Solar System
Dynamics &
Planetology
Group 		C/1913 Y1 Delavan



General description

data set of C/1913 Y1

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Comet C/1913 Y1 was discovered on 18 December 1913, about ten months before its perihelion passage, and was last seen on 19 September 1915 [Kronk, Cometography: Volume 3].

This comet made its closest approach to the Earth on 4 October 1914 (1.58 au), that is 9.5 months after its discovery and 3 weeks before perihelion passage.

Solution given below is based on data span over 1.72 yr in a range of heliocentric distances from 4.24 au through perihelion (1.10 au) to 4.26 au.

Comet suffered very slight planetary perturbations during its passage through the planetary system, and in the next passage through the perihelion it will enter the planet zone as Oort spike comet (see future barycentric orbits given below for both solutions: pure gravitational and non-gravitational).

Pure gravitational orbit determined from all available positional measurements (1006 observations) give 1a-class orbit, orbit given in Minor Planet Center is 1B-class (339 obs. used, the same arc of data; see MPC).

It was possible to determine the non-gravitational orbit for C/1913 Y1, the decrease of RMS is small (from 2.06 arcsec to 2.00 arcsec, see below) though only radial non-gravitational parameter was determined.

This comet was in the original sample of 19 comets used by Oort for his hypothesis on LPCs.

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.




Non–gravitational orbit — see below SSDP Cometary Note C1913Y1M1-001

SSDP Cometary Note C1913Y1A1-001

Comet C/1913 Y1 Delavan

number of observations 1006
number of residuals 1874
data interval 1913 Dec. 18 — 1915 Sep. 7
rms [arcsec] 2.06
orbit quality class 1a

Osculating orbital elements (heliocentric; ecliptic J2000.0)

Epoch (TT) 19141104.0 = JD 2420440.5
time of perihelion passage (TT) 19141026.767056 ± 0.000062
perihelion distance 1.10445641 ± 0.00000079
eccentricity 1.00016199 ± 0.00000143
argument of perihelion [deg] 97.467346 ± 0.000028
longitude of the ascending node [deg] 60.396107 ± 0.000024
inclination [deg] 68.038294 ± 0.000042
inverse semimajor axis [10-6 au-1] -146.67 ± 1.29

Note: Epoch is given in a format: yyyymmdd.d, time of perihelion passage in a format of yyyymmdd.dddddd.



data set of C1913 Y1

Figure caption: Six 2D-projections of the 6D space of original swarm (5001 VCs) of C/1913 Y1. Each density map is given in logarithmic scale presented on the right in the individual panel.
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Original orbital elements (barycentric; at 250 au from the Sun)

Epoch (TT) 16160310
time of perihelion passage (TT) 19141025.816829 ± 0.000055
perihelion distance 1.10070306 ± 0.00000079
eccentricity 0.99997563 ± 0.00000143
argument of perihelion [deg] 97.539554 ± 0.000028
longitude of the ascending node [deg] 60.475762 ± 0.000024
inclination [deg] 67.986327 ± 0.000043
inverse semimajor axis [10-6 au-1] 22.14 ± 1.30

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.



data set of C/1913 Y1

Figure caption: Six 2D-projections of the 6D space of future swarm (5001 VCs) of C/1913 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) 22131027
time of perihelion passage (TT) 19141026.924754 ± 0.000074
perihelion distance 1.10518625 ± 0.00000079
eccentricity 0.99993766 ± 0.00000143
argument of perihelion [deg] 97.460986 ± 0.000028
longitude of the ascending node [deg] 60.292940 ± 0.000024
inclination [deg] 67.982189 ± 0.000043
inverse semimajor axis [10-6 au-1] 56.41 ± 1.30


Future barycentric positions and velocities of 5001 VCs at 250 au from the Sun are given here   (data format), i.e. after leaving the planetary zone.



Non–gravitational orbit


SSDP Cometary Note C1913Y1M1-001

number of observations 1006
number of residuals 1860
data interval 1913 Dec. 18 — 1915 Sep. 7
rms [arcsec] 2.00
orbit quality class 1b

Osculating orbital elements (heliocentric; ecliptic J2000.0)

Epoch (TT) 19141104.0 = JD 2420440.5
time of perihelion passage (TT) 19141026.767012 ± 0.000062
perihelion distance 1.10444242 ± 0.00000218
eccentricity 1.00009618 ± 0.00000906
argument of perihelion [deg] 97.467000 ± 0.000059
longitude of the ascending node [deg] 60.396112 ± 0.000023
inclination [deg] 68.038602 ± 0.000059
inverse semimajor axis [10-6 au-1] -87.08 ± 8.20

Nongravitational parameters [10-8 au/day2] A1 = 1.240 ± 0.172 A2 = 0.0 (assumed) A3 = 0.0 (assumed)

Note: Epoch is given in a format: yyyymmdd.d, time of perihelion passage in a format of yyyymmdd.dddddd.



data set of C/1913 Y1

Figure caption: Six 2D-projections of the 6D space of original swarm (5001 VCs) of C/1913 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) 16151111
time of perihelion passage (TT) 19141025.817363 ± 0.000089
perihelion distance 1.10067114 ± 0.00000461
eccentricity 0.99994214 ± 0.00000465
argument of perihelion [deg] 97.541763 ± 0.000303
longitude of the ascending node [deg] 60.475772 ± 0.000024
inclination [deg] 67.986634 ± 0.000059
inverse semimajor axis [10-6 au-1] 52.57 ± 4.23

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.



data set of C/1913 Y1

Figure caption: Six 2D-projections of the 6D space of future swarm (5001 VCs) of C/1913 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) 22140224
time of perihelion passage (TT) 19141026.924707 ± 0.000072
perihelion distance 1.10515434 ± 0.00000461
eccentricity 0.99990403 ± 0.00000467
argument of perihelion [deg] 97.458874 ± 0.000300
longitude of the ascending node [deg] 60.292937 ± 0.000023
inclination [deg] 67.982497 ± 0.000059
inverse semimajor axis [10-6 au-1] 86.84 ± 4.23


Future barycentric positions and velocities of 5001 VCs at 250 au from the Sun are given here   (data format), i.e. after leaving the planetary zone.





Solar System Dynamics & Planetology Group, 2014. All rights reserved

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