IOTA/IOTA-ES occultation update for (91133) 1998 HK151 / UCAC4 313-244166 event on 2023 Oct 30, 15:50 UT Visible from Summary ------- On 2023 Oct 30 UT, the 100 km diameter asteroid (91133) 1998 HK151 will occult a 12.9 mag star in the constellation Sagittarius for observers along a path across . In the case of an occultation, the combined light of the asteroid and the star will drop by 10.09 mag to 23.03 mag (the magnitude of the asteroid) for at most 5.860 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]: 2460248.54968225 * magnitude of target star: 12.94 * magnitude drop [mag]: 10.09 * estimated maximum duration [s]: 5.860 * Moon: 94 % sunlit, 140° distance * Sun: 69° distance * rough path description: The occultation path -------------------- * approximate projected width [km]: 100 * 1 sigma uncertainty interval [path widths]: +/- 4790.26 * 1 sigma uncertainty interval [seconds]: +/- 151388.1 * 1 sigma uncertainty interval approx RA,DE ["]: (+/- 107.763, +/- 6.788) * 1 sigma uncertainty ellipse (major, minor, PA): (107.963", 1.738", 87°) * approx speed of asteroid's shadow [km/s]: 17.0643 * website for maps: http://www.asteroidoccultation.com Path Coordinates: No Lat/Long file for this path. Data for the target star ------------------------ * name: UCAC4 313-244166 * constellation : Sagittarius * BCRS position with proper motion to date of event [h,m,s ; °,',"] RA: 19 09 42.2996 DE: -27 26 10.271 * GCRS Astrometric position with proper motion and parallax to date of event [h,m,s ; °,',"] RA: 19 09 42.2996 DE: -27 26 10.271 * position source: Gaia DR3 * standard error: RA,DE [mas]: (0.200,0.200) * V mag [mag]: 12.9 * Diameter [mas]: 0.00 * remarks: Data for the minor planet ------------------------- * general information: (number) name: (91133) 1998 HK151 asteroid class: TNO approx. diameter [km]: 100 approx. diameter ["]: 0.004 distance from Earth [AU]: 33.44860 asteroid position offset in RA [mas]: 0 asteroid position offset in DE [mas]: 0 * orbital information: orbit source: JPL#9 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): 107.963", 1.738", 86.515° remarks: * orbital elements for (91133)1998 HK151 : Mean anomaly = 36.3482871976 deg Arg. of pericenter = 181.0940316250 deg Long. of node = 50.3616759710 deg Inclination = 5.9495225600 deg Eccentricity = 0.2260034536 Semimajor axis = 39.3183352871 AU Perihelion dist = 30.4322557242 AU Mag: H = 7.62, G = 0.15 Epoch of elements : MJD 60247.66034722 TDT (2023 Oct 30.6603) ------ occelmnt file for Occult BEGIN ----------------------------------- JPL#92021Apr13,5.86,2023,10,31,1.192374,-5.100169,20.556424,9.348264,2.318781,0.005642,0.000499,0.000000,0.000000 -129.1824,-27.3993,158.03,-13.96,False UCAC4 313-244166,19.16174988,-27.4361864,0.00,12.94,0.00,0.0,0,,19.18616811,-27.3992774,10.09,0.00,0,0,0 91133,1998 HK151,23.03,100.0,33.4486,0,0,0.184,0.61,,10.0 0,36.3456,2023,10,30,181.0940,50.3617,5.9495,0.22600,39.31834,30.43226,7.60,5.0,0.15 4791.260,107.9627,1.7380,87,19.7461,Known errors,-1.00,-1,-1,-1 20231031_244166,59745.22 ------ occelmnt file for Occult END ----------------------------------- ============================================ Calculator (s): Steve Preston Date of update: 2022 Jun 15, 05:13 UT Steve Preston 7640 NE 32nd St Medina, WA 98039 stevepr@acm.org