IOTA/IOTA-ES occultation update for (118379) 1999 HC12 / TYC 6800-01411-1 event on 2023 Feb 12, 18:39 UT Visible from Summary ------- On 2023 Feb 12 UT, the 100 km diameter asteroid (118379) 1999 HC12 will occult a 11.5 mag star in the constellation Scorpius for observers along a path across . In the case of an occultation, the combined light of the asteroid and the star will drop by 12.78 mag to 24.26 mag (the magnitude of the asteroid) for at most 6.920 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: 0 * date and approx. time of event: predicted path center does not land on Earth. * geocentric midpoint of event [JD]: 2459988.22699312 * magnitude of target star: 11.48 * magnitude drop [mag]: 12.78 * estimated maximum duration [s]: 6.920 * Moon: 60 % sunlit, 30° distance * Sun: 71° distance * rough path description: The occultation path -------------------- * approximate projected width [km]: 100 * 1 sigma uncertainty interval [path widths]: +/- 1054.51 * 1 sigma uncertainty interval [seconds]: +/- 84137.6 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- 35.020, +/- 14.612) * 1 sigma uncertainty ellipse (major, minor, PA): (37.854", 2.645", 112°) * approx speed of asteroid's shadow [km/s]: 14.4405 * website for maps: http://www.asteroidoccultation.com Path Coordinates: No Lat/Long file for this path. Data for the target star ------------------------ * name: TYC 6800-01411-1 * constellation : Scorpius * BCRS position with proper motion to date of event [h,m,s ; °,',"] RA: 16 39 41.3349 DE: -25 53 32.379 * GCRS Astrometric position with proper motion and parallax to date of event [h,m,s ; °,',"] RA: 16 39 41.3350 DE: -25 53 32.380 * position source: Gaia DR3 * standard error: RA,DE [mas]: (0.200,0.100) * V mag [mag]: 11.5 * Diameter [mas]: 0.00 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (118379) 1999 HC12 asteroid class: TNO approx. diameter [km]: 100 approx. diameter ["]: 0.003 distance from Earth [AU]: 44.72870 asteroid position offset in RA [mas]: 0 asteroid position offset in DE [mas]: 0 * orbital information: orbit source: JPL#4 date of fit: 2021 Apr 13 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): 37.854", 2.645", 112.369° remarks: * orbital elements for (118379)1999 HC12 : Mean anomaly = 72.7970024785 deg Arg. of pericenter = 94.7006826912 deg Long. of node = 57.0675457231 deg Inclination = 15.3812269589 deg Eccentricity = 0.2314376891 Semimajor axis = 45.1450456731 AU Perihelion dist = 34.6967806286 AU Mag: H = 7.58, G = 0.15 Epoch of elements : MJD 59987.77743056 TDT (2023 Feb 12.7774) ------ occelmnt file for Occult BEGIN ----------------------------------- JPL#42021Apr13,6.92,2023,2,12,17.447835,-0.532606,-1.495887,7.679080,-2.732092,-0.005808,0.000659,-0.000001,0.000000 -153.9483,-25.9371,-78.17,-13.61,False TYC 6800-01411-1,16.66148193,-25.8923276,0.00,11.48,0.00,0.0,0,,16.68479765,-25.9371190,12.78,0.00,0,0,0 118379,1999 HC12,24.26,100.0,44.7287,0,0,0.113,-0.54,,10.0 0,72.7945,2023,2,12,94.7007,57.0675,15.3812,0.23144,45.14505,34.69678,7.60,5.0,0.15 1055.513,37.8540,2.6450,112,3.2506,Known errors,-1.00,-1,-1,-1 20230212_1411-1,59744.95 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2022 Jun 14, 22:50 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 stevepr@acm.org