C/1919 Q2

Solar System
Dynamics &
Planetology
Group

C/1919 Q2 Metcalf

General description

Comet C/1919 Q2 was discovered on 23 August 1919, about 3.5 months before its perihelion passage, and was last seen on 17 February 1920 [Kronk, Cometography: Volume 3].

This comet made its closest approach to the Earth on 29 November 1919 (1.90 au), that is eight days before its perihelion passage.

Solution given below is based on data span over 0.444 yr in a range of heliocentric distances from 1.951 au through perihelion (1.115 au) to 1.446 au.

Comet suffered a very slight planetary perturbations during its passage through the planetary system, however, they led to escape the comet from the planetary zone on a hiperbolic orbit (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 C1919Q2A5-001

Comet C/1919 Q2 Metcalf

number of observations	275
number of residuals	498
data interval	1919 Aug. 25 — 1920 Feb. 3
rms [arcsec]	2.58
orbit quality class	2a

Osculating orbital elements (heliocentric; ecliptic J2000.0)

Epoch (TT)	19191118.0	= JD 2422280.5
time of perihelion passage (TT)	19191207.809648	± 0.002096
perihelion distance	1.11527223	± 0.00002732
eccentricity	1.00020566	± 0.00007480
argument of perihelion [deg]	185.753567	± 0.002470
longitude of the ascending node [deg]	122.098062	± 0.000560
inclination [deg]	46.381870	± 0.000174
inverse semimajor axis [10^-6 au^-1]	-184.40	± 67.07

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/1919 Q2. 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)	16210324
time of perihelion passage (TT)	19191207.325501	± 0.002308
perihelion distance	1.11815172	± 0.00002760
eccentricity	0.99996124	± 0.00007520
argument of perihelion [deg]	185.698259	± 0.002474
longitude of the ascending node [deg]	122.175370	± 0.000564
inclination [deg]	46.404177	± 0.000178
inverse semimajor axis [10^-6 au^-1]	34.67	± 67.26

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/1919 Q2. 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)	22171225
time of perihelion passage (TT)	19191208.123284	± 0.002011
perihelion distance	1.11801549	± 0.00002841
eccentricity	1.00003007	± 0.00007525
argument of perihelion [deg]	185.783020	± 0.002443
longitude of the ascending node [deg]	122.055357	± 0.000557
inclination [deg]	46.365671	± 0.000179
inverse semimajor axis [10^-6 au^-1]	-26.89	± 67.31