| Discovery [1] [2] | |
|---|---|
| Discovered by |
S. S. Sheppard C. Trujillo |
| Discovery site | Las Campanas Obs. |
| Discovery date | 16 October 2004 |
| Designations | |
| (385571) Otrera | |
Named after | Otrera ( Greek mythology) [2] |
| 2004 UP10 | |
|
Neptune trojan ·
L4
[3] centaur [1] · distant [2] | |
| Orbital characteristics [1] | |
| Epoch 4 September 2017 ( JD 2458000.5) | |
| Uncertainty parameter 4 | |
| Observation arc | 8.97 yr (3,277 days) |
| Aphelion | 30.727 AU |
| Perihelion | 29.327 AU |
| 30.027 AU | |
| Eccentricity | 0.0233 |
| 164.54 yr (60,099 days) | |
| 355.52 ° | |
| 0° 0m 21.6s / day | |
| Inclination | 1.4334° |
| 34.761° | |
| 3.5334° | |
| Physical characteristics | |
| Dimensions | 74 km (est. at
0.10)
[4] 100 km [5] |
| 23.3 [5] | |
| 8.8 [1] | |
385571 Otrera, provisional designation 2004 UP10, is a Neptune trojan leading Neptune's orbit in the outer Solar System. It was discovered by American astronomers Scott Sheppard and Chad Trujillo at Las Campanas Observatory on 16 October 2004. [2] It measures approximately 100 kilometers in diameter and was the second such body to be discovered after 2001 QR322. [3]
Orbit and classification
Neptune trojans are resonant trans-Neptunian objects in a 1:1 mean-motion orbital resonance with Neptune. These Trojans have a semi-major axis and an orbital period very similar to Neptune's (30.10 AU; 164.8 years).
Otrera belongs to the L4 group, which leads 60 ° ahead Neptune's orbit. It orbits the Sun with a semi-major axis of 30.027 AU at a distance of 29.3–30.7 AU once every 164 years and 6 months (60,099 days). Its orbit has an eccentricity of 0.02 and an inclination of 1 ° with respect to the ecliptic. [1]
Physical characteristics
The discoverers estimate that the body has a mean-diameter of 100 kilometers based on a magnitude of 23.3. [5] Based on a generic magnitude-to-diameter conversion, it measures approximately 74 kilometers in diameter using an absolute magnitude of 8.8 and an assumed albedo of 0.10. [4]
Naming
This minor planet was the first Neptune trojan to be named in November 2015. It was named after Otrera, the first Amazonian queen in Greek mythology. [2] The naming scheme is to name these objects after figures related to the Amazons, which was an all-female warrior tribe that fought in the Trojan War on the side of the Trojans against the Greeks. [6]
References
- ^ a b c d e "JPL Small-Body Database Browser: 385571 Otrera (2004 UP10)" (2013-10-06 last obs.). Jet Propulsion Laboratory. Retrieved 4 August 2017.
- ^ a b c d e "385571 Otrera (2004 UP10)". Minor Planet Center. Retrieved 4 August 2017.
- ^ a b "List Of Neptune Trojans". Minor Planet Center. 10 July 2017. Retrieved 4 August 2017.
- ^ a b "Asteroid Size Estimator". CNEOS/JPL. Retrieved 2 August 2017.
- ^ a b c Lakdawalla, Emily (13 August 2010). "2008 LC15, the first Trojan asteroid discovered in Neptune's L5 point". The Planetary Society. Retrieved 4 August 2017.
- ^ Ticha, J.; et al. (10 April 2018). "DIVISION F / Working Group for Small Body Nomenclature Working Group for Small Body Nomenclature. THE TRIENNIAL REPORT (2015 Sept 1 - 2018 Feb 15)" (PDF). IAU. Retrieved 25 August 2018.
External links
- Scott Sheppard and the hunt for Neptune Trojans on YouTube (time 1:40 min.)
- 385571 Otrera at AstDyS-2, Asteroids—Dynamic Site
- 385571 Otrera at the JPL Small-Body Database
