IOTA/IOTA-ES occultation update for (501) Urhixidur / UCAC4-619-045455 event on 2021 Jan 10, 05:42 UT Visible from South America Summary ------- On 2021 Jan 10 UT, the 77.7 km diameter asteroid (501) Urhixidur will occult a 12.3 mag star in the constellation Leo Minor for observers along a path across South America. In the case of an occultation, the combined light of the asteroid and the star will drop by 2.60 mag to 14.81 mag (the magnitude of the asteroid) for at most 6.5 seconds. This update is based on UNSO/Flagstaff astrometry for the asteroid kindly provided by Hugh Harris, astrometry for the asteroid kindly provided by Bill Owen, 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: 97 * date and approx. time of event: 2021 Jan 10, 05:37 - 2021 Jan 10, 05:49 * geocentric midpoint of event [JD]: 2459224.73835000 * magnitude of target star: 12.31 * magnitude drop [mag]: 2.60 * estimated maximum duration [s]: 6.5 * Moon: 11 % sunlit, 110° distance * Sun: 144° distance * rough path description: South America The occultation path -------------------- * approximate projected width [km]: 125 * 1 sigma uncertainty interval [path widths]: +/- 0.38 * 1 sigma uncertainty interval [seconds]: +/- 3.6 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- 0.020, +/- 0.018) * 1 sigma uncertainty ellipse (major, minor, PA): (0.023", 0.015", 128°) * approx speed of asteroid's shadow [km/s]: 11.9499 * website for maps: http://www.asteroidoccultation.com Path Coordinates: Occultation of UCAC4-619-045455 by 501 Urhixidur on 2021 Jan 10 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 ' " Longitude Longitude Longitude Longitude - 20 39 20 -54 0 0 5 37 42.4 0 341 2 - 19 37 46 - 21 41 28 ... .. .. - 22 28 49 .... - 21 15 9 -53 0 0 5 37 42.6 1 341 2 - 20 14 40 - 22 16 12 ... .. .. - 23 2 44 0.54 - 21 51 55 -52 0 0 5 37 43.0 2 342 1 - 20 52 25 - 22 51 58 - 20 7 49 - 23 37 44 0.88 - 22 29 37 -51 0 0 5 37 43.8 3 342 0 - 21 31 2 - 23 28 45 - 20 47 7 - 24 13 49 1.01 - 23 8 15 -50 0 0 5 37 44.9 5 343 -1 - 22 10 30 - 24 6 33 - 21 27 13 - 24 50 59 1.08 - 23 47 50 -49 0 0 5 37 46.3 6 343 -2 - 22 50 51 - 24 45 22 - 22 8 9 - 25 29 13 1.12 - 24 28 22 -48 0 0 5 37 48.0 7 344 -3 - 23 32 5 - 25 25 12 - 22 49 55 - 26 8 31 1.15 - 25 9 52 -47 0 0 5 37 50.0 8 344 -4 - 24 14 13 - 26 6 4 - 23 32 31 - 26 48 55 1.17 - 25 52 21 -46 0 0 5 37 52.4 9 345 -5 - 24 57 16 - 26 47 59 - 24 16 1 - 27 30 24 1.19 - 26 35 50 -45 0 0 5 37 55.1 10 346 -6 - 25 41 16 - 27 30 58 - 25 0 24 - 28 13 0 1.20 - 27 20 21 -44 0 0 5 37 58.1 11 346 -7 - 26 26 14 - 28 15 2 - 25 45 43 - 28 56 45 1.21 - 28 5 55 -43 0 0 5 38 1.5 12 347 -8 - 27 12 12 - 29 0 13 - 26 31 59 - 29 41 39 1.22 - 28 52 35 -42 0 0 5 38 5.3 13 347 -9 - 27 59 12 - 29 46 33 - 27 19 14 - 30 27 44 1.23 - 29 40 22 -41 0 0 5 38 9.4 14 348 -10 - 28 47 16 - 30 34 4 - 28 7 31 - 31 15 4 1.23 - 30 29 20 -40 0 0 5 38 13.8 15 348 -11 - 29 36 27 - 31 22 49 - 28 56 53 - 32 3 39 1.24 - 31 19 30 -39 0 0 5 38 18.7 17 349 -13 - 30 26 48 - 32 12 50 - 29 47 22 - 32 53 34 1.24 - 32 10 56 -38 0 0 5 38 23.9 18 350 -14 - 31 18 20 - 33 4 11 - 30 39 0 - 33 44 51 1.25 - 33 3 42 -37 0 0 5 38 29.5 19 350 -15 - 32 11 9 - 33 56 54 - 31 31 52 - 34 37 34 1.25 - 33 57 51 -36 0 0 5 38 35.6 20 351 -16 - 33 5 18 - 34 51 5 - 32 26 1 - 35 31 47 1.25 - 34 53 28 -35 0 0 5 38 42.0 21 352 -17 - 34 0 51 - 35 46 48 - 33 21 31 - 36 27 34 1.25 - 35 50 37 -34 0 0 5 38 48.9 22 353 -19 - 34 57 52 - 36 44 7 - 34 18 27 - 37 25 2 1.25 - 36 49 24 -33 0 0 5 38 56.2 23 353 -20 - 35 56 26 - 37 43 8 - 35 16 54 - 38 24 15 1.26 - 37 49 55 -32 0 0 5 39 4.0 24 354 -21 - 36 56 41 - 38 43 57 - 36 16 57 - 39 25 20 1.26 - 38 52 17 -31 0 0 5 39 12.2 25 355 -22 - 37 58 41 - 39 46 42 - 37 18 42 - 40 28 25 1.26 - 39 56 36 -30 0 0 5 39 20.9 26 356 -24 - 39 2 34 - 40 51 31 - 38 22 17 - 41 33 37 1.26 - 41 3 3 -29 0 0 5 39 30.1 27 357 -25 - 40 8 28 - 41 58 33 - 39 27 49 - 42 41 8 1.26 - 42 11 46 -28 0 0 5 39 39.9 28 358 -26 - 41 16 33 - 43 7 58 - 40 35 27 - 43 51 7 1.26 - 43 22 58 -27 0 0 5 39 50.2 29 359 -28 - 42 26 59 - 44 19 59 - 41 45 21 - 45 3 48 1.26 - 44 36 50 -26 0 0 5 40 1.0 30 0 -29 - 43 39 59 - 45 34 49 - 42 57 43 - 46 19 26 1.26 - 45 53 39 -25 0 0 5 40 12.5 31 1 -31 - 44 55 45 - 46 52 46 - 44 12 46 - 47 38 18 1.26 - 47 13 42 -24 0 0 5 40 24.7 32 3 -32 - 46 14 36 - 48 14 9 - 45 30 46 - 49 0 46 1.26 - 48 37 21 -23 0 0 5 40 37.6 33 4 -34 - 47 36 49 - 49 39 21 - 46 52 0 - 50 27 14 1.26 - 50 5 1 -22 0 0 5 40 51.2 34 6 -36 - 49 2 49 - 51 8 50 - 48 16 50 - 51 58 15 1.26 - 51 37 13 -21 0 0 5 41 5.6 35 7 -37 - 50 33 4 - 52 43 13 - 49 45 43 - 53 34 26 1.26 - 53 14 38 -20 0 0 5 41 21.0 36 9 -39 - 52 8 8 - 54 23 14 - 51 19 11 - 55 16 37 1.26 - 54 58 4 -19 0 0 5 41 37.3 37 11 -41 - 53 48 45 - 56 9 50 - 52 57 52 - 57 5 52 1.26 - 56 48 36 -18 0 0 5 41 54.9 37 13 -42 - 55 35 51 - 58 4 17 - 54 42 37 - 59 3 39 1.26 - 58 47 43 -17 0 0 5 42 13.8 38 15 -44 - 57 30 40 - 60 8 21 - 56 34 33 - 61 12 0 1.26 - 60 57 28 -16 0 0 5 42 34.3 38 17 -46 - 59 34 55 - 62 24 35 - 58 35 8 - 63 33 58 1.26 Latitude Latitude Latitude Latitude - 62 0 0 -15 33 2 5 42 44.1 38 18 -47 -14 56 15 -16 10 23 -14 28 48 -16 38 59 1.26 - 63 0 0 -15 8 21 5 42 53.5 38 19 -48 -14 31 50 -15 45 23 -14 4 35 -16 13 45 1.26 - 64 0 0 -14 44 47 5 43 2.9 38 20 -49 -14 8 32 -15 21 34 -13 41 29 -15 49 43 1.26 - 65 0 0 -14 22 22 5 43 12.2 38 21 -49 -13 46 22 -14 58 52 -13 19 29 -15 26 49 1.26 - 66 0 0 -14 1 3 5 43 21.5 38 22 -50 -13 25 17 -14 37 19 -12 58 35 -15 5 5 1.26 - 67 0 0 -13 40 51 5 43 30.7 38 23 -51 -13 5 18 -14 16 54 -12 38 46 -14 44 28 1.26 - 68 0 0 -13 21 45 5 43 39.9 38 24 -51 -12 46 24 -13 57 35 -12 20 1 -14 24 59 1.26 - 69 0 0 -13 3 44 5 43 49.0 38 25 -52 -12 28 35 -13 39 22 -12 2 20 -14 6 37 1.26 - 70 0 0 -12 46 48 5 43 58.1 38 26 -53 -12 11 50 -13 22 15 -11 45 42 -13 49 22 1.26 - 71 0 0 -12 30 57 5 44 7.1 38 27 -53 -11 56 8 -13 6 13 -11 30 8 -13 33 12 1.26 - 72 0 0 -12 16 9 5 44 16.0 38 28 -54 -11 41 29 -12 51 16 -11 15 36 -13 18 7 1.26 - 73 0 0 -12 2 25 5 44 24.8 37 29 -54 -11 27 54 -12 37 23 -11 2 6 -13 4 8 1.26 - 74 0 0 -11 49 44 5 44 33.6 37 30 -55 -11 15 21 -12 24 35 -10 49 39 -12 51 13 1.26 - 75 0 0 -11 38 6 5 44 42.2 37 31 -55 -11 3 50 -12 12 49 -10 38 13 -12 39 22 1.26 - 76 0 0 -11 27 31 5 44 50.8 36 32 -56 -10 53 21 -12 2 8 -10 27 48 -12 28 35 1.26 - 77 0 0 -11 17 58 5 44 59.3 36 32 -56 -10 43 53 -11 52 29 -10 18 25 -12 18 52 1.26 - 78 0 0 -11 9 27 5 45 7.7 36 33 -56 -10 35 27 -11 43 53 -10 10 2 -12 10 12 1.26 - 79 0 0 -11 1 58 5 45 16.0 35 34 -57 -10 28 2 -11 36 20 -10 2 41 -12 2 35 1.26 - 80 0 0 -10 55 31 5 45 24.2 35 35 -57 -10 21 39 -11 29 49 - 9 56 20 -11 56 1 1.27 - 81 0 0 -10 50 5 5 45 32.3 34 36 -57 -10 16 16 -11 24 20 - 9 50 59 -11 50 30 1.27 - 82 0 0 -10 45 41 5 45 40.3 34 36 -57 -10 11 54 -11 19 54 - 9 46 39 -11 46 2 1.27 - 83 0 0 -10 42 19 5 45 48.2 33 37 -57 -10 8 33 -11 16 30 - 9 43 19 -11 42 37 1.27 - 84 0 0 -10 39 58 5 45 56.0 33 38 -57 -10 6 13 -11 14 8 - 9 41 0 -11 40 14 1.27 - 85 0 0 -10 38 39 5 46 3.6 32 38 -57 -10 4 54 -11 12 48 - 9 39 41 -11 38 54 1.27 - 86 0 0 -10 38 21 5 46 11.2 32 39 -57 -10 4 36 -11 12 31 - 9 39 23 -11 38 37 1.27 - 87 0 0 -10 39 5 5 46 18.6 31 40 -57 -10 5 19 -11 13 16 - 9 40 5 -11 39 23 1.27 - 88 0 0 -10 40 50 5 46 25.8 30 40 -57 -10 7 3 -11 15 3 - 9 41 47 -11 41 12 1.27 - 89 0 0 -10 43 38 5 46 33.0 30 41 -57 -10 9 48 -11 17 53 - 9 44 31 -11 44 4 1.27 - 90 0 0 -10 47 27 5 46 40.0 29 41 -57 -10 13 35 -11 21 46 - 9 48 15 -11 47 59 1.28 - 91 0 0 -10 52 20 5 46 46.9 28 42 -57 -10 18 23 -11 26 42 - 9 53 1 -11 52 58 1.28 - 92 0 0 -10 58 14 5 46 53.6 28 42 -56 -10 24 14 -11 32 41 - 9 58 48 -11 59 0 1.28 - 93 0 0 -11 5 12 5 47 0.2 27 43 -56 -10 31 6 -11 39 44 -10 5 37 -12 6 7 1.28 - 94 0 0 -11 13 13 5 47 6.7 26 43 -56 -10 39 1 -11 47 51 -10 13 28 -12 14 19 1.28 - 95 0 0 -11 22 17 5 47 13.0 25 44 -55 -10 47 59 -11 57 2 -10 22 22 -12 23 35 1.28 - 96 0 0 -11 32 26 5 47 19.1 25 44 -55 -10 58 1 -12 7 18 -10 32 18 -12 33 57 1.28 - 97 0 0 -11 43 39 5 47 25.0 24 45 -54 -11 9 6 -12 18 39 -10 43 17 -12 45 25 1.29 - 98 0 0 -11 55 57 5 47 30.8 23 45 -54 -11 21 16 -12 31 6 -10 55 21 -12 57 59 1.29 - 99 0 0 -12 9 21 5 47 36.5 22 46 -53 -11 34 30 -12 44 40 -11 8 28 -13 11 40 1.29 -100 0 0 -12 23 51 5 47 41.9 21 46 -53 -11 48 50 -12 59 20 -11 22 40 -13 26 29 1.29 -101 0 0 -12 39 27 5 47 47.2 20 46 -52 -12 4 15 -13 15 8 -11 37 58 -13 42 26 1.29 -102 0 0 -12 56 11 5 47 52.2 19 47 -51 -12 20 47 -13 32 5 -11 54 21 -13 59 32 1.30 -103 0 0 -13 14 4 5 47 57.1 19 47 -51 -12 38 27 -13 50 10 -12 11 51 -14 17 48 1.30 -104 0 0 -13 33 5 5 48 1.8 18 48 -50 -12 57 14 -14 9 26 -12 30 29 -14 37 15 1.30 -105 0 0 -13 53 15 5 48 6.3 17 48 -49 -13 17 10 -14 29 51 -12 50 14 -14 57 52 1.30 -106 0 0 -14 14 36 5 48 10.5 16 48 -49 -13 38 16 -14 51 29 -13 11 8 -15 19 43 1.31 -107 0 0 -14 37 9 5 48 14.6 15 49 -48 -14 0 32 -15 14 19 -13 33 12 -15 42 46 1.31 -108 0 0 -15 0 54 5 48 18.4 14 49 -47 -14 23 59 -15 38 22 -13 56 26 -16 7 4 1.31 -109 0 0 -15 25 52 5 48 22.0 13 49 -46 -14 48 38 -16 3 39 -14 20 52 -16 32 37 1.32 -110 0 0 -15 52 4 5 48 25.3 12 50 -45 -15 14 31 -16 30 13 -14 46 30 -16 59 26 1.32 -111 0 0 -16 19 32 5 48 28.4 11 50 -44 -15 41 37 -16 58 2 -15 13 22 -17 27 33 1.33 -112 0 0 -16 48 16 5 48 31.3 10 50 -43 -16 9 59 -17 27 10 -15 41 27 -17 57 0 1.33 -113 0 0 -17 18 18 5 48 33.8 9 51 -42 -16 39 38 -17 57 37 -16 10 49 -18 27 46 1.34 -114 0 0 -17 49 39 5 48 36.1 8 51 -41 -17 10 33 -18 29 24 -16 41 27 -18 59 54 1.35 -115 0 0 -18 22 20 5 48 38.2 7 51 -40 -17 42 48 -19 2 33 -17 13 22 -19 33 25 1.36 -116 0 0 -18 56 23 5 48 39.9 6 52 -39 -18 16 23 -19 37 5 -17 46 37 -20 8 21 1.37 -117 0 0 -19 31 49 5 48 41.3 4 52 -38 -18 51 19 -20 13 2 -18 21 11 -20 44 42 1.40 -118 0 0 -20 8 39 5 48 42.4 3 52 -37 -19 27 38 -20 50 26 -18 57 8 -21 22 32 1.43 -119 0 0 -20 46 55 5 48 43.2 2 53 -36 -20 5 21 -21 29 17 .. .. .. -22 1 51 1.51 -120 0 0 -21 26 39 5 48 43.7 1 53 -35 -20 44 30 -22 9 38 .. .. .. -22 42 42 1.74 Uncertainty in time = +/- 4 secs Prediction of 2020 Dec 31.0 Data for the target star ------------------------ * name: UCAC4-619-045455 * constellation : Leo Minor * BCRS position with proper motion to date of event [h,m,s ; °,',"] RA: 10 01 22.1340 DE: +33 47 01.435 * GCRS Astrometric position with proper motion and parallax to date of event [h,m,s ; °,',"] RA: 10 01 22.1342 DE: +33 47 01.435 * position source: Gaia EDR3 * 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: (501) Urhixidur asteroid class: approx. diameter [km]: 78 approx. diameter ["]: 0.041 distance from Earth [AU]: 2.61050 asteroid position offset in RA [mas]: 0 asteroid position offset in DE [mas]: 0 * orbital information: orbit source: Preston date of fit: 2020 Nov 14 source of used astrometry: MPC, FASTT, TMO number of used observations: 2536 number of rejected observations: 4 time covered by the observations: 1960 Feb 01 - 2020 Oct 20 1 sigma uncertainty ellipse (major, minor, PA): 0.023", 0.015", 127.9° remarks: * orbital elements for (501)Urhixidur : Mean anomaly = 124.33651007 deg Arg. of pericenter = 356.18191614 deg Long. of node = 357.23570840 deg Inclination = 20.83583131 deg Eccentricity = 0.14135506 Semimajor axis = 3.16406305 AU Perihelion dist = 2.71680673 AU Mag: H = 9.40, G = 0.15 Epoch of elements : MJD 59224.23800000 TDT (2021 Jan 10.2380) ------ occelmnt file for Occult BEGIN ----------------------------------- Preston2020Nov14,6.5,2021,1,10,5.7204,-0.33147,-0.70959,-6.11787,2.83982,-0.00357,-0.00054,0.00000,0.00000 -45.1255,33.6808,96.08,-21.92,False UCAC4-619-045455,10.02281505,33.7837320,0.00,12.31,0.00,0.0,0,,10.04338592,33.6808069 501,Urhixidur,14.81,77.7,2.6105,0,0,-1.651,9.56,,3.8 0,124.2948,2021,1,10,356.1819,357.2357,20.8358,0.14136,3.16406,2.71681,9.40,5.0,0.15 1.378,0.0230,0.0150,128,0.0155,Known errors 20210110_045455,59214.00 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2020 Dec 31, 00:33 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 stevepr@acm.org