C/1999 H3 LINEAR
more info
C/1999 H3 was discovered as an apparently asteroidal object by LINEAR on 22 April 1999 (about four months before perihelion passage). Next day was reported as cometary object by observers from Klet and Ondrejov [IAUC 7151, 1999 April 23].

This comet made its closest approach to Earth on 6 March 2000 (3.185 au), about 7.5 months after perihelion.

Solution given here is based on data span over 2.9 yr in a range of heliocentric distances: 3.66 au – 3.501 au (perihelion) – 8.48 au.

NG orbits using full data-arc as well as using post-perihelion data are determinable.

See also Królikowska and Dones 2023, Królikowska and Dybczyński 2017,and Królikowska 2014.
solution description
number of observations 879
data interval 1999 04 22 – 2002 03 20
data type significantly more measurements after perihelion (POST+)
data arc selection entire data set (STD)
range of heliocentric distances 3.66 au – 3.50 au (perihelion) – 8.48 au
type of model of motion NS - non-gravitational orbits for standard g(r)
data weighting YES
number of residuals 1708
RMS [arcseconds] 0.50
orbit quality class 1a
orbital elements (barycentric ecliptic J2000)
Epoch 2302 02 03
perihelion date 1999 08 17.97915451 ± 0.00044404
perihelion distance [au] 3.50202184 ± 0.00000342
eccentricity 1.00003611 ± 0.00000399
argument of perihelion [°] 101.885395 ± 0.000095
ascending node [°] 332.815353 ± 0.000011
inclination [°] 115.893742 ± 0.000015
reciprocal semi-major axis [10-6 au-1] -10.31 ± 1.14
file containing 5001 VCs swarm
1999h3kn.bpl
Upper panel: 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.
Middle panel(s): O-C diagram for a given solution (sometimes in comparison to another solution available in CODE), where residuals in right ascension are shown using magenta dots and in declination by blue open circles.
Lowest panel: Relative weights for a given data set(s).
Six 2D-projections of the 6D space of future swarm including 5001 VCs. Each density map is given in logarithmic scale presented on the right in the individual panel.