(278361) 2007 JJ43

(278361) 2007 JJ₄₃ is a large trans-Neptunian object (TNO) orbiting the Sun near the outer edge of the Kuiper belt. Its discovery images were taken in 2007, and its absolute magnitude of 4.5 is one of the twenty brightest exhibited by TNOs. Assuming it has a typical albedo, this would make it roughly the same size as Ixion (about 530–620 km diameter). In a paper in the Astrophysical Journal Letters András Pál and colleagues estimate a diameter for (278361) 2007 JJ₄₃ of 610+170
−140 km.^[7]

(278361) 2007 JJ₄₃

Discovery[1]
Discovered by	Palomar Obs.
Discovery site	Palomar Obs.
Discovery date	14 May 2007
Designations
Alternative designations	2007 JJ43
Minor planet category	TNO[1][2] · ScatNear[3]
Orbital characteristics[4][1]
Epoch 27 August 2011 (JD 2455800.5)
Uncertainty parameter 2
Observation arc	4813 days (13.18 yr)
Earliest precovery date	10 May 2002 (NEAT)
Aphelion	55.3707 AU
Perihelion	40.2776 AU
Semi-major axis	47.82 AU
Eccentricity	0.1578
Orbital period (sidereal)	330.74 a (120801 d)
Mean anomaly	331.84°
Inclination	12.0623°
Longitude of ascending node	272.493°
Time of perihelion	≈ 2 April 2037[5] ±6 days
Argument of perihelion	9.02°
Physical characteristics
Mean diameter	530 km (est. at 0.08)[6] 457 km (est. at 0.135)[2] 610+170 −140 km[7]
Synodic rotation period	12.097 h[7] 6.04 h[1]
Geometric albedo	0.13[7]
Apparent magnitude	20.8[8]
Absolute magnitude (H)	3.2 (R-band)[9] 4.5[1]

Observations by Mike Brown in 2012, using the W. M. Keck Observatory, suggest that (278361) 2007 JJ₄₃ does not have a companion.^[10]

As of 2014^[update], it is about 41.3 AU from the Sun.^[8]

See also

• List of Solar System objects by size