|Discovered by||M. E. Van Ness|
LONEOS telescope at Lowell Observatory
|Discovery date||28 July 2001|
|Orbital characteristics A|
|Epoch||15 December 2001|
|Observation arc||340 days|
|Aphelion||25.606 AU (Q)|
|Perihelion||0.99404 AU (q)|
|Semi-major axis||13.300 AU (a)|
|Orbital period||48.51 yr|
|Earth MOID||0.3 AU (45 million km)|
|Dimensions||13.6 ± 1.0 km|
C/2001 OG108 (LONEOS) is a Halley-type comet with an orbital period of 48.51 years. It was discovered on 28 July 2001 by the LONEOS telescope at Lowell Observatory. Of the short-period comets with known diameters and perihelion inside the orbit of Earth, C/2001 OG108 is the second largest after Comet Swift–Tuttle.
Observations taken in January and February 2002 showed that the "asteroid" had developed a small amount of cometary activity as it approached perihelion. It was subsequently reclassified as a comet. The comet came to perihelion (closest approach to the Sun) on 15 March 2002. It will come to aphelion in 2026 and the next perihelion passage is calculated to be on 6 June 2050. On 23 March 2147 the comet will pass about 0.42 AU (63 million km; 160 LD) from Earth with an uncertainty region of about ±2 million km.
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. 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.
This comet probably represents the transition between typical Halley-family/long-period comets and extinct comets. Damocloids have been studied as possible extinct cometary candidates due to the similarity of their orbital parameters with those of Halley-family comets.
- Abell, 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. Bibcode:2003LPI....34.1253A.
- French, 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.
- "JPL Small-Body Database Browser: C/2001 OG108 (LONEOS)" (last observation: 2002-07-03; arc: 340 days). Jet Propulsion Laboratory. Retrieved 18 May 2011.
(Close approach uncertainty: (MaxDist of 0.434) – (MinDist of 0.408) * 149597870.7 = 3.9 million km)
- Horizons output. "Observer Table for Comet C/2001 OG108 (LONEOS)" (Soln.date: 2014-Jun-18). Retrieved 2 August 2020. (Observer Location:@sun Perihelion occurs when deldot flips from negative to positive)
- "JPL Small-Body Database Search Engine: comets and q < 1 (au) and period < 200 (years)". JPL Solar System Dynamics. Retrieved 24 July 2020.