![]() Canada-France-Hawaii Telescope image of split asteroid pair P/2016 J1 on 6 May 2016, showing comet-like tails on both components | |
Discovery[1] | |
---|---|
Discovered by | Pan-STARRS 1 |
Discovery site | Haleakalā Observatory |
Discovery date | 5 May 2016 |
Designations | |
P/2016 J1 | |
Orbital characteristics (fragment A)[2] | |
Epoch | 21 June 2016 (JD 2457560.5) |
Observation arc | 153 days (A)[2] 140 days (B)[3] |
Earliest precovery date | 4 March 2016[2] |
Orbit type | main-belt (outer)[4] · Encke-type[2][3] · periodic[5][6] |
Aphelion | 3.896 AU |
Perihelion | 2.448 AU |
Semi-major axis | 3.172 AU |
Eccentricity | 0.2283 |
Orbital period | 5.65 yr (2,064 days) |
Inclination | 14.330° |
199.856° | |
Argument of periapsis | 46.585° |
Last perihelion | 24 June 2016[2] |
TJupiter | 3.113 |
Earth MOID | 1.461 AU |
Jupiter MOID | 1.227 AU |
Physical characteristics | |
Mean diameter | <0.62+0.18 −0.10 km (A)[7]: 18 <0.34+0.12 −0.06 m (B)[7]: 18 |
0.04 (assumed)[4] | |
C/G[8] B–V = 0.74±0.04 (A)[8] B–V = 0.74±0.12 (B)[8] V–R = 0.36±0.04 (A)[8] V–R = 0.39±0.12 (B)[8] | |
Comet total magnitude (M1) | 16.4±0.4 (A)[2] 17.3±0.8 (B)[3] |
Comet nuclear magnitude (M2) | >19.95+0.18 −0.16 (A)[7]: 18 >21.26+0.23 −0.26 (B)[7]: 18 |
P/2016 J1 (PanSTARRS) is a pair of active main-belt asteroids that split apart from each other in early 2010. The brightest and largest component of the pair, P/2016 J1-A, was discovered first by the Pan-STARRS 1 survey at Haleakalā Observatory on 5 May 2016. Follow-up observations by the Canada-France-Hawaii Telescope at Mauna Kea Observatory discovered the second component, P/2016 J1-B, on 6 May 2016.[9] Both asteroids are smaller than 1 kilometre (0.62 mi) in diameter, with P/2016 J1-A being roughly 0.6 km (0.37 mi) in diameter and P/2016 J1-B being roughly 0.3 km (0.19 mi) in diameter.[7]: 18 The two components recurrently exhibit cometary activity as they approach the Sun near perihelion, suggesting that their activity is driven by sublimation of volatile compounds such as water.[7]
In 2018, an orbit analysis by Hsieh et al. found that both components of P/2016 J1 are related to the Theobalda asteroid family of C-, F-, and X-type asteroids. The Theobalda family likely originated as fragments from an impact event that shattered a 78 ± 9 km (48 ± 6 mi)-diameter parent body 6.9±2.3 million years ago.[10]: 10 Another ice-sublimating active asteroid, 427P/ATLAS (P/2017 S5), was also identified to be part the Theobalda family, suggesting that some members of this family were able to retain subsurface water ice since the collision that formed them.[11]: 7