Discovery [1] | |
---|---|
Discovered by | S. S. Sheppard D. J. Tholen C. Trujillo |
Discovery site | Mauna Kea Obs. |
Discovery date | 5 September 2021 |
Designations | |
2021 RR205 | |
TNO [2] · detached · distant [3] | |
Orbital characteristics (barycentric) [4] | |
Epoch 25 February 2023 (JD 2460000.5) | |
Uncertainty parameter 3 [2] | |
Observation arc | 5.11 yr (1,867 days) |
Earliest precovery date | 24 July 2017 |
Aphelion | 1926 AU |
Perihelion | 55.541 AU |
990.9 AU | |
Eccentricity | 0.94395 |
31173 yr | |
0.363° | |
0° 0m 0.114s / day | |
Inclination | 7.644° |
108.345° | |
208.574° | |
Physical characteristics | |
100–300 km (est. 0.04–0.2) [5] | |
24.6 [1] | |
6.77±0.11 [2] ·6.74 [3] | |
2021 RR205 is an extreme trans-Neptunian object discovered by astronomers Scott Sheppard, David Tholen, and Chad Trujillo with the Subaru Telescope at Mauna Kea Observatory on 5 September 2021. It resides beyond the outer extent of the Kuiper belt on a distant and highly eccentric orbit detached from Neptune's gravitational influence, with a large perihelion distance of 55.5 astronomical units (AU). [4] Its large orbital semi-major axis (~1,000 AU) suggests it is potentially from the inner Oort cloud. [6] [7] 2021 RR205 and 2013 SY99 both lie in the 50–75 AU perihelion gap that separates the detached objects from the more distant sednoids; dynamical studies indicate that such objects in the inner edge of this gap weakly experience "diffusion", or inward orbital migration due to minuscule perturbations by Neptune. [6] While Sheppard considers 2021 RR205 a sednoid, researchers Yukun Huang and Brett Gladman do not. [8]
2021 RR205's heliocentric distance was 60 AU when it was discovered. [2] It has been detected in precovery observations by the Dark Energy Survey at Cerro Tololo Observatory from as early as July 2017. [3] It last passed perihelion in the early 1990s and is now moving outbound from the Sun. [1]