Orbital stability analysis and photometric characterization of the second Earth Trojan asteroid 2020 XL<sub>5</sub>.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 35105878.
- Also identified by DOI 10.1038/s41467-022-27988-4 and PMC identifier 8807697.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Trojan asteroids are small bodies orbiting around the L<sub>4</sub> or L<sub>5</sub> 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 TK<sub>7</sub> has been the only known Earth Trojan thus far. Here we confirm that the recently discovered 2020 XL<sub>5</sub> 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 XL<sub>5</sub> will remain in L<sub>4</sub> for at least 4 000 years. With a photometric analysis we estimate its absolute magnitude to be [Formula: see text], 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.