Comet 311P and asteroid 2003 QO120

 see MPML message

 

Backward integration result

Asteroid 2006 XL5 - likely cometary origin

The orbits of asteroid 2006 XL5 and comet 75D/Kohoutek are vaguely similar:

                        a         e        i       om        w       q
       (2006 XL5) 3.723259 0.5154009 4.526352 274.0060 175.1221   1.804288
   75D/Kohoutek   3.543147 0.4963074 5.907209 269.6861 175.8017   1.784657

It is not clear to me if asteroid 2006 XL5 with a diameter about 1.6 km might be an old fragment of the lost comet that was estimated to be about 4.6 km in diameter.

I tried a backward simulation but there is no clear indication that this is the case.

What is interesting is that 2006 XL5 might have a cometary origin itself (the MOID with jupiter is about 0.16 AU).

Clones generation

I generated 100 clones of asteroid 2006 XL5 trying to achieve the same mean orbital parameters (and uncertainty).

	Clones			2006 XL5
	mean	sd		mean	sd
q	1.80428798284277	5.24177295141045e-07		1.80428796355464	5.2592e-07
e	0.515400864913161	1.29060036714178e-07		0.515400869129902	1.2918e-07
i	4.52635127581998	7.48101264185302e-06		4.52635163398884	7.4744e-06
peri	175.122110003296	0.000109392746353213		175.122116165405	0.00010898
node	274.006039830699	9.87233639993821e-05		274.006030101048	9.8249e-05
tp	2459319.93402565	0.000249555965707767		2459319.93400848	0.00024939

 

Backward simulation config parameters

Mercury6 software - package version 6 by John E. Chambers

)O+_06 Integration parameters  (WARNING: Do not delete this line!!)
) Lines beginning with `)' are ignored.
)---------------------------------------------------------------------
) Important integration parameters:
)---------------------------------------------------------------------
 algorithm (MVS, BS, BS2, RADAU, HYBRID etc) = BS
 start time (days)= 2459806.5
 stop time (days) = -1d8
 output interval (days) = 100
 timestep (days) = 0.05
 accuracy parameter=1.d-12
...

 ejection distance (AU)= 100

based on this configuration, any clone coming into the solar system from a distance greater than 100 AU is considered to have a "cometary origin".

Simulation results

75% of the clones have a cometary origin

 ddd

(76000) Juliuserving and 2020 YQ9

Backward integration performed with Mercury6 integrator using the nominal orbit paameters.

Main integration parameters:

)---------------------------------------------------------------------
) Important integration parameters:
)---------------------------------------------------------------------
 algorithm (MVS, BS, BS2, RADAU, HYBRID etc) = BS
 start time (days)= 2459671.5
) stop time (days) = 102458000.5
 stop time (days) = -1d8
 output interval (days) = 100
 timestep (days) = 0.05
 accuracy parameter=1.d-12
)---------------------------------------------------------------------
) Integration options:
)---------------------------------------------------------------------
 stop integration after a close encounter = no
 allow collisions to occur = no
 include collisional fragmentation = no
 express time in days or years = years
 express time relative to integration start time = no
 output precision = medium
 < not used at present >
 include relativity in integration= no
 include user-defined force = no

 

Integration result

A/2019 O2

Following this message (and related responses) from Pieter-Jan Dekelver,  working at the Observatory Grömme - MPC: D09 – M09in MPML list, I tried a backward simulation looking at a few centuries in the past.

It seems to be an object can get as far as 106 AU from the sun in repeating cycles (about 450-500 years).

r (sun distance)

Orbital parameters

Asteroid Families - Cluster Dendogram

This wiki page displays a table of asteroid families.

Out of curiosity, I imported the table in R and I run a hierarchical clustering algorithm on the table taking into account the average orbital parameters a,e,i of the various families.

Then I plotted the resulting dendogram (rotated 90 deg to facilitate reading):

100499 (1996 XP) and 2014 OT426

 Backward integration with Mercury6 based on nominal orbital parameters:

)---------------------------------------------------------------------
) Important integration parameters:
)---------------------------------------------------------------------
 algorithm (MVS, BS, BS2, RADAU, HYBRID etc) = BS
 start time (days)= 2459671.5
) stop time (days) = 102458000.5
 stop time (days) = -1d8
 output interval (days) = 100
 timestep (days) = 0.05
 accuracy parameter=1.d-12

Result

 P.S.

Following a comment from Afrien Coffinet (what happened at about year -15000 ?), I plotted the orbital parameters of the asteroids that are almost overlapped, at least at the scale of the graphics.

Around that date: 

• eccentricity reached the minimum value as confirmed by q and Q, 
• inclination reached the minimum value, 
• the argument of perihelium had a "disturbance" (encounter with a big planet? - not clear)
  
• the ascending node reached the maximum vaue)