Observations taken in January and February 2002 showed that the "asteroid" had developed a small amount of cometary activity as it approached perihelion.[1] It was subsequently reclassified as a comet.[1] The comet came to perihelion (closest approach to the Sun) on 15 March 2002.[3] It will come to aphelion in 2026 and the next perihelion passage is calculated to be on 7 June 2050.[4] On 23 March 2147 the comet will pass about 0.42 AU (63 million km; 160 LD) from Earth[3] with an uncertainty region of about ±2 million km.[6]
C/2001 OG108 (LONEOS) Closest Earth Approach on 2147-Mar-23 11:20 UT[3]
The comet has a rotational period of 2.38 ± 0.02 days (57.12 hr).[1][3]
In 2003, the comet was estimated to have a mean absolute V magnitude (H) of 13.05 ± 0.10, with an albedo of 0.03, giving an effective radius of 8.9 ± 0.7 km.[1] Using data from Fernandez (2004–2005) JPL lists the comet with an albedo of 0.05 and a diameter of 13.6 ± 1.0 km.[3]
This comet probably represents the transition between typical Halley-family/long-period comets and extinct comets.[1]Damocloids have been studied as possible extinct cometary candidates due to the similarity of their orbital parameters with those of Halley-family comets.[1]
^ abcdefgAbell, Paul A.; Fernández, Yanga R.; Pravec, Petr; French, Linda M.; Farnham, Tony L.; Gaffey, Michael J.; Hardersen, Paul S.; Kušnirák, Peter; Šarounová, Lenka; Sheppard, Scott S. (2003). "Physical Characteristics of Asteroid-like Comet Nucleus C/2001 OG108 (LONEOS)". 34th Annual Lunar and Planetary Science Conference: 1253. Bibcode:2003LPI....34.1253A.
^ abFrench, Linda M. (2002). "Pre-Activity BVRI Colors of High-Inclination Comet C/2001 OG108 (LONEOS)". American Astronomical Society, DPS Meeting No. 34, #16.01. 34: 868. Bibcode:2002DPS....34.1601F.
