Orbital stability analysis and photometric characterization of the second Earth Trojan asteroid 2020 XL5

Journal Article · 01 February 2022 · Nature Communications

DOI: https://doi.org/10.1038/s41467-022-27988-4 · OSTI ID:2470941

Santana-Ros, T.  ^[1]; Micheli, M.  ^[2]; Faggioli, L.  ^[2]; Cennamo, R.  ^[2]; Devogèle, M.  ^[3]; Alvarez-Candal, A.  ^[4]; Oszkiewicz, D.  ^[5]; Ramírez, O. ^[6]; Liu, P. -Y. ^[7]; Benavidez, P. G.  ^[7]; Campo Bagatin, A.  ^[7]; Christensen, E. J. ^[8]; Wainscoat, R. J.  ^[9]; Weryk, R.  ^[10]; Fraga, L.  ^[11]; Briceño, C.  ^[12]; Conversi, L.  ^[13]

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1. Universidad de Alicante (Spain); Universitat de Barcelona (IEEC-UB) (Spain). Institut de Ciències del Cosmos (ICCUB)
2. ESA Near-Earth Object Coordination Centre (NEOCC), Frascati (Italy)
3. University of Central Florida, Orlando, FL (United States)
4. Consejo Superior de Investigaciones Cientificas (CSIC), Granada (Spain). Instituto de Astrofísica de Andalucía (IAA); Universidad de Alicante (Spain); Ministério da Ciência, Tecnologia e Inovações (MCTI), Rio de Janeiro (Brazil). Observatório Nacional (ON)
5. Adam Mickiewicz University, Poznan (Poland)
6. Solenix Deutschland GmbH, Darmstadt (Germany)
7. Universidad de Alicante (Spain)
8. University of Arizona, Tucson, AZ (United States)
9. University of Hawaii, Honolulu, HI (United States)
10. University of Western Ontario, London, ON (Canada)
11. Ministério da Ciência, Tecnologia e Inovações (MCTI), Itajubá (Brazil). Laboratório Nacional de Astrofísica (LNA)
12. Cerro Tololo Inter-American Observatory (CTIO), La Serena (Chile); National Optical-Infrared Astronomy Research Laboratory (NOIRLab), La Serana (Chile)
13. ESA Near-Earth Object Coordination Centre (NEOCC), Frascati (Italy); ESA ESRIN, Frascati (Italy)

Trojan asteroids are small bodies orbiting around the L₄ or L₅ Lagrangian points of a Sun-planet system. Due to their peculiar orbits, they provide key constraints to the Solar System evolution models. Despite numerous dedicated observational efforts in the last decade, asteroid 2010 TK₇ has been the only known Earth Trojan thus far. Here we confirm that the recently discovered 2020 XL₅ is the second transient Earth Trojan known. To study its orbit, we used archival data from 2012 to 2019 and observed the object in 2021 from three ground-based observatories. Our study of its orbital stability shows that 2020 XL₅ will remain in L₄ for at least 4 000 years. With a photometric analysis we estimate its absolute magnitude to be $${H}_{r}=18.5{8}_{-0.15}^{+0.16}$$, and color indices suggestive of a C-complex taxonomy. Assuming an albedo of 0.06 ± 0.03, we obtain a diameter of 1.18 ± 0.08 km, larger than the first known Earth Trojan asteroid.

• Research Organization: Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: European Union (EU); Generalitat Valenciana; Institute of Cosmos Sciences (ICCUB); Ministry of Science, Innovation and Universities (MICIU); National Aeronautics and Space Administration (NASA); National Science Centre (NCN); National Science Foundation (NSF); USDOE
• Grant/Contract Number: AC02-05CH11231
• OSTI ID: 2470941
• Journal Information: Nature Communications, Journal Name: Nature Communications Journal Issue: 1 Vol. 13; ISSN 2041-1723
• Publisher: Nature Publishing GroupCopyright Statement
• Country of Publication: United States
• Language: English