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Tuesday 3 April 2012

2010 EK139 - 20th Largest TNO?

2010 EK139 is a large, 2:7 resonant trans-Neptunian object.

Discovery

2010 EK139 was discovered on March 13, 2010 by astronomers from the OGLE team led by Andrzej Udalski from Warsaw University.

There are precovery images dating back to 2002.

Stats

Estimated Diameter: 677 km (462 – 1033 km)
Aphelion: 106.25 AU
Perihelion: 32.49 AU
Semi-major axis: 68.91 AU
Orbital Period: 572 years
Rotation period: ? hrs
Date discovered: 2010.3.13
Satellite: 0
Classification: TNO, 2:7 resonance

Orbit

2010 EK139 will come to perihelion around 2038, and is currently 39.1 AU from the Sun.

2010 EK139 has been observed 122 times over 5 oppositions and has an orbit quality of 2 [JPL ranks orbital quality from 0 to 9 (0 being best)].

A ten million year integration of the orbit shows that 2010 EK139 may be in a 7:2 resonance with Neptune.

How big is it?

2010 EK139 is so far away in the outer solar system that we don't know for sure how large it is. Because all we see is a dot of light, which is sunlight reflected off the surface of the TNO. But we don't know if the object is bright because it is large or if it is bright because it is highly reflective or both.

Dwarf-planet candidate

Assuming a generic trans-Neptunian albedo of 0.09, but since the true albedo is unknown and it has an absolute magnitude of 3.8, 2010 EK139 could easily be from about 462 to 1033 km in diameter.

Mike Brown lists 2010 EK139 as highly likely dwarf planet.

1 comment:

  1. Where is it in the southern hemisphere sky-direction and altitude?

    ReplyDelete