1685 Toro

Near-Earth asteroid March 2020 yes 1685 Toro #FFC2E0 001685-asteroid shape model (1685) Toro.png Shape model of Toro from its lightcurve 17 July 1948 C. A. Wirtanen Lick Obs. (1685) Toro 1948 OA Betulia Toro Herrick(wife Samuel Herrick) NEOApolloMars-crosser 5 May 2025 (JD 2460800.5) 0 76.75 yr (28,032 days) 1.9643 AU 0.7714 AU 1.3679 AU 0.4360 1.60 yr (584 days) 319.462° 9.382° 274.208° 127.279° 0.0510 AU19.9 LD 3.810 0.049 km4.1 km3.5 +0.3 -0.4 km 10.185 0.003 h10.1862 0.0006 h10.191 0.005 h10.195 h10.19540 h10.196 h10.199 0.003 h10.1995 0.0004 h10.203 0.003 h10.197826 0.000002 h -69° 75° 0.247 0.0490.290.38 0.33 S (Tholen) S (SMASS) S B–V 0.880 U–B 0.470 13.9014.02 1.1114.2814.23 1685 Toro (prov. designation: 1948 OA) is an asteroid and near-Earth object of the Apollo group on an eccentric orbit. It was discovered on 17 July 1948, by American astronomer Carl Wirtanen at Lick Observatory on Mount Hamilton, California. The stony S-type asteroid has a rotation period of 10.2 hours and measures approximately 4 km mi off 2 us in diameter. It is named for Betulia Toro Herrick, wife of astronomer Samuel Herrick. Classification and orbit Toro is an Apollo asteroid, a subgroup of near-Earth asteroids that cross the orbit of Earth. It orbits the Sun at a distance of 0.8–2.0 AU once every 584 days. Its orbit has an eccentricity of 0.44 and an inclination of 9° with respect to the ecliptic. This asteroid's orbit also shows a 5:8 resonance with Earth and a near 5:13 resonance with Venus. This near resonance results from Earth and Venus being in a near 8:13 resonance with each other. It was the third Apollo asteroid to be discovered. The current resonance with Earth will last for only a few thousand years. Calculations show that Toro will leave it in 2960 CE, and that it will enter the region of 5:13 resonance with Venus in 3470 CE. This is because the distance from Earth's orbit will become larger and that from Venus's orbit smaller. A study of long-term stability shows that the alternating resonances will possibly be broken roughly 3 million years from now because of close approaches between Toro and Mars.August 2025 The source for this is an article from 1973, at which time Toro's orbit was not known with good precision, and the accuracy of orbit simulations was limited. Toros Earth minimum orbit intersection distance of 0.051 AU km on off 3, is just above the 0.05 AU requirement to be listed as a potentially hazardous asteroid. With an orbital uncertainty U = 0, its orbit and future close approaches are well determined. Toro's orbit may be similar to that of the Sylacauga meteorite, the first meteorite authenticated to have struck a human. Naming This minor planet was named after the maiden name of Betulia (née Toro) Herrick, wife of American astronomer Samuel Herrick. Herrick had studied the asteroid's orbit, and requested the name, along with the other asteroid, 1580 Betulia. The official 1685 naming citation was published by the Minor Planet Center on 10 March 1966 (M.P.C. 2504). Physical characteristics In the Tholen and SMASS taxonomic scheme, Toro is characterized as a stony S-type asteroid. It is reported to be composed of L chondrite with a high albedo in the range of 0.24–0.34. It has an extremely well-measured rotation period of 10.2 hours. Its rotation period is slowly increasing due to the YORP effect. References 2025-04-16 last obs. JPL Small-Body Database Browser: 1685 Toro (1948 OA) https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2001685 Jet Propulsion Laboratory 18 August 2025 Dictionary of Minor Planet Names https://archive.org/details/dictionaryminorp00schm limited Schmadel Lutz D. 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January 2013 Asteroid Lightcurve Analysis at the Palmer Divide Observatory: 2012 June - September Minor Planet Bulletin http://www.minorplanet.info/MPB/issues/MPB_40-1.pdf 40 1 26–29 2013MPBu...40...26W 1052-8091 17 March 2020 23 February 2020 https://web.archive.org/web/20200223220337/http://www.minorplanet.info/MPB/issues/MPB_40-1.pdf dead Warner Brian D. July 2016 Near-Earth Asteroid Lightcurve Analysis at CS3-Palmer Divide Station: 2016 January–April Minor Planet Bulletin http://www.minorplanet.info/MPB/issues/MPB_43-3.pdf 43 3 240–250 2016MPBu...43..240W 1052-8091 17 March 2020 27 July 2021 https://web.archive.org/web/20210727032747/http://www.minorplanet.info/MPB/issues/MPB_43-3.pdf dead 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 53493339 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 L. Danielsson W.-H. Ip May 1972 Capture Resonance of the Asteroid 1685 Toro by the Earth Science 176 4037 906–907 1972Sci...176..906D 10.1126/science.176.4037.906 17829299 45175037 Dictionary of Minor Planet Names https://archive.org/details/dictionaryminorp00schm limited Schmadel Lutz D. Springer Berlin Heidelberg (1580) Betulia 125 2007 978-3-540-00238-3 10.1007/978-3-540-29925-7_1581 Samuel Herrick, Engineering; Astronomy: Los Angeles Calisphere – University of California http://content.cdlib.org/view?docId=hb9k4009c7;NAAN=13030&doc.view=frames&chunk.id=div00024&toc.depth=1&toc.id=&brand=calisphere 22 December 2016 Science in Review: Research Work in Astronomy and Cancer Lead Year's List of Scientific Developments Waldemar Kaempffert The New York Times 26 December 1948 87 0362-4331 http://select.nytimes.com/gst/abstract.html?res=F00F1EFE3F5E167B93C4AB1789D95F4C8485F9 4 August 2011 J. G. Williams G. W. Wertherill August 1973 Minor planets and related objects. XIII. Long-term orbital evolution of (1685) Toro Astronomical Journal 78 510 1973AJ.....78..510W 10.1086/111451 free Povenmire, H. March 1995 The Sylacauga, Alabama Meteorite: The Impact Locations, Atmosphere Trajectory, Strewn Field and Radiant Abstracts of the Lunar and Planetary Science Conference 26 1133 1995LPI....26.1133P 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 119278697 Hartmann, W. K. (2005). Moons & Planets (5th ed.). Belmont, Calif.: Brooks/Cole. 0534493939 10.1051/0004-6361/202141844 Rotation acceleration of asteroids (10115) 1992 SK, (1685) Toro, and (1620) Geographos due to the YORP effect 2022 Ďurech J. Vokrouhlický D. Pravec P. Krugly Yu. N. Kim M.-J. Polishook D. Ayvazian V. V. Bonev T. Choi Y.-J. Datashvili D. G. Donchev Z. Ehgamberdiev S. A. Hornoch K. Inasaridze R. Ya. Kapanadze G. V. Kim D.-H. Kučáková H. Kusakin A. V. Kušnirák P. Lee H.-J. Molotov I. E. Moon H.-K. Mykhailova S. S. Nikolenko I. V. Novichonok A. Oey J. Omarov Ch. T. Pollock J. T. Reva I. V. Rumyantsev V. V. Astronomy & Astrophysics 657 A5 2110.06548 2022A&A...657A...5D 238744034 1 External links Lightcurve plot of 1685 Toro, Palmer Divide Observatory, B. D. Warner (2012) Lightcurve Database Query (LCDB), at www.minorplanet.info Dictionary of Minor Planet Names, Google books 1685 1685 Toro 1684 Iguassú 1685 1686 De Sitter 001685 Category:Discoveries by Carl A. Wirtanen Category:Named minor planets 001685 001685 19480717