2020 PP₁

2020 PP₁ is a sub-kilometer asteroid, classified as a near-Earth object of the Apollo group, that is a temporary quasi-satellite of the Earth. There are over a dozen known Earth quasi-satellites, some of which switch periodically between the quasi-satellite and horseshoe co-orbital states.^[6]

2020 PP₁ was discovered on 12 August 2020 by the Pan-STARRS 1 survey at the Haleakalā Observatory.^[1] It was later recovered by the Karl Schwarzschild Observatory in August 2021, which allowed for precovery in earlier Pan-STARRS observations from 24 July 2017.^[7]

2020 PP₁ is currently an Apollo asteroid (Earth-crossing but with a period longer than a year). Its semi-major axis (currently 1.001715 AU) is similar to that of Earth (0.999789 AU), but it has both low eccentricity (0.07384) and low orbital inclination (5.827°). It alternates between being an Aten asteroid and being an Apollo asteroid, although its orbital evolution is not fully stable and it can be considered as a temporary quasi-satellite of the Earth; its orbital evolution is akin to that of 469219 Kamoʻoalewa.^[6]

With an absolute magnitude of 26.6, it has a diameter in the range 10–30 meters (for an assumed albedo range of 0.20–0.04 respectively).^[5]

• Understanding the Distribution of Near-Earth Asteroids Bottke, W. F., Jedicke, R., Morbidelli, A., Petit, J.-M., Gladman, B. 2000, Science, Vol. 288, Issue 5474, pp. 2190–2194.
• A Numerical Survey of Transient Co-orbitals of the Terrestrial Planets Christou, A. A. 2000, Icarus, Vol. 144, Issue 1, pp. 1–20.
• Debiased Orbital and Absolute Magnitude Distribution of the Near-Earth Objects Bottke, W. F., Morbidelli, A., Jedicke, R., Petit, J.-M., Levison, H. F., Michel, P., Metcalfe, T. S. 2002, Icarus, Vol. 156, Issue 2, pp. 399–433.
• Transient co-orbital asteroids Brasser, R., Innanen, K. A., Connors, M., Veillet, C., Wiegert, P., Mikkola, S., Chodas, P. W. 2004, Icarus, Vol. 171, Issue 1, pp. 102–109.
• A trio of horseshoes: past, present and future dynamical evolution of Earth co-orbital asteroids 2015 XX₁₆₉, 2015 YA and 2015 YQ₁ de la Fuente Marcos, C., de la Fuente Marcos, R. 2016, Astrophysics and Space Science, Vol. 361, Issue 4, article 121 (13 pp).

• Discovery MPEC
• 2020 PP₁ data at MPC
• 2020 PP1 at NeoDyS-2, Near Earth Objects—Dynamic Site
  • Ephemerides · Observation prediction · Orbital info · MOID · Proper elements · Observational info · Close approaches · Physical info · Orbit animation
• 2020 PP1 at ESA–space situational awareness
  • Ephemerides · Observations · Orbit · Physical properties · Summary
• 2020 PP1 at the JPL Small-Body Database
  • Close approach · Discovery · Ephemeris · Orbit viewer · Orbit parameters · Physical parameters