C/1958 R1 Burnham-Slaughter
more info
Comet C/1958 R1 was discovered on 7 September 1958 by Robert Burnham Jr and Charles D. Slaughter during the course of proper motion survey at Lowell Observatory (Flagstaff, Arizona,USA) [Kronk, Cometography: Volume 4], that is 6 months before its perihelion passage. C/1958 R1 was followed until 21 April 1960.

Comet had its closest approach to the Earth on 19 September 1958 (1.92 au, at this moment comet was 2.74 au from the Sun) and 18 March 1959 (1.94 au, six days after its perihelion passage).The MPC cometary database presents GR orbit based of 85 positional observations (data arc: 1958 09 07 – 1960 04 21), however only 40 observations obtained in Flagstaff are available in the MPC (data arc: 1958 09 14 – 1960 04 21), and the JPL offers GR osculating orbit based on this data set. We additionally collected observations from Yerkes, McDonald and Skalnaté Pleso observatories published in literature, and orbits 'ba' (GR) and 'bn' (NG) are based on 95 positional measurements (data arc: 1958 09 12 – 1960 04 21). For comparison purposes, we also presented orbits (GR and NG) using only Flagstaff data set (this set gives notable better rms for both types of orbits).

This is a comet with NG effects strongly manifested in positional data fitting. Solutions 'ba' and 'bn' are based on data spanning over 1.6 yr in a range of heliocentric distances: 2.81 au – 1.63 au (perihelion) – 4.92 au.

This Oort spike comet suffers moderate planetary perturbations while passing through the planetary system; these perturbations lead to more tight future orbit (see future barycentric orbits).
solution description
number of observations 97
data interval 1958 09 12 – 1960 04 21
data type perihelion within the observation arc (FULL)
data arc selection entire data set (STD)
range of heliocentric distances 2.81 au – 1.63 au (perihelion) – 4.92 au
detectability of NG effects in the comet's motion comet with NG effects strongly manifested in positional data fitting
type of model of motion GR - gravitational orbit
data weighting YES
number of residuals 188
RMS [arcseconds] 1.76
orbit quality class 1b
orbital elements (heliocentric ecliptic J2000)
Epoch 1959 03 13
perihelion date 1959 03 11.51986102 ± 0.00035757
perihelion distance [au] 1.62819870 ± 0.00000188
eccentricity 0.99987072 ± 0.00000847
argument of perihelion [°] 100.736249 ± 0.000160
ascending node [°] 323.778603 ± 0.000092
inclination [°] 61.257286 ± 0.000116
reciprocal semi-major axis [10-6 au-1] 79.40 ± 5.20
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).