IOTA/IOTA-ES occultation update for (174) Phaedra / TYC 7901-02054-1 event on 2007 Jul 02, 23:40 UT Visible from Africa Summary ------- On 2007 Jul 02 UT, the 69 km diameter asteroid (174) Phaedra will occult a 11.5 mag star in the constellation Corona Australis for observers along a path across Africa. In the case of an occultation, the combined light of the asteroid and the star will drop by 0.9 mag to 11.8 mag (the magnitude of the asteroid) for at most 7.2 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: 86 * date and approx. time of event: 2007 Jul 02, 23:34 - 2007 Jul 02, 23:45 UT * magnitude of target star: 11.5 * magnitude drop [mag]: 0.9 * estimated maximum duration [s]: 7.2 * Moon: 93 % sunlit, 38° distance * Sun: 163° distance * rough path description: Africa The occultation path -------------------- * approximate projected width [km]: 132 * 1 sigma uncertainty interval [path widths]: +/- 0.58 * 1 sigma uncertainty interval [seconds]: +/- 4.3 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .050 +/- .036) * 1 sigma uncertainty ellipse (major, minor, PA): ( .050", .036", 84° ) * approx speed of asteroid's shadow [km/s]: 9.6398 * website for maps: http://lunar-occultations.com/iota/asteroids/astrndx.htm http://www.asteroidoccultation.com Path Coordinates: Occultation of TYC 7901-02054-1 by 174 Phaedra on 2007 Jul 02 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 - 21 31 56 49 0 0 23 45 53 0 164 -14 - 20 33 8 ... .. .. - 19 23 43 ... .. .. - 21 4 55 48 0 0 23 45 53 1 164 -15 - 20 6 48 - 22 2 8 - 18 58 12 ... .. .. - 20 35 58 47 0 0 23 45 52 2 165 -17 - 19 38 27 - 21 32 35 - 18 30 34 ... .. .. - 20 5 6 46 0 0 23 45 51 3 165 -18 - 19 8 7 - 21 1 12 - 18 0 50 ... .. .. - 19 32 20 45 0 0 23 45 49 4 165 -19 - 18 35 48 - 20 27 59 - 17 29 2 ... .. .. - 18 57 41 44 0 0 23 45 48 5 166 -20 - 18 1 31 - 19 52 57 - 16 55 10 ... .. .. - 18 21 8 43 0 0 23 45 45 6 166 -21 - 17 25 15 - 19 16 7 - 16 19 14 ... .. .. - 17 42 40 42 0 0 23 45 42 8 167 -22 - 16 47 1 - 18 37 26 - 15 41 13 - 19 39 52 - 17 2 17 41 0 0 23 45 39 9 167 -23 - 16 6 45 - 17 56 53 - 15 1 6 - 18 59 8 - 16 19 55 40 0 0 23 45 35 10 168 -24 - 15 24 27 - 17 14 26 - 14 18 50 - 18 16 35 - 15 35 31 39 0 0 23 45 30 11 168 -25 - 14 40 2 - 16 30 3 - 13 34 21 - 17 32 10 - 14 49 3 38 0 0 23 45 25 12 169 -26 - 13 53 27 - 15 43 40 - 12 47 36 - 16 45 51 - 14 0 26 37 0 0 23 45 20 13 169 -28 - 13 4 37 - 14 55 12 - 11 58 30 - 15 57 32 - 13 9 33 36 0 0 23 45 14 14 170 -29 - 12 13 27 - 14 4 35 - 11 6 55 - 15 7 11 - 12 16 19 35 0 0 23 45 7 15 170 -30 - 11 19 49 - 13 11 43 - 10 12 46 - 14 14 40 - 11 20 37 34 0 0 23 44 59 16 171 -31 - 10 23 36 - 12 16 28 - 9 15 52 - 13 19 54 - 10 22 17 33 0 0 23 44 51 17 172 -32 - 9 24 37 - 11 18 42 - 8 16 2 - 12 22 44 - 9 21 8 32 0 0 23 44 43 18 173 -33 - 8 22 41 - 10 18 16 - 7 13 5 - 11 23 2 - 8 16 58 31 0 0 23 44 33 20 173 -35 - 7 17 35 - 9 14 58 - 6 6 45 - 10 20 37 - 7 9 32 30 0 0 23 44 23 21 174 -36 - 6 9 1 - 8 8 33 - 4 56 42 - 9 15 16 - 5 58 32 29 0 0 23 44 11 22 175 -37 - 4 56 39 - 6 58 46 - 3 42 35 - 8 6 46 - 4 43 36 28 0 0 23 43 59 23 176 -38 - 3 40 6 - 5 45 17 - 2 23 54 - 6 54 47 - 3 24 17 27 0 0 23 43 46 24 177 -39 - 2 18 50 - 4 27 42 - 1 0 5 - 5 39 0 - 2 0 0 26 0 0 23 43 32 25 178 -41 - 0 52 13 - 3 5 31 0 29 39 - 4 18 57 - 0 30 4 25 0 0 23 43 16 26 179 -42 0 40 35 - 1 38 6 2 6 17 - 2 54 7 1 6 27 24 0 0 23 42 59 27 181 -43 2 20 38 - 0 4 40 3 51 11 - 1 23 48 2 50 48 23 0 0 23 42 41 28 182 -44 4 9 29 1 35 50 5 46 16 0 12 50 4 44 44 22 0 0 23 42 20 29 184 -45 6 9 16 3 24 49 7 54 24 1 57 0 6 50 47 21 0 0 23 41 57 30 186 -46 8 23 17 5 24 21 10 20 19 3 50 15 Latitude Latitude Latitude Latitude 7 0 0 20 55 52 23 41 55 30 186 -46 21 36 25 20 16 10 22 24 37 19 31 8 8 0 0 20 29 48 23 41 44 30 187 -47 21 9 54 19 50 32 21 57 32 19 5 56 9 0 0 20 5 9 23 41 33 30 188 -47 20 44 50 19 26 16 21 31 57 18 42 7 10 0 0 19 41 54 23 41 22 31 188 -47 20 21 12 19 3 23 21 7 50 18 19 37 11 0 0 19 20 1 23 41 11 31 189 -47 19 58 58 18 41 50 20 45 9 17 58 26 12 0 0 18 59 29 23 41 1 31 190 -48 19 38 6 18 21 37 20 23 54 17 38 33 13 0 0 18 40 17 23 40 50 31 191 -48 19 18 36 18 2 42 20 4 1 17 19 56 14 0 0 18 22 24 23 40 39 31 192 -48 19 0 26 17 45 4 19 45 30 17 2 36 15 0 0 18 5 48 23 40 28 31 193 -48 18 43 35 17 28 43 19 28 21 16 46 30 16 0 0 17 50 29 23 40 17 31 194 -48 18 28 3 17 13 37 19 12 32 16 31 39 17 0 0 17 36 27 23 40 6 31 195 -48 18 13 48 16 59 46 18 58 1 16 18 1 18 0 0 17 23 39 23 39 55 31 195 -48 18 0 49 16 47 9 18 44 49 16 5 36 19 0 0 17 12 7 23 39 44 31 196 -48 17 49 7 16 35 46 18 32 54 15 54 23 20 0 0 17 1 48 23 39 34 31 197 -48 17 38 40 16 25 36 18 22 16 15 44 22 21 0 0 16 52 44 23 39 23 31 198 -48 17 29 27 16 16 39 18 12 54 15 35 32 22 0 0 16 44 52 23 39 13 31 199 -47 17 21 29 16 8 53 18 4 49 15 27 54 23 0 0 16 38 14 23 39 2 31 200 -47 17 14 45 16 2 20 17 57 58 15 21 26 24 0 0 16 32 48 23 38 52 30 200 -47 17 9 15 15 56 58 17 52 23 15 16 8 25 0 0 16 28 34 23 38 41 30 201 -47 17 4 59 15 52 47 17 48 2 15 12 1 26 0 0 16 25 33 23 38 31 30 202 -46 17 1 56 15 49 48 17 44 57 15 9 4 27 0 0 16 23 44 23 38 21 30 203 -46 17 0 6 15 48 0 17 43 6 15 7 17 28 0 0 16 23 8 23 38 11 29 203 -45 16 59 29 15 47 23 17 42 29 15 6 40 29 0 0 16 23 43 23 38 1 29 204 -45 17 0 6 15 47 58 17 43 8 15 7 13 30 0 0 16 25 31 23 37 51 28 205 -44 17 1 56 15 49 44 17 45 1 15 8 57 31 0 0 16 28 32 23 37 42 28 206 -44 17 5 0 15 52 42 17 48 9 15 11 51 32 0 0 16 32 46 23 37 32 28 206 -43 17 9 19 15 56 51 17 52 32 15 15 56 33 0 0 16 38 13 23 37 23 27 207 -43 17 14 51 16 2 13 17 58 12 15 21 12 34 0 0 16 44 54 23 37 13 27 208 -42 17 21 39 16 8 47 18 5 7 15 27 40 35 0 0 16 52 49 23 37 4 26 208 -42 17 29 41 16 16 35 18 13 20 15 35 19 36 0 0 17 1 58 23 36 55 25 209 -41 17 39 0 16 25 36 18 22 50 15 44 11 37 0 0 17 12 23 23 36 47 25 210 -40 17 49 35 16 35 51 18 33 38 15 54 15 38 0 0 17 24 5 23 36 38 24 210 -39 18 1 28 16 47 22 18 45 44 16 5 34 39 0 0 17 37 3 23 36 29 24 211 -39 18 14 39 17 0 8 18 59 11 16 18 6 40 0 0 17 51 18 23 36 21 23 211 -38 18 29 9 17 14 10 19 13 59 16 31 54 41 0 0 18 6 53 23 36 13 22 212 -37 18 44 59 17 29 30 19 30 8 16 46 58 42 0 0 18 23 48 23 36 5 21 212 -36 19 2 11 17 46 8 19 47 41 17 3 19 43 0 0 18 42 3 23 35 57 21 213 -36 19 20 45 18 4 6 20 6 39 17 20 57 44 0 0 19 1 41 23 35 50 20 213 -35 19 40 43 18 23 25 20 27 2 17 39 55 45 0 0 19 22 43 23 35 43 19 214 -34 20 2 7 18 44 6 20 48 53 18 0 14 46 0 0 19 45 10 23 35 36 18 215 -33 20 24 58 19 6 10 21 12 14 18 21 54 47 0 0 20 9 4 23 35 29 17 215 -32 20 49 18 19 29 40 21 37 6 18 44 57 48 0 0 20 34 26 23 35 22 17 216 -31 21 15 8 19 54 36 22 3 31 19 9 25 49 0 0 21 1 20 23 35 16 16 216 -30 21 42 32 20 21 1 22 31 33 19 35 19 50 0 0 21 29 46 23 35 10 15 216 -29 22 11 31 20 48 57 23 1 13 20 2 42 51 0 0 21 59 47 23 35 5 14 217 -28 22 42 8 21 18 26 23 32 34 20 31 34 52 0 0 22 31 27 23 34 59 13 217 -27 23 14 25 21 49 29 24 5 39 21 2 0 53 0 0 23 4 46 23 34 54 12 218 -26 23 48 26 22 22 10 24 40 32 21 34 0 54 0 0 23 39 49 23 34 50 11 218 -25 24 24 13 22 56 32 25 17 16 22 7 37 55 0 0 24 16 39 23 34 45 10 219 -24 25 1 52 23 32 37 25 55 56 22 42 54 56 0 0 24 55 19 23 34 42 9 219 -23 25 41 25 24 10 29 26 36 36 23 19 54 57 0 0 25 35 54 23 34 38 8 220 -22 26 22 56 24 50 11 27 19 21 23 58 40 58 0 0 26 18 28 23 34 35 7 220 -21 27 6 32 25 31 47 28 4 16 24 39 15 59 0 0 27 3 5 23 34 32 5 221 -19 27 52 18 26 15 22 28 51 30 25 21 45 60 0 0 27 49 51 23 34 30 4 221 -18 28 40 19 27 1 1 29 41 8 .. .. .. 61 0 0 28 38 53 23 34 29 3 222 -17 29 30 43 27 48 49 30 33 19 .. .. .. 62 0 0 29 30 18 23 34 28 2 222 -16 30 23 39 .. .. .. 31 28 14 .. .. .. 63 0 0 30 24 13 23 34 27 1 223 -15 .. .. .. .. .. .. .. .. .. .. .. .. Data for the target star ------------------------ * name: TYC 7901-02054-1 * constellation : Corona Australis * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 18 25 42.8853 DE: -39 10 48.402 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .031, .030 ) * V mag [mag]: 11.5 * B mag [mag]: 13.2 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (174) Phaedra approx. diameter [km]: 69 approx. diameter ["]: .065 distance from Earth [AU]: 1.46900 * orbital information: orbit source: Preston date of fit: 2007 Jun 28 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 669 number of rejected observations: 96 time covered by the observations: 1901 Aug 14 - 2007 Jun 05 1 sigma uncertainty ellipse (major, minor, PA): 0.040, 0.019, 80° remarks: * orbital elements for (174) Phaedra : Mean anomaly = 14.41634386 deg Arg. of pericenter = 289.60415315 deg Long. of node = 327.75481844 deg Inclination = 12.12798874 deg Eccentricity = 0.14597003 Semimajor axis = 2.85972257 AU Perihelion dist = 2.44228879 AU Mag: H = 8.29, G = 0.15 Epoch of elements : MJD 54283.98700000 TDT (2007 Jul 02.987) ------ occelmnt file for Occult BEGIN ----------------------------------- 2007 Jul 02 174 Phaedra 23h 40.2m UT 11.5 18 25 42.885-39 10 48.40TYC 7901-02054-1 13.2 11.8 69 7.2 1.469 -2.670 9.84 0.757 -39.181 -174.02 23.01 23.6696 .25751 .81383 -5.18734 1.64185 0.00042 0.00149 2000 13.60376712007 629.00000289.604153327.754818 12.1279890.145970032.859722572.442288798.485 0.15 RATE 2.0380659 .0000000 .0000000 .0000000 .00000000 .00000000 .00000000 Meas 0.050 0.036 83.7 1.580 0.038 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2007 Jun 29, 02:05 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org