1998 WW31

From Wikipedia, the free encyclopedia
Jump to: navigation, search
1998 WW31
Artist's impression of 1998 WW31.jpg
Artist's Impression of 1998 WW31 and its satellite
Discovered by Deep Ecliptic Survey
Discovery date 18 November 1998
MPC designation 1998 WW31
Trans-Neptunian object
Orbital characteristics
Epoch 14 June 2006 (JD 2453900.5)
Aphelion 48.419 AU (7243.350 Gm)
Perihelion 40.559 AU (6067.553 Gm)
44.489 AU (6655.451 Gm)
Eccentricity 0.088
296.75 a (108386.849 d)
4.46 km/s
Inclination 6.818°
Known satellites 1
Physical characteristics
Dimensions 133±15 km
Mass 1.3–2.5×1018 kg (system)
Mean density
1.5 g/cm³ (assumed)
0.025–0.031 m/s²
0.054–0.068 km/s
570 d (system orbital period)
Albedo 0.05–0.09 (assumed)
Temperature ~42 K

1998 WW31 (also written 1998 WW31) is a double Kuiper belt object. It was discovered in 1998 by the Deep Ecliptic Survey (DES).

1998 WW31 forms a binary system with another object with the IAU provisional designation S/2000 (1998 WW31) 1: the first trans-Neptunian binary to be discovered since Pluto, and one of the most symmetrical binaries known in the Solar System. The two bodies are very close in size, with a diameter ratio of 1.2 and a mass ratio of 1.74, assuming similar surfaces and densities. Their orbital period is approximately 570 days, and they orbit at a distance of approximately 4000 km (closest approach) to 40,000 km, with a semi-major axis of about 22,000 km. Their diameters are likely to be in the 100–150 km range, assuming a density of 1–2 g/cm³. Their combined mass is 1/6000th that of the Pluto–Charon system.


External links[edit]