C/1975 E1 Bradfield
more info
Comet C/1975 E1 was discovered on 12 March 1975 by William A. Bradfield (Dernancourt, South Australia, Australia), that is about 3 weeks before its perihelion passage.This comet was observed until 5 April 1976. [Kronk, Cometography: Volume 6].
Comet had its closest approach to the Earth on 19 April 1975 (1.838 au), about 2 weeks after its perihelion passage.
Solution given here is based on data spanning over 0.977 yr in a range of heliocentric distances: 1.26 au – 1.217 au (perihelion) – 4.44 au.
This Oort spike comet suffers large planetary perturbations during its passage through the planetary system; these perturbations lead to escape the comet from the solar system on hyperbolic orbit.
See also Królikowska 2020.

solution description
number of observations 54
data interval 1975 03 15 – 1976 03 07
data type significantly more measurements after perihelion (POST+)
data arc selection entire data set (STD)
range of heliocentric distances 1.26 au – 1.22 au (perihelion) – 4.44 au
detectability of NG effects in the comet's motion NG effects not determinable
type of model of motion GR - gravitational orbit
data weighting NO
number of residuals 108
RMS [arcseconds] 1.54
orbit quality class 2a
orbital elements (heliocentric ecliptic J2000)
Epoch 1975 04 18
perihelion date 1975 04 04.57927555 ± 0.00130219
perihelion distance [au] 1.21693964 ± 0.00000823
eccentricity 1.00140497 ± 0.00003100
argument of perihelion [°] 264.129797 ± 0.001145
ascending node [°] 157.908831 ± 0.000156
inclination [°] 55.243869 ± 0.000143
recip semi-major axis [10-6 au-1] -1,154.51 ± 25.47
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