IOTA/IOTA-ES occultation update for (1070) Tunica / UCAC2 29331807 event on 2012 Sep 05, 06:02 UT Visible from S Pacific Ocean Summary ------- On 2012 Sep 05 UT, the 39 km diameter asteroid (1070) Tunica will occult a 11.9 mag star in the constellation Scutum 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 4.1 mag to 16.0 mag (the magnitude of the asteroid) for at most 4.2 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: 17 * date and approx. time of event: 2012 Sep 05, 05:56 - 2012 Sep 05, 06:12 UT * geocentric midpoint of event [JD]: 2456175.7515125 * magnitude of target star: 11.9 * magnitude drop [mag]: 4.1 * estimated maximum duration [s]: 4.2 * Moon: 79 % sunlit, 112° distance * Sun: 119° distance * rough path description: S Pacific Ocean The occultation path -------------------- * approximate projected width [km]: 41 * 1 sigma uncertainty interval [path widths]: +/- 3.89 * 1 sigma uncertainty interval [seconds]: +/- 15.6 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- .086 +/- .081) * 1 sigma uncertainty ellipse (major, minor, PA): ( .086", .081", 91° ) * approx speed of asteroid's shadow [km/s]: 9.2222 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of UCAC2 29331807 by 1070 Tunica on 2012 Sep 5 Centre Star Star Sun Path Limit1 Path Limit2 Error Limit1 Error Limit2 E. Longitude Latitude U.T. Alt Az Alt o ' " o ' " h m s o o o o ' " o ' " o ' " o ' " o ' " o ' " o ' " o ' " Longitude Latitude Longitude Latitude Longitude Latitude Longitude Latitude -177 12 27 13 42 40 5 56 57 57 128 -1 -177 1 14 13 45 13 -177 23 42 13 40 7 -175 34 22 14 5 17 -178 51 44 13 20 32 -176 40 31 12 16 26 5 57 14 58 127 -1 -176 29 23 12 18 59 -176 51 41 12 13 54 -175 3 9 12 38 59 -178 19 3 11 54 21 -176 10 14 10 51 3 5 57 30 59 125 -2 -175 59 10 10 53 35 -176 21 19 10 48 31 -174 33 30 11 13 33 -177 48 7 10 29 0 -175 41 27 9 26 25 5 57 47 61 124 -3 -175 30 27 9 28 57 -175 52 29 9 23 54 -174 5 16 9 48 52 -177 18 46 9 4 25 -175 14 3 8 2 29 5 58 3 62 122 -4 -175 3 6 8 5 1 -175 25 1 7 59 58 -173 38 20 8 24 54 -176 50 52 7 40 31 -174 47 54 6 39 11 5 58 20 63 121 -4 -174 37 0 6 41 43 -174 58 50 6 36 40 -173 12 36 7 1 34 -176 24 18 6 17 13 -174 22 55 5 16 26 5 58 36 64 119 -5 -174 12 3 5 18 58 -174 33 48 5 13 55 -172 47 57 5 38 48 -175 58 59 4 54 29 -173 59 1 3 54 11 5 58 53 65 117 -6 -173 48 10 3 56 42 -174 9 52 3 51 40 -172 24 18 4 16 32 -175 34 47 3 32 14 -173 36 5 2 32 22 5 59 9 66 115 -6 -173 25 16 2 34 54 -173 46 55 2 29 51 -172 1 35 2 54 44 -175 11 39 2 10 25 -173 14 5 1 10 57 5 59 26 67 112 -7 -173 3 17 1 13 29 -173 24 53 1 8 26 -171 39 43 1 33 19 -174 49 30 0 48 59 -172 52 55 - 0 10 8 5 59 42 68 110 -7 -172 42 8 - 0 7 36 -173 3 43 - 0 12 40 -171 18 39 0 12 15 -174 28 15 - 0 32 8 -172 32 33 - 1 30 56 5 59 59 69 107 -8 -172 21 46 - 1 28 24 -172 43 21 - 1 33 28 -170 58 19 - 1 8 31 -174 7 51 - 1 52 58 -172 12 55 - 2 51 30 6 0 15 69 104 -8 -172 2 8 - 2 48 58 -172 23 44 - 2 54 2 -170 38 40 - 2 29 3 -173 48 15 - 3 13 34 -171 53 59 - 4 11 52 6 0 32 70 100 -9 -171 43 11 - 4 9 20 -172 4 48 - 4 14 25 -170 19 38 - 3 49 23 -173 29 24 - 4 34 0 -171 35 41 - 5 32 6 6 0 48 71 97 -9 -171 24 52 - 5 29 33 -171 46 31 - 5 34 39 -170 1 12 - 5 9 33 -173 11 15 - 5 54 17 -171 17 59 - 6 52 14 6 1 5 71 93 -10 -171 7 9 - 6 49 40 -171 28 50 - 6 54 47 -169 43 19 - 6 29 37 -172 53 45 - 7 14 29 -171 0 52 - 8 12 18 6 1 21 71 89 -10 -170 50 0 - 8 9 44 -171 11 44 - 8 14 52 -169 25 56 - 7 49 37 -172 36 53 - 8 34 38 -170 44 16 - 9 32 22 6 1 38 72 85 -11 -170 33 22 - 9 29 48 -170 55 10 - 9 34 57 -169 9 2 - 9 9 36 -172 20 36 - 9 54 47 -170 28 9 -10 52 28 6 1 54 72 81 -11 -170 17 13 -10 49 53 -170 39 7 -10 55 3 -168 52 35 -10 29 36 -172 4 53 -11 14 59 -170 12 31 -12 12 39 6 2 11 72 77 -12 -170 1 32 -12 10 3 -170 23 32 -12 15 15 -168 36 31 -11 49 40 -171 49 41 -12 35 17 -169 57 20 -13 32 57 6 2 27 72 72 -12 -169 46 17 -13 30 20 -170 8 23 -13 35 33 -168 20 51 -13 9 51 -171 35 0 -13 55 42 -169 42 33 -14 53 25 6 2 44 72 68 -13 -169 31 27 -14 50 47 -169 53 41 -14 56 2 -168 5 32 -14 30 12 -171 20 47 -15 16 18 -169 28 10 -16 14 6 6 3 0 71 64 -13 -169 16 59 -16 11 27 -169 39 22 -16 16 44 -167 50 33 -15 50 44 -171 7 2 -16 37 7 -169 14 9 -17 35 3 6 3 17 71 60 -13 -169 2 54 -17 32 23 -169 25 26 -17 37 42 -167 35 52 -17 11 31 -170 53 43 -17 58 13 -169 0 30 -18 56 18 6 3 33 71 56 -14 -168 49 9 -18 53 37 -169 11 51 -18 58 58 -167 21 28 -18 32 36 -170 40 50 -19 19 38 -168 47 10 -20 17 54 6 3 50 70 53 -14 -168 35 44 -20 15 12 -168 58 37 -20 20 36 -167 7 20 -19 54 2 -170 28 21 -20 41 26 -168 34 9 -21 39 56 6 4 6 69 49 -14 -168 22 37 -21 37 12 -168 45 42 -21 42 39 -166 53 25 -21 15 52 -170 16 16 -22 3 39 -168 21 26 -23 2 25 6 4 23 69 46 -15 -168 9 47 -22 59 40 -168 33 6 -23 5 9 -166 39 44 -22 38 8 -170 4 35 -23 26 21 -168 9 0 -24 25 25 6 4 39 68 43 -15 -167 57 14 -24 22 39 -168 20 48 -24 28 12 -166 26 15 -24 0 55 -169 53 16 -24 49 35 -167 56 51 -25 49 1 6 4 56 67 40 -15 -167 44 56 -25 46 13 -168 8 47 -25 51 49 -166 12 56 -25 24 16 -169 42 19 -26 13 25 -167 44 57 -27 13 15 6 5 12 66 38 -15 -167 32 54 -27 10 25 -167 57 2 -27 16 5 -165 59 47 -26 48 14 -169 31 45 -27 37 55 -167 33 18 -28 38 12 6 5 29 65 35 -16 -167 21 5 -28 35 20 -167 45 32 -28 41 4 -165 46 46 -28 12 54 -169 21 32 -29 3 9 -167 21 53 -30 3 57 6 5 45 64 33 -16 -167 9 30 -30 1 3 -167 34 18 -30 6 50 -165 33 53 -29 38 20 -169 11 41 -30 29 12 -167 10 43 -31 30 33 6 6 2 63 31 -16 -166 58 8 -31 27 36 -167 23 19 -31 33 29 -165 21 5 -31 4 36 -169 2 13 -31 56 8 -166 59 46 -32 58 6 6 6 18 62 29 -16 -166 46 59 -32 55 7 -167 12 34 -33 1 4 -165 8 22 -32 31 47 -168 53 7 -33 24 2 -166 49 2 -34 26 41 6 6 35 60 27 -16 -166 36 1 -34 23 40 -167 2 4 -34 29 42 -164 55 44 -34 0 0 -168 44 25 -34 53 1 -166 38 31 -35 56 25 6 6 51 59 26 -16 -166 25 16 -35 53 21 -166 51 47 -35 59 29 -164 43 7 -35 29 18 -168 36 7 -36 23 10 -166 28 13 -37 27 24 6 7 8 58 24 -16 -166 14 42 -37 24 17 -166 41 46 -37 30 31 -164 30 32 -36 59 50 -168 28 15 -37 54 36 -166 18 8 -38 59 45 6 7 24 57 23 -17 -166 4 19 -38 56 35 -166 31 59 -39 2 56 -164 17 57 -38 31 41 -168 20 50 -39 27 27 -166 8 17 -40 33 37 6 7 41 55 22 -17 -165 54 9 -40 30 23 -166 22 27 -40 36 51 -164 5 21 -40 5 1 -168 13 55 -41 1 50 -165 58 40 -42 9 9 6 7 57 54 21 -17 -165 44 10 -42 5 50 -166 13 11 -42 12 27 -163 52 42 -41 39 57 -168 7 33 -42 37 57 -165 49 18 -43 46 30 6 8 14 52 19 -17 -165 34 25 -43 43 7 -166 4 13 -43 49 52 -163 39 58 -43 16 39 -168 1 48 -44 15 56 -165 40 12 -45 25 53 6 8 30 51 18 -16 -165 24 53 -45 22 25 -165 55 34 -45 29 20 -163 27 8 -44 55 20 -167 56 44 -45 56 1 -165 31 25 -47 7 31 6 8 47 49 17 -16 -165 15 36 -47 3 58 -165 47 17 -47 11 4 -163 14 10 -46 36 10 -167 52 28 -47 38 26 -165 23 0 -48 51 39 6 9 3 48 17 -16 -165 6 37 -48 48 1 -165 39 25 -48 55 18 -163 1 3 -48 19 27 -167 49 9 -49 23 26 -165 14 59 -50 38 37 6 9 20 46 16 -16 -164 57 59 -50 34 51 -165 32 3 -50 42 22 -162 47 42 -50 5 25 -167 46 58 -51 11 21 -165 7 29 -52 28 44 6 9 36 44 15 -16 -164 49 45 -52 24 51 -165 25 16 -52 32 36 -162 34 7 -51 54 27 -167 46 9 -53 2 33 -165 0 37 -54 22 27 6 9 53 42 14 -16 -164 42 3 -54 18 26 -165 19 15 -54 26 28 -162 20 13 -53 46 56 -167 47 4 -54 57 29 -164 54 34 -56 20 18 6 10 9 40 14 -15 -164 35 1 -56 16 7 -165 14 12 -56 24 28 -162 5 58 -55 43 22 -167 50 11 -56 56 43 -164 49 36 -58 22 54 6 10 26 38 13 -15 -164 28 53 -58 18 32 -165 10 25 -58 27 16 -161 51 17 -57 44 20 -167 56 11 -59 0 56 -164 46 7 -60 31 5 6 10 42 36 13 -15 -164 24 0 -60 26 30 -165 8 22 -60 35 40 -161 36 5 -59 50 36 -168 6 6 -61 11 0 -164 44 46 -62 45 54 6 10 58 34 12 -14 -164 20 53 -62 41 4 -165 8 48 -62 50 44 -161 20 16 -62 3 9 -168 21 33 -63 28 3 -164 46 35 -65 8 46 6 11 15 32 12 -14 -164 20 27 -65 3 37 -165 12 55 -65 13 55 -161 3 43 -64 23 15 -168 45 7 -65 53 38 -164 53 22 -67 41 38 6 11 31 29 11 -13 -164 24 14 -67 36 5 -165 22 47 -67 47 10 -160 46 17 -66 52 40 -169 21 27 -68 29 52 -165 8 38 -70 27 21 6 11 48 27 11 -12 -164 35 14 -70 21 18 -165 42 24 -70 33 23 -160 27 47 -69 33 55 -170 19 31 -71 19 55 -165 39 53 -73 30 21 6 12 4 24 12 -11 -164 59 55 -73 23 37 -166 20 29 -73 37 4 -160 8 3 -72 30 53 -171 59 26 -74 28 44 -166 47 3 -76 58 18 6 12 21 20 12 -10 -165 55 13 -76 50 34 -167 40 3 -77 6 0 -159 47 5 -75 50 0 -175 18 3 -78 4 50 -169 45 21 -81 6 30 6 12 37 16 15 -9 -168 24 20 -80 57 12 -171 9 39 -81 15 45 -159 26 2 -79 43 43 175 35 33 -82 24 2 172 36 9 -86 31 46 6 12 54 10 33 -6 177 20 57 -86 21 6 167 15 36 -86 41 26 -159 19 8 -84 43 16 108 6 32 -86 39 28 Uncertainty in time = +/- 17 secs Prediction of 2012 Aug 26.0 Data for the target star ------------------------ * name: UCAC2 29331807 * constellation : Scutum * J2000 position with proper motion to date of event [h,m,s ; °,',"] RA: 18 50 25.9928 DE: -07 26 03.772 * position source: mpos:UCAC2 pm:UCAC2 * standard error: RA,DE ["]: ( .078, .078 ) * V mag [mag]: 11.9 * B mag [mag]: 0.0 * Diameter [mas]: 0 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (1070) Tunica approx. diameter [km]: 39 approx. diameter ["]: .022 distance from Earth [AU]: 2.44300 * orbital information: orbit source: Preston date of fit: 2012 Aug 25 source of used astrometry: FASTT MPC (via Astdys) number of used observations: 958 number of rejected observations: 37 time covered by the observations: 1903 Sep 29 - 2012 Aug 07 1 sigma uncertainty ellipse (major, minor, PA): 0.037, 0.022, 93° remarks: * orbital elements for (1070) Tunica : Mean anomaly = 314.91562574 deg Arg. of pericenter = 185.27050074 deg Long. of node = 165.42258819 deg Inclination = 16.96394906 deg Eccentricity = 0.07974688 Semimajor axis = 3.23139446 AU Perihelion dist = 2.97370083 AU Mag: H = 10.66, G = 0.15 Epoch of elements : MJD 56175.25100000 TDT (2012 Sep 05.251) ------ occelmnt file for Occult BEGIN ----------------------------------- 2012 Sep 5 1070 Tunica 6h 2.2m UT 11.9 18 50 25.993- 7 26 3.77UCAC2 29331807 0.0 16.0 39 4.2 2.443 0.359 -17.96 -152.6893 -7.429 89.11 6.64 6.0363 -0.29716 -0.08817 1.48101 -4.99013 0.00497 -0.00032 2000 314.0246602012 831.00000185.270501165.422588 16.9639490.07974688 3.2313945 2.973700810.7 5.00.15 RATE 1.6967550 0.000000 0.000000 0.000000 0.0000000 0.0000000 0.0000000 Meas 0.086 0.081 91 4.89 0.086 0 0-2-2 056165.0020120905_331807 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2012 Aug 25, 22:27 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 425-688-9965 mailto: stevepr@acm.org