 1 0 0 32 40 47 1 33 22 11 238 -31 33 1 7 32 20 40 33 55 9 31 29 24 0 0 0 32 49 49 1 33 16 11 238 -31 33 10 14 32 29 37 34 4 30 31 38 9 1 0 0 32 59 48 1 33 11 10 239 -30 33 20 19 32 39 31 34 14 51 31 47 49 2 0 0 33 10 44 1 33 6 9 240 -30 33 31 22 32 50 21 34 26 11 31 58 24 3 0 0 33 22 39 1 33 1 8 240 -29 33 43 23 33 2 9 34 38 31 32 9 56 4 0 0 33 35 32 1 32 57 7 241 -29 33 56 23 33 14 55 34 51 52 32 22 25 5 0 0 33 49 23 1 32 54 7 241 -28 34 10 23 33 28 39 35 6 13 32 35 50 6 0 0 34 4 15 1 32 50 6 242 -27 34 25 23 33 43 22 35 21 37 32 50 13 7 0 0 34 20 6 1 32 48 5 242 -27 34 41 23 33 59 5 35 38 2 .. .. .. 8 0 0 34 36 58 1 32 45 4 243 -26 34 58 25 34 15 47 35 55 31 .. .. .. 9 0 0 34 54 51 1 32 43 3 243 -25 35 16 28 34 33 30 36 14 4 .. .. .. 10 0 0 35 13 46 1 32 42 2 244 -25 35 35 34 34 52 15 36 33 41 .. .. .. 11 0 0 35 33 43 1 32 41 1 245 -24 35 55 44 35 12 1 36 54 23 .. .. .. 12 0 0 35 54 44 1 32 40 1 245 -23 36 16 57 35 32 49 .. .. .. .. .. .. Uncertainty in time = +/- 8 secs [Prediction of 2008 Jul 2.0] Data for the target star ------------------------ * name: TYC 6210-00021-1 * constellation : Scorpius * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 16 20 07.3135 DE: -19 31 17.777 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .034, .030 ) * V mag [mag]: 11.0 * B mag [mag]: 12.2 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (418) Alemannia approx. diameter [km]: 34 approx. diameter ["]: .026 distance from Earth [AU]: 1.81400 * orbital information: orbit source: Preston date of fit: 2008 Jul 02 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 704 number of rejected observations: 90 time covered by the observations: 1905 Dec 17 - 2008 Jun 03 1 sigma uncertainty ellipse (major, minor, PA): 0.022, 0.014, 92° remarks: * orbital elements for (418) Alemannia : Mean anomaly = 258.13161480 deg Arg. of pericenter = 125.62669774 deg Long. of node = 249.09197866 deg Inclination = 6.82401197 deg Eccentricity = 0.11921576 Semimajor axis = 2.59332297 AU Perihelion dist = 2.28415801 AU Mag: H = 9.72, G = 0.15 Epoch of elements : MJD 54653.06900000 TDT (2008 Jul 06.069) ------ occelmnt file for Occult BEGIN ----------------------------------- 2008 Jul 6 418 Alemannia 1h 40.0m UT 11.0 16 20 7.313-19 31 17.78TYC 6210-00021-1 12.2 14.0 34 5.1 1.814 -1.194 7.38 -64.3962 -19.523 156.18 22.66 1.6673 0.35285 0.80961 -3.48701 1.52340 0.00333 -0.00072 2000 257.4073192008 7 3.00000125.626698249.091979 6.8240120.11921576 2.5933230 2.2841580 9.8 5.00.15 RATE 2.3600390 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.040 0.033 91 2.30 0.034 0 54649.5020080706_0021-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Jul 02, 19:03 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org