C/2011 J2 (LINEAR)

For other comets of the same name, see List of comets discovered by the LINEAR project.

C/2011 J2 (LINEAR) is an Oort cloud comet discovered on 4 May 2011 by LINEAR at an apparent magnitude of 19.7 using a 1 m (39 in) reflecting telescope.^[1][2] The comet reached an apparent magnitude 17.0 on September 2014.^[5]

C/2011 J2 (LINEAR)

Discovery[1][2]
Discovery site	LINEAR (704)
Discovery date	4 May 2011
Designations
Alternative designations	CK11J020
Orbital characteristics[3][4]
Epoch	22 January 2014 (JD 2456679.5)
Observation arc	6.52 years
Earliest precovery date	10 March 2011
Number of observations	6,434
Orbit type	Oort cloud
Aphelion	~49,940 AU (inbound)
Perihelion	3.443 AU
Semi-major axis	~25,000 AU (inbound)
Eccentricity	0.99986 (inbound) 1.00004 (outbound)
Orbital period	3.95 million years (inbound)
Inclination	122.80°
Longitude of ascending node	163.95°
Argument of periapsis	85.296°
Last perihelion	25 December 2013
TJupiter	-1.258
Earth MOID	3.004 AU
Jupiter MOID	0.551 AU
Comet total magnitude (M1)	7.7
Comet nuclear magnitude (M2)	10.3

Observational history

C/2011 J2 came to perihelion on 25 December 2013 at a distance of 3.4 AU (510 million km) from the Sun.^[5] On 27 August 2014 an 18th magnitude fragment CK11J02b was detected.^[5] Preliminary estimates are that a fragmentation event occurred around 14 July 2014 plus/minus ten days.^[6] In mid-July 2014 the comet was 3.9 AU (580 million km) from the Sun.

Fragment C was detected in October 2014 by Ernesto Guido, Nick Howes, and Martino Nicolini.^[7]

C/2011 J2 is dynamically new. It came from the Oort cloud with a loosely bound chaotic orbit that was easily perturbed by galactic tides and passing stars. Before entering the planetary region (epoch 1800), C/2011 J2 had an orbital period of several million years.^[3] After leaving the planetary region (epoch 2200), it will be on an ejection trajectory.^[3]