IOTA/IOTA-ES occultation update for (141) Lumen / TYC 5233-01669-1 event on 2012 Dec 20, 07:26 UT Visible from S Pacific Ocean Summary ------- On 2012 Dec 20 UT, the 145 km diameter asteroid (141) Lumen will occult a 11.2 mag star in the constellation Aquarius for observers along a path across S Pacific Ocean. In the case of an occultation, the combined light of the asteroid and the star will drop by 1.8 mag to 12.7 mag (the magnitude of the asteroid) for at most 4.9 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: 99 * date and approx. time of event: 2012 Dec 20, 07:27 - 2012 Dec 20, 07:29 UT * geocentric midpoint of event [JD]: 2456281.8101375 * magnitude of target star: 11.2 * magnitude drop [mag]: 1.8 * estimated maximum duration [s]: 4.9 * Moon: 51 % sunlit, 20° distance * Sun: 71° distance * rough path description: S Pacific Ocean The occultation path -------------------- * approximate projected width [km]: 201 * 1 sigma uncertainty interval [path widths]: +/- 0.27 * 1 sigma uncertainty interval [seconds]: +/- 1.5 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .028 +/- .024) * 1 sigma uncertainty ellipse (major, minor, PA): ( .028", .024", 79° ) * approx speed of asteroid's shadow [km/s]: 29.4818 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 5233-01669-1 by 141 Lumen on 2012 Dec 20 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 174 0 0 -32 53 58 7 27 32 42 306 0 -33 55 10 -31 53 53 -34 28 43 -31 21 54 175 0 0 -32 29 45 7 27 35 42 304 -1 -33 30 47 -31 29 52 -34 4 14 -30 57 58 176 0 0 -32 5 51 7 27 38 41 303 -2 -33 6 41 -31 6 8 -33 40 2 -30 34 19 177 0 0 -31 42 16 7 27 42 41 302 -3 -32 42 55 -30 42 43 -33 16 9 -30 11 0 178 0 0 -31 18 59 7 27 45 40 301 -4 -32 19 27 -30 19 37 -32 52 35 -29 47 59 179 0 0 -30 56 3 7 27 48 40 299 -5 -31 56 20 -29 56 51 -32 29 21 -29 25 19 180 0 0 -30 33 27 7 27 51 39 298 -6 -31 33 33 -29 34 26 -32 6 28 -29 2 59 -179 0 0 -30 11 12 7 27 54 38 297 -7 -31 11 7 -29 12 21 -31 43 56 -28 41 0 -178 0 0 -29 49 19 7 27 57 38 296 -8 -30 49 3 -28 50 39 -31 21 46 -28 19 22 -177 0 0 -29 27 48 7 28 0 37 295 -9 -30 27 21 -28 29 18 -30 59 58 -27 58 7 -176 0 0 -29 6 40 7 28 3 37 294 -10 -30 6 3 -28 8 20 -30 38 34 -27 37 15 -175 0 0 -28 45 56 7 28 6 36 293 -11 -29 45 7 -27 47 46 -30 17 33 -27 16 46 -174 0 0 -28 25 35 7 28 9 35 292 -11 -29 24 36 -27 27 35 -29 56 56 -26 56 40 -173 0 0 -28 5 39 7 28 12 34 291 -12 -29 4 30 -27 7 49 -29 36 43 -26 36 59 -172 0 0 -27 46 8 7 28 15 34 290 -13 -28 44 48 -26 48 28 -29 16 56 -26 17 43 -171 0 0 -27 27 2 7 28 18 33 289 -14 -28 25 32 -26 29 31 -28 57 34 -25 58 51 -170 0 0 -27 8 22 7 28 20 32 289 -15 -28 6 42 -26 11 0 -28 38 39 -25 40 26 -169 0 0 -26 50 8 7 28 23 32 288 -16 -27 48 18 -25 52 56 -28 20 9 -25 22 26 -168 0 0 -26 32 20 7 28 26 31 287 -17 -27 30 21 -25 35 17 -28 2 7 -25 4 52 -167 0 0 -26 15 0 7 28 28 30 286 -18 -27 12 51 -25 18 6 -27 44 32 -24 47 45 -166 0 0 -25 58 6 7 28 31 29 286 -19 -26 55 49 -25 1 21 -27 27 24 -24 31 5 -165 0 0 -25 41 41 7 28 33 28 285 -20 -26 39 14 -24 45 4 -27 10 44 -24 14 52 -164 0 0 -25 25 43 7 28 35 28 284 -20 -26 23 8 -24 29 15 -26 54 33 -23 59 7 -163 0 0 -25 10 14 7 28 38 27 283 -21 -26 7 30 -24 13 53 -26 38 50 -23 43 50 -162 0 0 -24 55 13 7 28 40 26 283 -22 -25 52 20 -23 59 0 -26 23 36 -23 29 1 -161 0 0 -24 40 40 7 28 42 25 282 -23 -25 37 40 -23 44 36 -26 8 51 -23 14 41 -160 0 0 -24 26 37 7 28 44 24 282 -24 -25 23 29 -23 30 40 -25 54 36 -23 0 49 -159 0 0 -24 13 4 7 28 46 23 281 -25 -25 9 48 -23 17 14 -25 40 50 -22 47 27 -158 0 0 -23 59 59 7 28 48 22 280 -25 -24 56 36 -23 4 17 -25 27 34 -22 34 33 -157 0 0 -23 47 25 7 28 50 22 280 -26 -24 43 54 -22 51 49 -25 14 49 -22 22 9 -156 0 0 -23 35 20 7 28 51 21 279 -27 -24 31 43 -22 39 51 -25 2 33 -22 10 14 -155 0 0 -23 23 46 7 28 53 20 279 -28 -24 20 2 -22 28 23 -24 50 48 -21 58 49 -154 0 0 -23 12 41 7 28 55 19 278 -29 -24 8 51 -22 17 24 -24 39 34 -21 47 54 -153 0 0 -23 2 7 7 28 56 18 278 -29 -23 58 11 -22 6 56 -24 28 51 -21 37 29 -152 0 0 -22 52 4 7 28 58 17 277 -30 -23 48 2 -21 56 59 -24 18 38 -21 27 34 -151 0 0 -22 42 32 7 28 59 16 277 -31 -23 38 24 -21 47 31 -24 8 57 -21 18 10 -150 0 0 -22 33 30 7 29 1 15 276 -32 -23 29 17 -21 38 35 -23 59 47 -21 9 16 -149 0 0 -22 24 59 7 29 2 14 276 -32 -23 20 41 -21 30 9 -23 51 9 -21 0 52 -148 0 0 -22 16 59 7 29 3 14 276 -33 -23 12 37 -21 22 14 -23 43 1 -20 52 59 -147 0 0 -22 9 31 7 29 4 13 275 -34 -23 5 4 -21 14 49 -23 35 26 -20 45 37 -146 0 0 -22 2 33 7 29 5 12 275 -34 -22 58 2 -21 7 56 -23 28 22 -20 38 46 -145 0 0 -21 56 7 7 29 6 11 274 -35 -22 51 32 -21 1 33 -23 21 50 -20 32 26 -144 0 0 -21 50 12 7 29 7 10 274 -36 -22 45 34 -20 55 42 -23 15 49 -20 26 36 -143 0 0 -21 44 49 7 29 8 9 273 -36 -22 40 7 -20 50 22 -23 10 21 -20 21 17 -142 0 0 -21 39 57 7 29 9 8 273 -37 -22 35 12 -20 45 33 -23 5 24 -20 16 30 -141 0 0 -21 35 37 7 29 9 7 273 -37 -22 30 49 -20 41 15 -23 1 0 -20 12 13 -140 0 0 -21 31 48 7 29 10 6 272 -38 -22 26 58 -20 37 28 -22 57 7 -20 8 28 -139 0 0 -21 28 30 7 29 10 5 272 -38 -22 23 38 -20 34 13 -22 53 46 -20 5 14 -138 0 0 -21 25 45 7 29 11 4 272 -39 -22 20 50 -20 31 29 -22 50 57 -20 2 31 -137 0 0 -21 23 30 7 29 11 3 271 -39 -22 18 35 -20 29 16 -22 48 41 -20 0 19 -136 0 0 -21 21 48 7 29 11 2 271 -40 -22 16 51 -20 27 35 -22 46 56 -19 58 38 -135 0 0 -21 20 37 7 29 11 1 271 -40 -22 15 38 -20 26 25 -22 45 43 -19 57 28 -134 0 0 -21 19 57 7 29 12 1 270 -41 -22 14 58 -20 25 46 -22 45 3 .. .. .. Uncertainty in time = +/- 2 secs Prediction of 2012 Dec 3.0 Data for the target star ------------------------ * name: TYC 5233-01669-1 * constellation : Aquarius * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 22 31 59.5140 DE: -00 08 38.881 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .023, .023 ) * V mag [mag]: 11.2 * B mag [mag]: 11.7 * Diameter [mas]: 0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (141) Lumen approx. diameter [km]: 145 approx. diameter ["]: .091 distance from Earth [AU]: 2.20400 * orbital information: orbit source: Preston date of fit: 2012 Nov 16 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 804 number of rejected observations: 85 time covered by the observations: 1918 Jan 15 - 2012 Nov 12 1 sigma uncertainty ellipse (major, minor, PA): 0.016, 0.008, 54° remarks: * orbital elements for (141) Lumen : Mean anomaly = 353.57971059 deg Arg. of pericenter = 58.36502496 deg Long. of node = 318.54291925 deg Inclination = 11.88622486 deg Eccentricity = 0.21295196 Semimajor axis = 2.66589299 AU Perihelion dist = 2.09818584 AU Mag: H = 8.36, G = 0.15 Epoch of elements : MJD 56281.31000000 TDT (2012 Dec 20.310) ------ occelmnt file for Occult BEGIN ----------------------------------- 2012 Dec 20 141 Lumen 7h 26.6m UT 11.2 22 31 59.514- 0 8 38.88TYC 5233-01669-1 11.7 12.7 145 4.9 2.204 4.086 25.56 137.0604 -0.152 67.78 -23.43 7.4433 0.26759 -0.63857 15.35784 6.40610 0.00479 0.00222 2000 353.28308420121219.00000 58.365025318.542919 11.8862250.21295196 2.6658930 2.0981859 8.2 5.00.15 RATE 2.2643310 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.028 0.024 79 1.27 0.024 0 0 0-1 056264.0020121220_1669-1 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2012 Nov 16, 10:46 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org