C/1947 Y1

Solar System
Dynamics &
Planetology
Group

C/1947 Y1 Mrkos

General description

Comet C/1947 Y1 was discovered on 20 December 1947, that is two months before perihelion passage, and was last seen on 30 November 1948 [Kronk, Cometography: Volume 4].

This comet made its closest approach to the Earth on 17 February 1948 (1.674 au), that is almost at the moment of perihelion passage.

Solution given below is based on data span over 0.890 yr in a range of heliocentric distances from 1.589 au through perihelion (1.500 au) to 3.848 au.

Comet suffered slight planetary perturbations during its passage through the planetary system, and it will enter the planet zone as Oort spike comet in the next perihelion passage (see future barycentric orbit given below).

More details in Królikowska et al. 2014

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 C1947Y1A5-001

Comet C/1947 Y1 Mrkos

number of observations	124
number of residuals	204
data interval	1948 Jan. 10 — 1948 Nov. 30
rms [arcsec]	1.22
orbit quality class	1b

Osculating orbital elements (heliocentric; ecliptic J2000.0)

Epoch (TT)	19480219.0	= JD 2432600.5
time of perihelion passage (TT)	19480216.691915	± 0.000266
perihelion distance	1.49955491	± 0.00000327
eccentricity	1.00108229	± 0.00001286
argument of perihelion [deg]	61.923925	± 0.000215
longitude of the ascending node [deg]	199.300972	± 0.000072
inclination [deg]	77.533200	± 0.000061
inverse semimajor axis [10^-6 au^-1]	-721.74	± 8.58

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/1947 Y1. Each density map is given in logarithmic scale presented on the right in the individual panel.
The same figure in the new window

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

Epoch (TT)	16481028
time of perihelion passage (TT)	19480215.276061	± 0.000370
perihelion distance	1.49138818	± 0.00000319
eccentricity	0.99995691	± 0.00001267
argument of perihelion [deg]	62.089047	± 0.000218
longitude of the ascending node [deg]	199.256479	± 0.000073
inclination [deg]	77.586851	± 0.000061
inverse semimajor axis [10^-6 au^-1]	28.89	± 8.49

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.

Figure caption: Six 2D-projections of the 6D space of future swarm (5001 VCs) of C/1947 Y1. Each density map is given in logarithmic scale presented on the right in the individual panel.
The same figure in the new window

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

Epoch (TT)	22471009
time of perihelion passage (TT)	19480216.304140	± 0.000210
perihelion distance	1.49784258	± 0.00000338
eccentricity	0.99991866	± 0.00001273
argument of perihelion [deg]	61.829573	± 0.000217
longitude of the ascending node [deg]	199.327504	± 0.000072
inclination [deg]	77.567907	± 0.000061
inverse semimajor axis [10^-6 au^-1]	54.31	± 8.50