12923 Zephyr

Stony asteroid October 2019 yes 12923 Zephyr #FFC2E0 LONEOS Anderson Mesa Stn. 11 April 1999 (12923) Zephyr 1999 GK 4 ' z ɛ f ərzephyr Zephyrus(Greek mythology) NEO Apollo PHA 4 September 2017 (JD 2458000.5) 0 61.75 yr (22,554 days) 21 April 1955 2.9267 AU 0.9964 AU 1.9615 AU 0.4920 2.75 yr (1,003 days) 199.23° 0.3588 ms / day 5.3045° 168.21° 147.06° 0.0211 AU (8.2 LD) 1.86 0.46 km 2.060 0.013 km 2.062 km 3.891 hLCDB-Pravec-1999 0.1764 0.199 0.034 0.20 0.16 0.21 0.17 SMASS S: S 15.40 0.1 (R)LCDB-Pravec-1999 15.77 0.24 15.8 15.93 0.078 12923 Zephyr (prov. designation: 1999 GK 4) is a stony asteroid, classified as potentially hazardous asteroid and near-Earth object of the Apollo group, approximately 2 km mi off 2 us in diameter. It was discovered on 11 April 1999, by astronomers of the Lowell Observatory Near-Earth Object Search at Anderson Mesa Station near Flagstaff, Arizona. The asteroid was named after the deity Zephyrus from Greek mythology. Orbit and classification Zephyr orbits the Sun at a distance of 1.0–2.9 AU once every 2 years and 9 months (1,003 days). Its orbit has an eccentricity of 0.49 and an inclination of 5° with respect to the ecliptic. The body's observation arc begins with a precovery taken at Palomar Observatory in April 1955, almost 44 years prior to its official discovery observation at Anderson Mesa. Close encounters This near-Earth asteroid has an Earth minimum orbital intersection distance of 0.0211 AU km on off 3, which corresponds to 8.2 lunar distances. This short distance as well as its sufficiently large size makes it a potentially hazardous asteroid. In September 2010, the asteroid approached Earth at 0.2546 AU km on off 3; it will make close encounters with Earth again in 2021, 2032 and 2043. Naming This minor planet was named after the god of the west wind, Zephyrus, from Greek mythology. The name was suggested by M. Smitherman. The official naming citation was published by the Minor Planet Center on 28 September 2004 (M.P.C. 52768). Physical characteristics In the SMASS classification, Zephyr is a common S-type asteroid. The body is also characterized as a stony asteroid by the Infrared Telescope Facility, and in the Tholen classification (noisy spectrum). Rotation period In April 1999, a rotational lightcurve of Zephyr was obtained from photometric observations by Czech astronomer Petr Pravec at Ondřejov Observatory. Lightcurve analysis gave a well-defined rotation period of 3.891 hours with a brightness amplitude of 0.18 magnitude (U=3).LCDB-Pravec-1999 Diameter and albedo According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer and the ExploreNEOs survey of the Spitzer Space Telescope, Zephyr measures between 1.86 and 2.062 kilometers in diameter and its surface has an albedo between 0.1764 and 0.21. The Collaborative Asteroid Lightcurve Link adopts Petr Pravec's revised WISE data, with albedo of 0.1764 and a diameter of 2.06 kilometers based on an absolute magnitude of 15.93. Notes LCDB-Pravec-1999 Pravec (1999) web: rotation period 3.891 hours with a brightness amplitude of 0.18 mag. Summary figures for (12923) Zephyr at LCDB and Ondrejov Asteroid Photometry Project (data sheet) References 30em 2017-01-19 last obs. JPL Small-Body Database Browser: 12923 Zephyr (1999 GK4) https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2012923 Jet Propulsion Laboratory 17 October 2017 Dictionary of Minor Planet Names – (12923) Zephyr, Addendum to Fifth Edition: 2003–2005 Schmadel Lutz D. Springer Berlin Heidelberg 76 2006 978-3-540-34361-5 10.1007/978-3-540-34361-5_734 (12923) Zephyr [1.96, 0.49, 5.3] 12923 Zephyr (1999 GK4) Minor Planet Center https://www.minorplanetcenter.net/db_search/show_object?object_id=12923 17 October 2017 MPC/MPO/MPS Archive Minor Planet Center https://www.minorplanetcenter.net/iau/ECS/MPCArchive/MPCArchive_TBL.html 17 October 2017 6 A. Mainzer T. Grav J. Bauer J. Masiero R. S. McMillan R. M. Cutri R. Walker E. Wright P. Eisenhardt D. J. Tholen T. Spahr R. Jedicke L. Denneau E. DeBaun D. Elsbury T. Gautier S. Gomillion E. Hand W. Mo J. Watkins A. Wilkins G. L. Bryngelson A. Del Pino Molina S. Desai M. Gómez Camus S. L. Hidalgo I. Konstantopoulos J. A. Larsen C. Maleszewski M. A. Malkan J.-C. Mauduit B. L. Mullan E. W. Olszewski J. Pforr A. Saro J. V. Scotti L. H. Wasserman December 2011 NEOWISE Observations of Near-Earth Objects: Preliminary Results The Astrophysical Journal 743 2 17 2011ApJ...743..156M 10.1088/0004-637X/743/2/156 1109.6400 12923 17 October 2017 6 A. W. Harris M. Mommert J. L. Hora M. Mueller D. E. Trilling B. Bhattacharya W. F. Bottke S. Chesley M. Delbo J. P. Emery G. Fazio A. Mainzer B. Penprase H. A. Smith T. B. Spahr J. A. Stansberry C. A. Thomas March 2011 ExploreNEOs. II. The Accuracy of the Warm Spitzer Near-Earth Object Survey The Astronomical Journal 141 3 10 2011AJ....141...75H 10.1088/0004-6256/141/3/75 https://authors.library.caltech.edu/22857/1/Harris2011p13012Astron_J.pdf Petr Pravec Alan W. Harris Peter Kusnirák Adrián Galád Kamil Hornoch September 2012 Absolute magnitudes of asteroids and a revision of asteroid albedo estimates from WISE thermal observations Icarus 221 1 365–387 2012Icar..221..365P 10.1016/j.icarus.2012.07.026 6 A. Mainzer T. Grav J. Masiero E. Hand J. Bauer D. Tholen R. S. McMillan T. Spahr R. M. Cutri E. Wright J. Watkins W. Mo C. Maleszewski November 2011 NEOWISE Studies of Spectrophotometrically Classified Asteroids: Preliminary Results The Astrophysical Journal 741 2 25 2011ApJ...741...90M 10.1088/0004-637X/741/2/90 1109.6407 6 C. A. Thomas D. E. Trilling J. P. Emery M. Mueller J. L. Hora L. A. M. Benner B. Bhattacharya W. F. Bottke S. Chesley M. Delbó G. Fazio A. W. Harris A. Mainzer M. Mommert A. Morbidelli B. Penprase H. A. Smith T. B. Spahr J. A. Stansberry September 2011 ExploreNEOs. V. Average Albedo by Taxonomic Complex in the Near-Earth Asteroid Population The Astronomical Journal 142 3 12 2011AJ....142...85T 10.1088/0004-6256/142/3/85 free Cristina A. Thomas Joshua P. Emery David E. Trilling Marco Delbó Joseph L. Hora Michael Mueller January 2014 Physical characterization of Warm Spitzer-observed near-Earth objects Icarus 228 217–246 2014Icar..228..217T 10.1016/j.icarus.2013.10.004 1310.2000 6 Peter Veres Robert Jedicke Alan Fitzsimmons Larry Denneau Mikael Granvik Bryce Bolin Serge Chastel Richard J. Wainscoat William S. Burgett Kenneth C. Chambers Heather Flewelling Nick Kaiser Eugen A. Magnier Jeff S. Morgan Paul A. Price John L. Tonry Christopher Waters November 2015 Absolute magnitudes and slope parameters for 250,000 asteroids observed by Pan-STARRS PS1 Preliminary results Icarus 261 34–47 2015Icar..261...34V 10.1016/j.icarus.2015.08.007 1506.00762 External links (12923) Zephyr at NEODyS-2 Asteroid Lightcurve Database (LCDB), query form (info https://web.archive.org/web/20171216050541/http://www.minorplanet.info/lightcurvedatabase.html 16 December 2017 ) Dictionary of Minor Planet Names, Google books Asteroids and comets rotation curves, CdR Observatoire de Genève, Raoul Behrend 12923 12923 Zephyr (12922) 1998 WW19 12923 012923 012923 Category:Named minor planets Category:Earth-crossing asteroids 012923 19990411