IOTA/IOTA-ES occultation update for (1609) Brenda / UCAC2 25579262 event on 2009 Jul 09, 04:08 UT Visible from Summary ------- On 2009 Jul 09 UT, the 30 km diameter asteroid (1609) Brenda will occult a 11.3 mag star in the constellation Ophiuchus for observers along a path across . In the case of an occultation, the combined light of the asteroid and the star will drop by 2.2 mag to 13.3 mag (the magnitude of the asteroid) for at most 2.8 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: 26 * date and approx. time of event: 2009 Jul 09, 04:00 - 2009 Jul 09, 04:13 UT * magnitude of target star: 11.3 * magnitude drop [mag]: 2.2 * estimated maximum duration [s]: 2.8 * Moon: 97 % sunlit, 43° distance * Sun: 156° distance * rough path description: The occultation path -------------------- * approximate projected width [km]: 41 * 1 sigma uncertainty interval [path widths]: +/- 2.58 * 1 sigma uncertainty interval [seconds]: +/- 7.1 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .094 +/- .086) * 1 sigma uncertainty ellipse (major, minor, PA): ( .094", .086", 95° ) * approx speed of asteroid's shadow [km/s]: 10.5794 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of UCAC2 25579262 by 1609 Brenda on 2009 Jul 9 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 - 72 46 19 67 0 0 4 0 6 6 190 0 - 73 16 12 - 72 16 27 - 75 51 1 - 69 42 49 - 73 30 21 66 0 0 4 0 7 7 190 -1 - 73 59 8 - 73 1 37 - 76 28 13 - 70 33 44 - 74 13 41 65 0 0 4 0 9 8 189 -2 - 74 41 26 - 73 45 57 - 77 5 17 - 71 23 20 - 74 56 24 64 0 0 4 0 11 9 188 -3 - 75 23 14 - 74 29 36 - 77 42 16 - 72 11 49 - 75 38 38 63 0 0 4 0 14 10 188 -4 - 76 4 36 - 75 12 41 - 78 19 13 - 72 59 19 - 76 20 27 62 0 0 4 0 17 11 187 -5 - 76 45 38 - 75 55 18 - 78 56 11 - 73 46 0 - 77 1 57 61 0 0 4 0 20 12 186 -6 - 77 26 24 - 76 37 31 - 79 33 12 - 74 31 59 - 77 43 12 60 0 0 4 0 23 13 186 -6 - 78 6 59 - 77 19 27 - 80 10 19 - 75 17 23 - 78 24 15 59 0 0 4 0 27 14 185 -7 - 78 47 25 - 78 1 7 - 80 47 32 - 76 2 17 - 79 5 11 58 0 0 4 0 31 15 185 -8 - 79 27 46 - 78 42 38 - 81 24 54 - 76 46 46 - 79 46 1 57 0 0 4 0 35 16 184 -9 - 80 8 4 - 79 24 0 - 82 2 26 - 77 30 55 - 80 26 50 56 0 0 4 0 39 17 183 -10 - 80 48 23 - 80 5 19 - 82 40 10 - 78 14 49 - 81 7 39 55 0 0 4 0 44 18 183 -10 - 81 28 45 - 80 46 36 - 83 18 8 - 78 58 30 - 81 48 32 54 0 0 4 0 49 19 182 -11 - 82 9 11 - 81 27 55 - 83 56 21 - 79 42 3 - 82 29 30 53 0 0 4 0 54 20 181 -12 - 82 49 45 - 82 9 17 - 84 34 50 - 80 25 30 - 83 10 35 52 0 0 4 1 0 21 181 -13 - 83 30 28 - 82 50 45 - 85 13 36 - 81 8 54 - 83 51 51 51 0 0 4 1 6 22 180 -14 - 84 11 22 - 83 32 21 - 85 52 42 - 81 52 19 - 84 33 17 50 0 0 4 1 12 23 179 -14 - 84 52 29 - 84 14 7 - 86 32 9 - 82 35 46 - 85 14 57 49 0 0 4 1 18 24 178 -15 - 85 33 51 - 84 56 6 - 87 11 57 - 83 19 19 - 85 56 53 48 0 0 4 1 25 25 178 -16 - 86 15 30 - 85 38 18 - 87 52 8 - 84 2 59 - 86 39 5 47 0 0 4 1 32 26 177 -16 - 86 57 26 - 86 20 47 - 88 32 43 - 84 46 49 - 87 21 37 46 0 0 4 1 39 27 176 -17 - 87 39 43 - 87 3 33 - 89 13 45 - 85 30 51 - 88 4 29 45 0 0 4 1 46 28 175 -18 - 88 22 22 - 87 46 38 - 89 55 14 - 86 15 7 - 88 47 43 44 0 0 4 1 54 29 175 -18 - 89 5 24 - 88 30 5 - 90 37 11 - 86 59 39 - 89 31 22 43 0 0 4 2 2 30 174 -19 - 89 48 51 - 89 13 56 - 91 19 39 - 87 44 30 - 90 15 27 42 0 0 4 2 10 31 173 -20 - 90 32 45 - 89 58 11 - 92 2 39 - 88 29 40 - 90 59 59 41 0 0 4 2 19 32 172 -20 - 91 17 7 - 90 42 53 - 92 46 11 - 89 15 13 - 91 45 1 40 0 0 4 2 28 33 171 -21 - 92 2 0 - 91 28 4 - 93 30 19 - 90 1 10 - 92 30 34 39 0 0 4 2 37 34 170 -21 - 92 47 26 - 92 13 45 - 94 15 4 - 90 47 34 - 93 16 41 38 0 0 4 2 46 35 169 -22 - 93 33 25 - 92 59 59 - 95 0 27 - 91 34 26 - 94 3 23 37 0 0 4 2 56 36 168 -22 - 94 20 1 - 93 46 47 - 95 46 30 - 92 21 48 - 94 50 42 36 0 0 4 3 6 37 167 -23 - 95 7 15 - 94 34 12 - 96 33 16 - 93 9 43 - 95 38 41 35 0 0 4 3 16 37 166 -23 - 95 55 9 - 95 22 16 - 97 20 47 - 93 58 12 - 96 27 22 34 0 0 4 3 26 38 165 -24 - 96 43 46 - 96 11 1 - 98 9 4 - 94 47 19 - 97 16 48 33 0 0 4 3 37 39 164 -24 - 97 33 8 - 97 0 30 - 98 58 11 - 95 37 6 - 98 7 0 32 0 0 4 3 48 40 163 -24 - 98 23 18 - 97 50 45 - 99 48 9 - 96 27 34 - 98 58 1 31 0 0 4 3 59 40 162 -25 - 99 14 18 - 98 41 48 -100 39 2 - 97 18 48 - 99 49 55 30 0 0 4 4 11 41 160 -25 -100 6 11 - 99 33 43 -101 30 52 - 98 10 48 -100 42 45 29 0 0 4 4 23 42 159 -25 -100 59 0 -100 26 32 -102 23 43 - 99 3 40 -101 36 33 28 0 0 4 4 35 43 158 -26 -101 52 49 -101 20 19 -103 17 37 - 99 57 24 -102 31 22 27 0 0 4 4 47 43 156 -26 -102 47 41 -102 15 8 -104 12 40 -100 52 6 -103 27 18 26 0 0 4 5 0 44 155 -26 -103 43 39 -103 11 1 -105 8 54 -101 47 48 -104 24 24 25 0 0 4 5 12 44 153 -26 -104 40 48 -104 8 3 -106 6 24 -102 44 34 -105 22 44 24 0 0 4 5 26 45 152 -26 -105 39 13 -105 6 18 -107 5 15 -103 42 29 -106 22 23 23 0 0 4 5 39 45 150 -26 -106 38 57 -106 5 52 -108 5 31 -104 41 36 -107 23 26 22 0 0 4 5 53 46 148 -26 -107 40 8 -107 6 49 -109 7 20 -105 42 1 -108 26 0 21 0 0 4 6 7 46 147 -26 -108 42 49 -108 9 14 -110 10 46 -106 43 49 -109 30 10 20 0 0 4 6 21 46 145 -26 -109 47 9 -109 13 15 -111 15 58 -107 47 6 -110 36 4 19 0 0 4 6 36 47 143 -26 -110 53 14 -110 18 59 -112 23 4 -108 51 59 -111 43 49 18 0 0 4 6 50 47 141 -26 -112 1 12 -111 26 32 -113 32 11 -109 58 33 -112 53 35 17 0 0 4 7 6 47 140 -25 -113 11 12 -112 36 4 -114 43 31 -111 6 58 -114 5 32 16 0 0 4 7 21 47 138 -25 -114 23 25 -113 47 45 -115 57 14 -112 17 23 -115 19 51 15 0 0 4 7 37 47 136 -25 -115 38 3 -115 1 46 -117 13 35 -113 29 56 -116 36 46 14 0 0 4 7 53 47 134 -24 -116 55 19 -116 18 20 -118 32 49 -114 44 51 -117 56 31 13 0 0 4 8 10 46 132 -24 -118 15 28 -117 37 42 -119 55 14 -116 2 19 -119 19 25 12 0 0 4 8 27 46 130 -23 -119 38 50 -119 0 8 -121 21 11 -117 22 37 -120 45 49 11 0 0 4 8 44 46 128 -23 -121 5 46 -120 26 1 -122 51 7 -118 46 1 -122 16 8 10 0 0 4 9 2 45 126 -22 -122 36 42 -121 55 44 -124 25 32 -120 12 53 -123 50 53 9 0 0 4 9 20 45 124 -21 -124 12 10 -123 29 47 -126 5 6 -121 43 38 -125 30 42 8 0 0 4 9 38 44 122 -20 -125 52 50 -125 8 47 -127 50 38 -123 18 46 -127 16 23 7 0 0 4 9 58 43 120 -19 -127 39 32 -126 53 29 -129 43 13 -124 58 54 -129 8 59 6 0 0 4 10 17 42 119 -18 -129 33 21 -128 44 53 -131 44 17 -126 44 50 -131 9 52 5 0 0 4 10 38 41 117 -17 -131 35 47 -130 44 19 -133 55 52 -128 37 34 Latitude Latitude Latitude Latitude -133 0 0 4 9 15 4 10 56 39 115 -15 4 21 24 3 57 9 5 24 49 2 55 20 -134 0 0 3 43 9 4 11 5 39 115 -15 3 55 13 3 31 8 4 58 12 2 29 43 -135 0 0 3 18 8 4 11 15 38 114 -14 3 30 7 3 6 11 4 32 41 2 5 9 -136 0 0 2 54 11 4 11 24 37 113 -13 3 6 6 2 42 18 4 8 16 1 41 38 -137 0 0 2 31 17 4 11 33 37 113 -12 2 43 8 2 19 29 3 44 56 1 19 10 -138 0 0 2 9 27 4 11 42 36 112 -12 2 21 14 1 57 42 3 22 41 0 57 43 -139 0 0 1 48 39 4 11 50 35 112 -11 2 0 22 1 36 58 3 1 29 0 37 17 -140 0 0 1 28 53 4 11 59 34 111 -10 1 40 33 1 17 16 2 41 21 0 17 52 -141 0 0 1 10 9 4 12 7 33 111 -9 1 21 46 0 58 35 2 22 16 - 0 0 32 -142 0 0 0 52 26 4 12 15 33 110 -9 1 4 0 0 40 55 2 4 14 - 0 17 56 -143 0 0 0 35 45 4 12 22 32 110 -8 0 47 15 0 24 16 1 47 14 - 0 34 21 -144 0 0 0 20 3 4 12 30 31 110 -7 0 31 31 0 8 38 1 31 16 - 0 49 46 -145 0 0 0 5 22 4 12 37 30 109 -6 0 16 48 - 0 6 1 1 16 19 - 1 4 12 -146 0 0 - 0 8 19 4 12 44 29 109 -5 0 3 4 - 0 19 40 1 2 24 - 1 17 40 -147 0 0 - 0 21 0 4 12 51 28 109 -5 - 0 9 39 - 0 32 19 0 49 29 - 1 30 8 -148 0 0 - 0 32 42 4 12 58 28 109 -4 - 0 21 23 - 0 43 59 0 37 35 - 1 41 39 -149 0 0 - 0 43 25 4 13 5 27 108 -3 - 0 32 8 - 0 54 40 0 26 41 - 1 52 12 -150 0 0 - 0 53 9 4 13 11 26 108 -2 - 0 41 53 - 1 4 23 0 16 47 - 2 1 47 -151 0 0 - 1 1 54 4 13 17 25 108 -1 - 0 50 40 - 1 13 6 0 7 54 - 2 10 24 -152 0 0 - 1 9 41 4 13 23 24 108 0 - 0 58 27 - 1 20 52 - 0 0 0 - 2 18 3 Uncertainty in time = +/- 8 secs [Prediction of 2008 Mar 20.0] Data for the target star ------------------------ * name: UCAC2 25579262 * constellation : Ophiuchus * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 17 34 21.2719 DE: -16 38 00.930 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .081, .081 ) * V mag [mag]: 11.3 * B mag [mag]: 0.0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (1609) Brenda approx. diameter [km]: 30 approx. diameter ["]: .035 distance from Earth [AU]: 1.18300 * orbital information: orbit source: Preston date of fit: 2008 Mar 20 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 778 number of rejected observations: 39 time covered by the observations: 1934 Jun 05 - 2008 Feb 08 1 sigma uncertainty ellipse (major, minor, PA): 0.048, 0.029, 109° remarks: * orbital elements for (1609) Brenda : Mean anomaly = 322.44752187 deg Arg. of pericenter = 228.62775450 deg Long. of node = 105.46325569 deg Inclination = 18.66644015 deg Eccentricity = 0.25070527 Semimajor axis = 2.58226260 AU Perihelion dist = 1.93487576 AU Mag: H = 10.54, G = 0.15 Epoch of elements : MJD 55021.17200000 TDT (2009 Jul 09.172) ------ occelmnt file for Occult BEGIN ----------------------------------- 2009 Jul 9 1609 Brenda 4h 7.3m UT 11.3 17 34 21.272-16 38 0.93UCAC2 25579262 0.0 13.3 30 2.8 1.183 -2.289 -29.81 -85.4758 -16.624 119.48 22.34 4.1218 -0.45927 0.50673 -4.42609 -4.00831 0.00200 -0.00064 2000 322.1691462009 7 8.00000228.627755105.463256 18.6664400.25070527 2.5822626 1.934875810.6 5.00.15 RATE 2.3752180 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.094 0.086 95 3.58 0.090 0 54545.5020090709_579262 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2008 Mar 20, 10:32 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org