(505657) 2014 SR339

Asteroid of the Apollo group March 2018 yes (505657) 2014 SR 339 #FFC2E0 2014 SR339 Arecibo-animated.gif Radar images of 2014 SR 339 taken by the Arecibo Observatory on 9 February 2018 WISE Earth orbit 30 September 2014 (505657) 2014 SR 339 ApolloNEOPHA 23 March 2018 (JD 2458200.5) 0 3.41 yr (1,245 d) 1.6948 AU 0.9046 AU 1.2997 AU 0.3040 1.48 yr (541 d) 60.524° 0.6652 ms / day 29.790° 138.78° 299.60° 0.0354 AU LD on on 3 (>1.5 km × ? km) 0.971 0.367 km 8 - 9 h8.729 hlightcurve-plot-Warner 0.068 0.074 C(assumed on albedo) 18.6 (505657) 2014 SR 339 is a dark and elongated asteroid, classified as a near-Earth object and potentially hazardous asteroid of the Apollo group, approximately 970 m ft off 2 us in diameter. It was discovered on 30 September 2014, by NASA's Wide-field Infrared Survey Explorer telescope (WISE) in Earth's orbit. Closely observed at Goldstone and Arecibo in February 2018, it has a rotation period of 8.7 hours. Orbit and classification 2014 SR 339 is a member of the Apollo asteroids, which cross the orbit of Earth. Apollo's are the largest group of near-Earth objects with nearly 10 thousand known objects. It orbits the Sun at a distance of 0.90–1.70 AU once every 18 months (541 days; semi-major axis of 1.30 AU). Its orbit has an eccentricity of 0.30 and an inclination of 30° with respect to the ecliptic. With an aphelion of 1.70 AU, it is also a Mars-crosser, as it crosses the orbit of the Red Planet at 1.666 AU. The body's observation arc begins with its official discovery observation by WISE in September 2014. Close approaches As a potentially hazardous asteroid, 2014 SR 339 has a minimum orbital intersection distance (MOID) with Earth of less than 0.05 AU and a diameter of greater than 150 meters. The Earth-MOID is currently 0.0354 AU km on off 3, which translates into 13.8 lunar distances (LD). 2018 flyby On 7 February 2018 it passed 0.054 AU LD on on 2 from the Earth when its apparent magnitude brightened to 14. Goldstone observed it until the following day. While this was an 8.1-million kilometer flyby, the next close flyby of 6.3 million km will occur on 5 February 2058, and another 7.6 million km on 8 February 2095. It will also have a 3.2 million km flyby of Mars on 26 September 2048. Physical characteristics The asteroid's spectral type is unknown. Due to its unusually low albedo (see below) it is likely a carbonaceous C-type asteroid. Rotation period On 9 February, radiometric observations by the Arecibo Observatory revealed that the asteroid has an elongated, lumpy shape. The radar images also gave it a rotational period between 8 and 9 hours. A refined period of 8.7 hour agrees with (photometric) lightcurve observations by American photometrist Brian Warner at the Center for Solar System Studies (U82) during 9–11 February 2018, who obtained a period of 8.729 hours with a high brightness amplitude of 0.93 magnitude, which also indicates a non-spheroidal shape (U=3-).lightcurve-plot-Warner Diameter and albedo According to the survey carried out by the NEOWISE mission of NASA's WISE telescope, 2014 SR 339 measures 0.971 kilometers in diameter and its surface has an albedo of 0.068. During its close approach in February 2018, radiometric observations by Arecibo Observatory determined that the object is at least 1.5 km mi off us wide. Data from the Arecibo Telescope released in 2022 showed an unusually high radar albedo, possibly indicating rich metal content.Sky & Telescope ARECIBO LEGACY: NEW DATA ON NEAR-EARTH ASTEROIDS Colin Stuart November 1, 2022 https://skyandtelescope.org/astronomy-news/arecibos-legacy-new-data-on-near-earth-asteroid/ Numbering and naming This minor planet was numbered by the Minor Planet Center on 4 November 2017 (M.P.C. 107069). As of 2018, it has not been named. Gallery Notes lightcurve-plot-Warner lightcurve plot of (505657) 2014 SR339: rotation period 8.729 0.002 hours with a brightness amplitude of 0.93 mag. Quality code of 3-. Summary figures at the Center for Solar System Studies (CS3) References 2018-02-26 last obs. JPL Small-Body Database Browser: 505657 (2014 SR339) https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2505657 Jet Propulsion Laboratory 5 March 2018 505657 (2014 SR339) Minor Planet Center https://www.minorplanetcenter.net/db_search/show_object?object_id=505657 5 March 2018 MPC/MPO/MPS Archive Minor Planet Center https://www.minorplanetcenter.net/iau/ECS/MPCArchive/MPCArchive_TBL.html 5 March 2018 6 C. R. Nugent A. Mainzer J. Masiero J. Bauer R. M. Cutri T. Grav E. Kramer S. Sonnett R. Stevenson E. L. Wright December 2015 NEOWISE Reactivation Mission Year One: Preliminary Asteroid Diameters and Albedos The Astrophysical Journal 814 2 13 2015ApJ...814..117N 10.1088/0004-637X/814/2/117 1509.02522 9341381 Goldstone Radar Observations Planning: Asteroids 2002 AJ129, 2014 SR339, 2015 BN509, and 2018 CB https://echo.jpl.nasa.gov/asteroids/2002AJ129/2002AJ129_planning.2018.html Lance Benner – NASA/JPL 5 March 2018 Recent radar images of near-Earth asteroid (505657) 2014 SR339 from @NAICobservatory show a lumpy, elongated body at least 1.5 km long and rotating once every 8 to 9 hours! Recent radar images of (505657) 2014 SR339 https://twitter.com/AreciboRadar/status/963448575312228352 Twitter 5 March 2018 Asteroid 505657 2014 SR339 https://www.asteroidsnear.com/asteroid-505657-2014-sr339-4429 asteroidsnear.com 5 March 2018 14 February 2018 https://web.archive.org/web/20180214142435/https://www.asteroidsnear.com/asteroid-505657-2014-sr339-4429 dead Near-Earth asteroid (505657) 2014 SR339 http://outreach.naic.edu/ao/blog/near-earth-asteroid-505657-2014-sr339 14 February 2018 Arecibo Observatory – NASA/JPL 5 March 2018 External links List of the Potentially Hazardous Asteroids (PHAs), Minor Planet Center List Of Apollo Minor Planets (by designation), Minor Planet Asteroid Lightcurve Database (LCDB), query form (info https://web.archive.org/web/20171216050541/http://www.minorplanet.info/lightcurvedatabase.html 16 December 2017 ) 505657 505657 2014SR339 2505657 505657 (505657) 2014 SR 339 505657 505657 505657 Category:Near-Earth objects in 2018 20140930