IOTA/IOTA-ES occultation update for (856) Backlunda / UCAC4 399-112651 event on 2023 Jun 08, 01:15 UT Visible from Europe Summary ------- On 2023 Jun 08 UT, the 45.2 km diameter asteroid (856) Backlunda will occult a 12.3 mag star in the constellation Aquila for observers along a path across Europe. In the case of an occultation, the combined light of the asteroid and the star will drop by 1.98 mag to 14.10 mag (the magnitude of the asteroid) for at most 6.800 seconds. This update is based on, astrometry for the asteroid kindly provided by the IAU Minor Planet Center. This work has made use of data from the European Space Agency (ESA) mission Gaia (http://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, http://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement. The event at a glimpse ---------------------- * Rank: 99 * date and approx. time of event: 2023 Jun 08, 01:08 - 2023 Jun 08, 01:23 * geocentric midpoint of event [JD]: 2460103.55262766 * magnitude of target star: 12.31 * magnitude drop [mag]: 1.98 * estimated maximum duration [s]: 6.800 * Moon: 80 % sunlit, 26° distance * Sun: 145° distance * rough path description: Europe The occultation path -------------------- * approximate projected width [km]: 101 * 1 sigma uncertainty interval [path widths]: +/- 0.21 * 1 sigma uncertainty interval [seconds]: +/- 2.1 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- 0.016, +/- 0.003) * 1 sigma uncertainty ellipse (major, minor, PA): (0.016", 0.003", 97°) * approx speed of asteroid's shadow [km/s]: 6.6458 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of UCAC4 399-112651 by 856 Backlunda on 2023 Jun 8 Centre Star Star Sun Path Limits Error Limits Alt E. Longitude Latitude U.T. Alt Az Alt Limit 1 Limit 2 Limit 3 Limit 4 Crn o ' " o ' " h m s o o o o ' " o ' " o ' " o ' " Latitude Latitude Latitude Latitude - 68 0 0 36 53 7 1 22 55.0 1 103 -16 37 21 50 36 24 52 37 33 48 36 13 24 .... - 67 0 0 36 43 6 1 22 54.4 1 104 -16 37 11 42 36 15 0 37 23 35 36 3 35 -1.34 - 66 0 0 36 34 0 1 22 53.5 2 105 -17 37 2 28 36 6 1 37 14 19 35 54 39 -1.60 - 65 0 0 36 25 49 1 22 52.1 3 105 -18 36 54 10 35 57 57 37 5 57 35 46 37 -1.72 - 64 0 0 36 18 32 1 22 50.3 4 106 -18 36 46 46 35 50 46 36 58 31 35 39 29 -1.78 - 63 0 0 36 12 9 1 22 48.1 5 106 -19 36 40 17 35 44 28 36 52 0 35 33 13 -1.83 - 62 0 0 36 6 39 1 22 45.4 5 107 -20 36 34 43 35 39 3 36 46 23 35 27 50 -1.86 - 61 0 0 36 2 2 1 22 42.4 6 108 -20 36 30 1 35 34 30 36 41 40 35 23 19 -1.88 - 60 0 0 35 58 18 1 22 38.9 7 108 -21 36 26 13 35 30 50 36 37 50 35 19 40 -1.89 - 59 0 0 35 55 27 1 22 35.1 8 109 -21 36 23 18 35 28 2 36 34 54 35 16 53 -1.91 - 58 0 0 35 53 27 1 22 30.9 9 109 -22 36 21 16 35 26 5 36 32 51 35 14 57 -1.92 - 57 0 0 35 52 20 1 22 26.2 9 110 -22 36 20 7 35 24 59 36 31 40 35 13 53 -1.92 - 56 0 0 35 52 4 1 22 21.2 10 111 -23 36 19 49 35 24 45 36 31 22 35 13 39 -1.93 - 55 0 0 35 52 40 1 22 15.9 11 111 -23 36 20 24 35 25 22 36 31 56 35 14 16 -1.93 - 54 0 0 35 54 6 1 22 10.1 11 112 -24 36 21 50 35 26 49 36 33 22 35 15 43 -1.94 - 53 0 0 35 56 24 1 22 4.0 12 112 -24 36 24 8 35 29 6 36 35 40 35 18 1 -1.94 - 52 0 0 35 59 32 1 21 57.6 13 113 -24 36 27 17 35 32 14 36 38 49 35 21 8 -1.95 - 51 0 0 36 3 31 1 21 50.8 14 114 -25 36 31 17 35 36 12 36 42 50 35 25 5 -1.95 - 50 0 0 36 8 20 1 21 43.6 14 114 -25 36 36 8 35 40 59 36 47 42 35 29 52 -1.95 - 49 0 0 36 14 0 1 21 36.1 15 115 -25 36 41 50 35 46 36 36 53 24 35 35 28 -1.95 - 48 0 0 36 20 29 1 21 28.3 16 116 -26 36 48 22 35 53 3 36 59 58 35 41 54 -1.95 - 47 0 0 36 27 48 1 21 20.2 16 116 -26 36 55 45 36 0 19 37 7 22 35 49 9 -1.96 - 46 0 0 36 35 57 1 21 11.7 17 117 -26 37 3 58 36 8 24 37 15 37 35 57 12 -1.96 - 45 0 0 36 44 55 1 21 3.0 18 118 -26 37 13 1 36 17 18 37 24 42 36 6 4 -1.96 - 44 0 0 36 54 43 1 20 53.9 18 119 -26 37 22 54 36 27 1 37 34 37 36 15 45 -1.96 - 43 0 0 37 5 21 1 20 44.5 19 119 -27 37 33 37 36 37 33 37 45 23 36 26 15 -1.96 - 42 0 0 37 16 47 1 20 34.9 19 120 -27 37 45 10 36 48 53 37 56 58 36 37 33 -1.96 - 41 0 0 37 29 3 1 20 24.9 20 121 -27 37 57 32 37 1 2 38 9 24 36 49 39 -1.96 - 40 0 0 37 42 7 1 20 14.7 20 122 -27 38 10 45 37 13 59 38 22 40 37 2 34 -1.96 - 39 0 0 37 56 1 1 20 4.2 21 123 -27 38 24 47 37 27 45 38 36 45 37 16 17 -1.97 - 38 0 0 38 10 44 1 19 53.5 21 123 -27 38 39 39 37 42 20 38 51 41 37 30 48 -1.97 - 37 0 0 38 26 16 1 19 42.5 22 124 -27 38 55 20 37 57 42 39 7 26 37 46 7 -1.97 - 36 0 0 38 42 37 1 19 31.3 22 125 -27 39 11 51 38 13 53 39 24 2 38 2 14 -1.97 - 35 0 0 38 59 46 1 19 19.8 23 126 -27 39 29 12 38 30 52 39 41 27 38 19 9 -1.97 - 34 0 0 39 17 45 1 19 8.1 23 127 -27 39 47 22 38 48 40 39 59 42 38 36 52 -1.97 - 33 0 0 39 36 32 1 18 56.2 24 128 -27 40 6 22 39 7 15 40 18 48 38 55 23 -1.98 - 32 0 0 39 56 8 1 18 44.1 24 129 -26 40 26 12 39 26 39 40 38 43 39 14 41 -1.98 - 31 0 0 40 16 34 1 18 31.7 24 130 -26 40 46 51 39 46 51 40 59 29 39 34 48 -1.98 - 30 0 0 40 37 48 1 18 19.2 25 131 -26 41 8 21 40 7 51 41 21 5 39 55 43 -1.98 - 29 0 0 40 59 51 1 18 6.5 25 131 -26 41 30 40 40 29 40 41 43 31 40 17 25 -1.98 - 28 0 0 41 22 44 1 17 53.6 25 132 -26 41 53 49 40 52 16 42 6 48 40 39 56 -1.99 - 27 0 0 41 46 26 1 17 40.6 25 133 -25 42 17 49 41 15 42 42 30 55 41 3 14 -1.99 - 26 0 0 42 10 57 1 17 27.4 26 134 -25 42 42 39 41 39 55 42 55 53 41 27 21 -1.99 - 25 0 0 42 36 18 1 17 14.1 26 135 -25 43 8 19 42 4 57 43 21 42 41 52 15 -1.99 - 24 0 0 43 2 27 1 17 0.6 26 136 -24 43 34 50 42 30 47 43 48 22 42 17 58 -2.00 - 23 0 0 43 29 27 1 16 47.0 26 138 -24 44 2 12 42 57 26 44 15 54 42 44 28 -2.00 - 22 0 0 43 57 16 1 16 33.3 26 139 -23 44 30 25 43 24 53 44 44 17 43 11 47 -2.00 - 21 0 0 44 25 56 1 16 19.5 26 140 -23 44 59 29 43 53 9 45 13 32 43 39 54 -2.00 - 20 0 0 44 55 25 1 16 5.6 26 141 -22 45 29 25 44 22 14 45 43 39 44 8 50 -2.01 - 19 0 0 45 25 45 1 15 51.6 26 142 -22 46 0 13 44 52 9 46 14 38 44 38 34 -2.01 - 18 0 0 45 56 55 1 15 37.5 26 143 -21 46 31 52 45 22 52 46 46 30 45 9 6 -2.01 - 17 0 0 46 28 56 1 15 23.4 26 144 -21 47 4 24 45 54 24 47 19 16 45 40 27 -2.02 - 16 0 0 47 1 48 1 15 9.3 26 145 -20 47 37 49 46 26 45 47 52 55 46 12 37 -2.02 - 15 0 0 47 35 31 1 14 55.1 26 146 -20 48 12 7 46 59 56 48 27 28 46 45 36 -2.02 - 14 0 0 48 10 6 1 14 41.0 26 147 -19 48 47 18 47 33 57 49 2 56 47 19 23 -2.03 - 13 0 0 48 45 32 1 14 26.8 26 148 -18 49 23 24 48 8 48 49 39 19 47 54 0 -2.03 - 12 0 0 49 21 51 1 14 12.6 26 150 -18 50 0 24 48 44 29 50 16 37 48 29 26 -2.03 - 11 0 0 49 59 2 1 13 58.5 25 151 -17 50 38 19 49 21 0 50 54 52 49 5 42 -2.04 - 10 0 0 50 37 6 1 13 44.4 25 152 -16 51 17 11 49 58 21 51 34 5 49 42 47 -2.04 - 9 0 0 51 16 4 1 13 30.4 25 153 -16 51 56 59 50 36 34 52 14 15 50 20 43 -2.05 - 8 0 0 51 55 56 1 13 16.5 25 154 -15 52 37 45 51 15 38 52 55 25 50 59 28 -2.05 - 7 0 0 52 36 43 1 13 2.6 24 155 -14 53 19 29 51 55 33 53 37 34 51 39 4 -2.05 - 6 0 0 53 18 25 1 12 48.9 24 156 -13 54 2 12 52 36 21 54 20 45 52 19 31 -2.06 - 5 0 0 54 1 3 1 12 35.3 23 157 -12 54 45 56 53 18 0 55 4 59 53 0 48 -2.06 - 4 0 0 54 44 37 1 12 21.8 23 158 -12 55 30 42 54 0 33 55 50 17 53 42 57 -2.07 - 3 0 0 55 29 10 1 12 8.5 22 160 -11 56 16 32 54 43 58 56 36 42 54 25 57 -2.07 - 2 0 0 56 14 42 1 11 55.4 22 161 -10 57 3 26 55 28 18 57 24 15 55 9 50 -2.07 - 1 0 0 57 1 13 1 11 42.5 21 162 -9 57 51 28 56 13 32 58 12 59 55 54 35 -2.08 0 0 0 57 48 46 1 11 29.7 21 163 -8 58 40 40 56 59 41 59 2 56 56 40 14 -2.08 1 0 0 58 37 22 1 11 17.3 20 164 -7 59 31 4 57 46 47 59 54 10 57 26 46 -2.09 2 0 0 59 27 3 1 11 5.1 19 165 -6 60 22 43 58 34 49 60 46 46 58 14 12 -2.09 3 0 0 60 17 51 1 10 53.1 19 166 -5 61 15 42 59 23 49 61 40 48 59 2 33 -2.10 4 0 0 61 9 49 1 10 41.5 18 167 -4 62 10 6 60 13 49 62 36 23 59 51 51 -2.10 5 0 0 62 3 0 1 10 30.2 17 168 -3 63 6 0 61 4 50 63 33 38 60 42 5 -2.11 6 0 0 62 57 27 1 10 19.3 16 169 -2 64 3 33 61 56 53 64 32 43 61 33 18 -2.11 7 0 0 63 53 16 1 10 8.7 16 170 -1 65 2 53 62 50 2 65 33 51 62 25 31 -2.12 8 0 0 64 50 32 1 9 58.5 15 171 0 66 4 12 63 44 18 66 37 20 63 18 46 -2.12 9 0 0 65 49 23 1 9 48.7 14 172 1 67 7 48 64 39 45 67 43 32 64 13 5 -2.13 10 0 0 66 49 57 1 9 39.4 13 173 2 68 14 4 65 36 27 68 53 2 65 8 30 -2.14 11 0 0 67 52 28 1 9 30.5 12 174 3 69 23 31 66 34 28 70 6 41 66 5 5 -2.14 12 0 0 68 57 12 1 9 22.2 11 175 4 70 37 0 67 33 55 71 25 56 67 2 54 -2.16 13 0 0 70 4 33 1 9 14.4 10 176 5 71 55 54 68 34 56 72 53 27 68 2 1 -2.17 14 0 0 71 15 5 1 9 7.2 8 177 6 73 22 49 69 37 43 74 35 34 69 2 35 -2.19 15 0 0 72 29 44 1 9 0.6 7 178 8 75 3 42 70 42 28 76 58 44 70 4 43 -2.22 16 0 0 73 50 2 1 8 54.8 6 179 9 77 23 5 71 49 34 .. .. .. 71 8 39 -2.27 17 0 0 75 19 5 1 8 49.7 4 180 10 .. .. .. 72 59 32 .. .. .. 72 14 38 -2.37 18 0 0 77 4 57 1 8 45.6 3 181 12 .. .. .. 74 13 9 .. .. .. 73 23 5 -2.69 19 0 0 .. .. .... .. .. .. .. .. .. .. .. .. 75 31 48 .. .. .. 74 34 37 .... 20 0 0 .. .. .... .. .. .. .. .. .. .. .. .. 76 58 13 .. .. .. 75 50 16 .... 21 0 0 .. .. .... .. .. .. .. .. .. .. .. .. 78 39 20 .. .. .. 77 11 56 .... 22 0 0 .. .. .... .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 78 43 54 .... Uncertainty in time = +/- 3 secs Prediction of 2023 Apr 29.2 Data for the target star ------------------------ * name: UCAC4 399-112651 * constellation : Aquila * BCRS position with proper motion to date of event [h,m,s ; °,',"] RA: 19 20 02.1987 DE: -10 22 27.216 * GCRS Astrometric position with proper motion and parallax to date of event [h,m,s ; °,',"] RA: 19 20 02.1987 DE: -10 22 27.216 * position source: Gaia DR3 * standard error: RA,DE [mas]: (0.100,0.100) * V mag [mag]: 12.3 * Diameter [mas]: 0.00 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (856) Backlunda asteroid class: approx. diameter [km]: 45 approx. diameter ["]: 0.043 distance from Earth [AU]: 1.43490 asteroid position offset in RA [mas]: 0 asteroid position offset in DE [mas]: 0 * orbital information: orbit source: JPL#94 date of fit: 2023 Apr 24 source of used astrometry: MPC, JPL number of used observations: 0 number of rejected observations: 0 time covered by the observations: 1800 Jan 01 - 1800 Jan 01 1 sigma uncertainty ellipse (major, minor, PA): 0.016", 0.003", 96.873° remarks: * orbital elements for (856)Backlunda : Mean anomaly = 64.2036348872 deg Arg. of pericenter = 72.6306929116 deg Long. of node = 125.5326916712 deg Inclination = 14.3267231937 deg Eccentricity = 0.1191770211 Semimajor axis = 2.4350616895 AU Perihelion dist = 2.1448582911 AU Mag: H = 10.66, G = 0.15 Epoch of elements : MJD 60103.05256944 TDT (2023 Jun 08.0526) ------ occelmnt file for Occult BEGIN ----------------------------------- JPL#942023Apr24,6.80,2023,6,8,1.263064,-0.390840,0.803686,-3.373229,-1.640664,-0.002812,-0.001307,0.000001,0.000000 15.2150,-10.3315,160.80,22.81,False UCAC4 399-112651,19.33394407,-10.3742268,0.00,12.31,0.00,0.0,0,,19.35561059,-10.3314504,1.98,0.00,0,0,0 856,Backlunda,14.10,45.2,1.4349,0,0,-1.401,-10.06,,2.6,0 0,63.9306,2023,6,7,72.6307,125.5327,14.3267,0.11918,2.43506,2.14486,10.66,5.0,0.15 1.206,0.0160,0.0025,97,0.0089,Known errors,-1.00,-1,-1,-1 20230608_112651,60063.19 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2023 Apr 29, 04:36 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 stevepr@acm.org