C/2001 OG108 (LONEOS)


C/ 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/ is the second largest after Comet Swift–Tuttle.

Orbit

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 on 15 March 2002. It will come to aphelion in 2026 and the next perihelion passage is calculated to be on 7 June 2050. On 23 March 2147 the comet will pass about from Earth with an uncertainty region of about ±2 million km.
Date & time of
closest approach		Earth distance
Sun distance
Velocity
wrt Earth
Velocity
wrt Sun
Uncertainty
region
Reference
2147-03-23 11:20 ± 13:3840.335.3± 2 million 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.

Physical properties

The comet has a rotational period of 2.38 ± 0.02 days .
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. Using data from Fernandez JPL lists the comet with an albedo of 0.05 and a diameter of