C/2000 W1 (Utsunomiya–Jones)

C/2000 W1 (Utsunomiya–Jones) is a non-periodic comet from the Oort cloud discovered on 18 November 2000, by Syogo Utsunomiya and Albert F. A. L. Jones.^[7] The comet reached up to apparent magnitude 5.5,^[6] but was only 27 degrees from the Sun in mid-December 2000.^[8]

C/2000 W1 (Utsunomiya–Jones)

Discovery[1]
Discovered by	Syogo Utsunomiya Albert F. A. L. Jones
Discovery site	Aso, Kumamoto, Japan MJUO, New Zealand
Discovery date	18 November 2000
Orbital characteristics[2][3]
Epoch	11 December 2000 (JD 2451889.5)
Observation arc	58 days
Number of observations	440
Aphelion	~70,000 AU (inbound) ~1,670 AU (outbound)
Perihelion	0.321 AU
Semi-major axis	~35,000 AU (inbound) ~835 AU (outbound)
Eccentricity	0.9999996
Orbital period	millions of years (inbound) ~24,000 years (outbound)
Max. orbital speed	74.3 km/s (166,000 mph)[4]
Inclination	160.16°
Longitude of ascending node	10.766°
Argument of periapsis	51.509°
Last perihelion	26 December 2000
Next perihelion	Disintegrated[5]
TJupiter	–0.661
Earth MOID	0.101 AU
Jupiter MOID	0.838 AU
Physical characteristics
Comet total magnitude (M1)	12.6
Comet nuclear magnitude (M2)	20.5
Apparent magnitude	5.5 (2000 apparition)[6]

Orbit

The comet has an observation arc of 58 days allowing a reasonable estimate of the orbit. Though the near-perihelion orbit solution shows the comet to be on a hyperbolic trajectory,^[3] the orbit of a long-period comet is properly obtained when the osculating orbit is computed at an epoch after leaving the planetary region and is calculated with respect to the center of mass of the Solar System. Using JPL Horizons, the barycentric orbital elements for epoch 2020-Jan-01 generate a semi-major axis of 835 AU (124,900 million km), an aphelion distance of 1,670 AU (250,000 million km), and a period of approximately 24,000 years.^[2]

C/2000 W1 came to perihelion on 26 December 2000 when it passed 0.321 AU (48.0 million km) from the Sun.^[3] It was last observed in February–March 2001 when it faded suddenly and probably disintegrated.^[5][9]