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2017 SN16, is a sub-kilometer asteroid, classified as a near-Earth object of the Apollo group, approximately 90 meters (300 feet) in diameter. The object was first observed on 24 September 2017, by cometary discoverer Alex Gibbs with the Mount Lemmon Survey at Mount Lemmon Observatory, Arizona, in the United States. It forms an asteroid pair with 2018 RY7 and is currently trapped in a 3:5 mean motion resonance with Venus.
2020 VT1 is a small asteroid, classified as a near-Earth object of the Amor group, that is a temporary horseshoe companion to Mars.
2020 PN1 is a sub-kilometer asteroid, classified as a near-Earth object of the Aten group, that is a temporary horseshoe companion to the Earth. There are dozens of known Earth horseshoe librators, some of which switch periodically between the quasi-satellite and the horseshoe co-orbital states.
References
- 1 2 3 "MPEC 2020-P68 : 2020 PP1". Minor Planet Electronic Circular. Minor Planet Center. 13 August 2020. Retrieved 20 January 2021.
- 1 2 "2020 PP1". Minor Planet Center. International Astronomical Union. Retrieved 3 August 2021.
- ↑ "2020 PP1". NEO Exchange. Las Cumbres Observatory. 13 August 2020. Retrieved 3 August 2021.
- 1 2 3 4 "JPL Small-Body Database Browser: 2020 PP1" (2021-08-01 last obs.). Jet Propulsion Laboratory . Retrieved 3 August 2021.
- 1 2 Bruton, Dan. "Conversion of Absolute Magnitude to Diameter for Minor Planets". Department of Physics, Engineering, and Astronomy. Stephen F. Austin State University. Archived from the original on 23 July 2011. Retrieved 3 August 2021.
- 1 2 de la Fuente Marcos, Carlos; de la Fuente Marcos, Raúl (March 2021). "Using Mars co-orbitals to estimate the importance of rotation-induced YORP break-up events in Earth co-orbital space". Monthly Notices of the Royal Astronomical Society . 501 (4): 6007–6025. arXiv: 2101.02563 . Bibcode:2021MNRAS.501.6007D. doi:10.1093/mnras/stab062.
- ↑ "MPEC 2021-P17 : 2020 PP1". Minor Planet Electronic Circular. Minor Planet Center. 3 August 2021. Retrieved 3 August 2021.
