C/2004 X3 LINEAR

Solar System
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C/2004 X3 LINEAR

General description

C/2004 X3 was discovered on 15 December 2004 by the LINEAR as an apparently asteroidal object. In the following week its cometary apperance was reported by observers [IAUC 8457, 2004 December 21].

This comet made its closest approach to Earth on 9 March 2005 (3.499 au), 3.3 months before perihelion.

Solution given below is based on data span over 1.3 yr in a range of heliocentric distances: 4.65 au – 4.402 au (perihelion) – 4.98 au.

Figure caption: Time distribution of positional observations with corresponding heliocentric (red curve) and geocentric (green curve) distance at which they were taken. The horizontal dotted line shows the perihelion distance for a given comet whereas vertical dotted line — the moment of perihelion passage.

SSDP Cometary Note C2004X3A2-001

Comet C/2004 X3 LINEAR

number of observations	250
number of residuals	487
data interval	2004 Dec. 15 — 2006 Mar. 31
rms [arcsec]	0.51
orbit quality class	1a

Osculating orbital elements (heliocentric; ecliptic J2000.0)

Epoch (TT)	20050530.0	= JD 2453520.5
time of perihelion passage (TT)	20050617.237423	± 0.001410
perihelion distance	4.40225166	± 0.00000568
eccentricity	1.00625095	± 0.00000937
argument of perihelion [deg]	202.133519	± 0.000207
longitude of the ascending node [deg]	343.045098	± 0.000014
inclination [deg]	81.063070	± 0.000082
inverse semimajor axis [10^-6 au^-1]	-1419.94	± 2.13

Note: Epoch is given in a format: yyyymmdd.d, time of perihelion passage in a format of yyyymmdd.dddddd.

Figure caption: Six 2D-projections of the 6D space of original swarm (5001 VCs) of C/2004 X3. Each density map is given in logarithmic scale presented on the right in the individual panel.
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Original orbital elements (barycentric; at 250 au from the Sun)

Epoch (TT)	17010414
time of perihelion passage (TT)	20050618.219538	± 0.001403
perihelion distance	4.38911289	± 0.00000571
eccentricity	0.99994104	± 0.00000930
argument of perihelion [deg]	202.411327	± 0.000206
longitude of the ascending node [deg]	343.029540	± 0.000014
inclination [deg]	81.169463	± 0.000081
inverse semimajor axis [10^-6 au^-1]	13.43	± 2.12

Note: Values of uncertainties of original/future orbital elements were derived using a swarm of 5001 osculating orbits of VCs (including the nominal osculating orbit given above) for original/future orbital evolution calclulations and then by fitting the distribution of a given orbital element of original/future swarm of VCs to Gaussian distribution.

Original barycentric positions and velocities of 5001 VCs at 250 au from the Sun are given here (data format), i.e. before entering the planetary zone.

Future orbital elements (barycentric; at 250 au from the Sun)

Epoch (TT)	23020603
time of perihelion passage (TT)	20050616.645926	± 0.001397
perihelion distance	4.39810248	± 0.00000560
eccentricity	1.00281265	± 0.00000933
argument of perihelion [deg]	202.017151	± 0.000206
longitude of the ascending node [deg]	343.041981	± 0.000014
inclination [deg]	81.093110	± 0.000081
inverse semimajor axis [10^-6 au^-1]	-639.51	± 2.12