{{Short description|Two asteroids that were once in binary}} An '''asteroid pair''', or (if more than two bodies) an '''asteroid cluster''', are asteroids which at some point in the past had very small relative velocities, and are typically formed either by a collisional break-up of a parent body, or from binary asteroids which became gravitationally unbound and are now following similar but different orbits around the Sun.<ref name="johnstonsarchive-asteroid-pair"/>
A possible example of a pair are the Trojan asteroids 1583 Antilochus and 3801 Thrasymedes. The proposer of that pair, Andrea Milani, found five other potential asteroid clusters in the Greek camp, clustered around the asteroids 1437 Diomedes, 1647 Menelaus, 2456 Palamedes, 2797 Teucer and 4035 Thestor.<ref name="Milani-1993"/>
The youngest asteroid pairs discovered {{asof|2022|lc=y}} include the main-belt asteroids P/2016 J1-A/B (separated c. 2010) and {{mp|(458271) 2010 UM|26}}/{{mp|(796785) 2010 RN|221}} (separated c. 2003).<ref name="Moreno2017"/><ref name="Vokrouhlicky12022"/> The former pair is particularly remarkable for exhibiting comet-like activity due to water ice sublimation and rotational break-up.<ref name="Moreno2017"/>
==References== <references>
<ref name="johnstonsarchive-asteroid-pair">{{cite web |title = Asteroid pairs and clusters |work = Johnston's Archive |date = 29 April 2018 |author = Johnston, Wm. Robert |url = http://www.johnstonsarchive.net/astro/asteroidpairs.html |access-date = 30 June 2018}}</ref>
<ref name="Milani-1993">{{Cite journal |author = Milani, Andrea |date = October 1993 |title = The Trojan asteroid belt: Proper elements, stability, chaos and families |journal = Celestial Mechanics and Dynamical Astronomy |volume = 57 |issue = 1–2 |pages = 59–94 |issn = 0923-2958 |bibcode = 1993CeMDA..57...59M |doi = 10.1007/BF00692462 |s2cid = 189850747}}</ref>
<ref name="Moreno2017">{{cite journal |display-authors = etal |first1 = F. |last1 = Moreno |first2 = F. J. |last2 = Pozuelos |first3 = B. |last3 = Novaković |first4 = J. |last4 = Licandro |first5 = A. |last5 = Cabrera-Lavers |first6 = B. |last6 = Bolin |title = The Splitting of Double-component Active Asteroid P/2016 J1 (PANSTARRS) |url = http://www2.ess.ucla.edu/~jewitt/papers/2017/HJD17.pdf |journal = The Astrophysical Journal Letters |date = March 2017 |volume = 837 |issue = 1 |id = L3 |pages = 6 |doi-access = free |doi = 10.3847/2041-8213/aa6036 |arxiv = 1702.03665 |bibcode = 2017ApJ...837L...3M|hdl = 2268/290351 }}</ref>
<ref name="Vokrouhlicky12022">{{cite journal |first1 = D. |last1 = Vokrouhlický |first2 = P. |last2 = Fatka |first3 = M. |last3 = Micheli |first4 = P. |last4 = Pravec |first5 = E. J. |last5 = Christensen |title = Extremely young asteroid pair (458271) 2010 UM26 and 2010 RN221 |url = https://astro.troja.mff.cuni.cz/davok/papers/young_pair_AA2022.pdf |journal = Astronomy & Astrophysics |date = August 2022 |volume = 664 |id = L17 |pages = 6 |doi-access = free |doi = 10.1051/0004-6361/202244589 |arxiv = 2208.06207 |bibcode = 2022A&A...664L..17V}}</ref>
</references>
{{Asteroids}}
Category:Asteroid groups and families Category:Asteroids