(614689) 2020 XL5

Near-Earth Asteroid February 2021 yes (614689) 2020 XL 5 #FFC2E0 2020 XL5 Lowell Discovery.jpg 2020 XL 5 imaged by the Lowell Discovery Telescope on 2 February 2021 Pan-STARRS 1 Haleakala Obs. 12 December 2020 (614689) 2020 XL 5 P11aRcq Earth trojanNEOApollo 21 January 2022 (JD 2459600.5) 0 8.88 yr (3,243 days) 23 December 2012 1.388 AU 0.6133 AU 1.001 AU 0.38713 1.00 yr (365.7 d) 316.420° 0.9845193 ms / day 13.847° 153.598° 87.981° 0.07571 AU km 0.02726 AU km 1.18 0.08 km 0.06 0.03 C 20–23 18.58 0.16 0.15 (r-band) (614689) 2020 XL 5 is a near-Earth asteroid and Earth trojan discovered by the Pan-STARRS 1 survey at Haleakala Observatory, Hawaii on 12 December 2020. It oscillates around the Sun–Earth Lagrangian point (leading 60°), one of the dynamically stable locations where the combined gravitational force acts through the Sun's and Earth's barycenter. Analysis of 2020 XL 5's trojan orbit stability suggests it will remain around Earth's yes point for at least four thousand years until gravitational perturbations from repeated close encounters with Venus destabilize its trojan configuration. With a diameter of about 1.2 km mi, 2020 XL 5 is the second Earth trojan discovered, after 706765 2010 TK 7Chang Kenneth Astronomers Find a New Asteroid Sharing Earth's Orbit The Trojan asteroid 2020 XL5, which follows the same path around the sun as our planet, was revealed only after a decade of searching. https://nytimes.com/2022/02/02/science/astronomy-asteroid-trojan.html 2022-02-02 The New York Times 2022-02-02 (about 300 m ft in diameter), and is the largest of its kind known. Discovery 2020 XL 5 was discovered by the Pan-STARRS 1 survey at Haleakala Observatory, Hawaii on 12 December 2020. It was first observed in the constellation Crater at an apparent magnitude of 21.4. The asteroid was moving at an on-sky rate of 3.02 arcseconds per minute, from a distance of 0.68 AU e6km e6mi unit from Earth. The asteroid was subsequently listed on the Minor Planet Center's Near-Earth Object Confirmation Page (NEOCP) as P11aRcq. Over two days, follow-up observations were carried out by the Višnjan Observatory (L01), ESA Optical Ground Station (J04), and Cerro Tololo Observatory (807). The asteroid was identified in earlier Mount Lemmon Survey (G96) observations from 26 November 2020. The listing was confirmed and publicly announced as 2020 XL 5 on 14 December 2020. Name and numbering This minor planet was given the permanent number 614689 by the Minor Planet Center on 28 March 2022 and is now eligible for naming. In accordance with the International Astronomical Union's naming conventions for near-Earth objects, 2020 XL 5 will be given a mythological name. Orbit and classification thumb|left|Heliocentric orbit diagram of 2020 XL 5 along with the inner planets The orbit of 2020 XL 5 is well known with an uncertainty parameter of 0 and a long observation arc over 8 years. The asteroid has been identified in several precovery observations by various sky surveys, including Pan-STARRS, from dates as far back as December 2012. 2020 XL 5 orbits the Sun at an average distance of 1.001 AU once every 365.8 days, or approximately 1 Earth year. Its orbit has a high eccentricity of 0.388 and an inclination of 13.8° with respect to the ecliptic plane. Over the course of its orbit, its distance from the Sun ranges from 0.61 AU at perihelion to 1.39 AU at aphelion, crossing the orbits of Venus and Earth. Since its orbit crosses Earth's while having a semi-major axis greater than 1 AU (by a small margin), 2020 XL 5 is classified as an Apollo asteroid. Trojan orbit thumb|left|Effective potential plot showing Earth's Lagrangian points (not to scale); contours around yes and yes represent tadpole loop paths thumb|left|Animation of 2020 XL 5's orbit from 1600 to 2500 - relative to Sun and Earth Yellow Sun RoyalBlue EarthMagenta 2020 XL 5 Trojan objects are most easily conceived as orbiting at a Lagrangian point, a dynamically stable location (where the combined gravitational force acts through the Sun's and Earth's barycenter) 60 degrees ahead of () or behind () a massive orbiting body, in a type of 1:1 orbital resonance. In reality, they oscillate around such a point. On 26 January 2021, amateur astronomer Tony Dunn reported that 2020 XL 5's nominal trajectory appears to be librating about Earth's leading yes Lagrangian point, suspecting it to be an Earth trojan. Subsequent analysis confirmed modeling stability for at least several thousand years into the future based on existing orbital parameters. This would make 2020 XL 5 more stable than the prototype yes Earth trojan 2010 TK 7, which is potentially unstable on timescales of less than 2,000 years. Additional follow-up observations and precoveries confirmed 2020 XL 5's trojan nature, and showed that it will leave trojan orbit at least 4,000 years into the future. Numerical simulations indicate that 2020 XL 5 has likely been captured into the yes Langrangian point since the 15th century. 2020 XL 5's high orbital eccentricity results in wide, tadpole-shaped oscillation paths in a corotating reference frame with Earth and its Lagrangian points. Although the asteroid crosses Venus's orbit with a minimum orbit intersection distance (MOID) of 0.0273 AU e6km e6mi unit 2, perturbations by the planet are currently negligible since its nominal orbit brings it either too high or too low from the plane of Venus's orbit. Venus's influence on 2020 XL 5's orbit will become greater over time as their longitudes of the ascending node precess over hundreds of years, lowering 2020 XL 5's Venus MOID and eventually destabilizing its trojan orbit by sending it past Earth's point in several thousand years. Physical characteristics Photometric measurements of optical observations from 2020–2021 show that 2020 XL 5 exhibits a color resembling that of carbonaceous C-type asteroids. Based on 2020 XL 5's phase curve being similar to C-type asteroids, its absolute magnitude (H) of 18.6 corresponds to a mean diameter about 1.18 km mi, calculated from a geometric albedo of 0.06 typical for C-type asteroids. This makes 2020 XL 5 the largest Earth trojan asteroid known to date, being up to three times as large as (706765) 2010 TK 7 whose size is 0.3 km mi. Because of its fixed position in Earth's sky, relative to the Sun, 2020 XL 5 is only visible low on the horizon, during twilight. Accurate photometry of its light curve by terrestrial observers is made erratic by heavy atmospheric distortion and swamped by scattered light from the recently set Sun. Consequently, no information about its rotation has been determined. Exploration Due to 2020 XL 5's high orbital inclination, a rendezvous mission to the asteroid from low Earth orbit (LEO) would require a minimum total delta-v of 10.3 km/s mi/s – too high to be considered an ideal target for a low-energy trajectory. On the other hand, a flyby trajectory to 2020 XL 5 from LEO could be more feasible with a minimum total delta-v of 3.3 km/s mi/s. See also Co-orbital configuration Claimed moons of Earth Horseshoe orbit Quasi-satellite References 2021-11-09 last obs. JPL Small-Body Database Browser: 2020 XL5 https://ssd.jpl.nasa.gov/tools/sbdb_lookup.html#/?sstr=2614689 Jet Propulsion Laboratory 5 February 2021 (614689) = 2020 XL5 http://www.minorplanetcenter.net/db_search/show_object?object_id=614689 Minor Planet Center International Astronomical Union 5 February 2021 Ephemerides at discovery (obs. code F51) 2020XL5 Ephemerides https://newton.spacedys.com/neodys/index.php?pc=1.1.3.1&n=2020XL5&oc=F51&y0=2020&m0=12&d0=12&h0=14&mi0=49&y1=2020&m1=12&d1=12&h1=15&mi1=24&ti=1&tiu=minutes Near Earth Objects – Dynamic Site Department of Mathematics, University of Pisa, Italy 6 February 2021 2020 XL5 https://neoexchange.lco.global/target/63044/ NEO Exchange Las Cumbres Observatory 14 December 2020 6 February 2021 "Pseudo-MPEC" for P11aRcq https://projectpluto.com/neocp2/mpecs/P11aRcq.htm Bill Gray Project Pluto 14 December 2020 6 February 2021 5 February 2022 https://web.archive.org/web/20220205101629/https://projectpluto.com/neocp2/mpecs/P11aRcq.htm dead MPEC 2020-X171 : 2020 XL5 https://minorplanetcenter.net/mpec/K20/K20XH1.html Minor Planet Electronic Circular Minor Planet Center 14 December 2020 5 February 2021 Re: Could newly-discovered 2020 XL5 be an Earth Trojan? https://groups.io/g/mpml/message/36164 Aldo Vitagliano groups.io 28 January 2021 6 February 2021 Re: Could newly-discovered 2020 XL5 be an Earth Trojan? https://groups.io/g/mpml/message/36217 Tony Dunn groups.io 2 January 2021 6 February 2021 Second Earth Trojan Discovered https://skyandtelescope.org/astronomy-news/second-earth-trojan-asteroid-discovered/ Jeff Hecht Sky & Telescope 4 February 2021 5 February 2021 Martin Connors Paul Wiegert Christian Veillet Earth's Trojan asteroid Nature July 2011 475 7357 481–483 10.1038/nature10233 2011Natur.475..481C 21796207 205225571 Carlos de la Fuente Marcos Raúl de la Fuente Marcos Transient Terrestrial Trojans: Comparative Short-term Dynamical Evolution of 2010 TK7 and 2020 XL5 Research Notes of the American Astronomical Society 18 February 2021 5 2 29 free 10.3847/2515-5172/abe6ad 2021RNAAS...5...29D Man-To Hui Paul A. Wiegert David J. Tholen Dora Föhring The Second Earth Trojan 2020 XL5 The Astrophysical Journal Letters November 2021 922 2 L25 10.3847/2041-8213/ac37bf 2111.05058 2021ApJ...922L..25H 243860678 free etal T. Santana-Ros M. Micheli L. Faggioli R. Cennamo M. Devogèle A. Alvarez-Candal Orbital stability analysis and photometric characterization of the second Earth Trojan asteroid 2020 XL5 https://www.nature.com/articles/s41467-022-27988-4.pdf Nature Communications February 2022 13 447 L25 10.1038/s41467-022-27988-4 free 35105878 8807697 2022NatCo..13..447S M.P.C. 139917 https://minorplanetcenter.net/iau/ECS/MPCArchive/2022/MPC_20220328.pdf Minor Planet Circular Minor Planet Center 1529 28 March 2022 14 April 2022 Rules and Guidelines for Naming Non-Cometary Small Solar-System Bodies https://www.wgsbn-iau.org/documentation/NamesAndCitations.pdf IAU WG Small Body Nomenclature International Astronomical Union 8 20 December 2021 14 April 2022 External links Data from NSF's NOIRLab Show Earth Trojan Asteroid Is the Largest Found, NOIRLab, 1 February 2022 Second Earth Trojan Discovered, Jeff Hecht, Sky & Telescope, 4 February 2021 2020xl5 2020XL5 2614689 collapsed 614689 (614689) 2020 XL 5 Astronomy Outer Space 614689 614689 614689 614689 614689 20201212 20201212