astro: comet-like orbit

Its orbit has a Jupiter moid = 0.0060 AU

I generated 100 clones of 2021 CC40 in the last 10^8 days (i.e. from now back to about 280K years ago).
75 clones came into the solar system from a distance greater than 100 AU

From this point of view, it seems that 2021 CC40 is a good candidate for having a cometary origin.

More details here:

Clones Generation

	Clones		Target
	mean	sd	mean	sd
q	3.25399802390041	7.03707449970568e-05	3.25400084057019	7.0403e-05
e	0.241134331789963	1.59398555200895e-05	0.241133698559336	1.5947e-05
i	12.9796232392302	6.18646863798976e-05	12.9796210051976	6.1886e-05
peri	328.501490543462	0.00855370237432572	328.501160286746	0.008554
node	235.614402285421	0.000361242956610133	235.61440679467	0.00036124
tp	2459672.09000109	0.0444299088063099	2459672.08824673	0.044429

Mercury6 Simulation

)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)= 2459671.5
) stop time (days) = 102458000.5
 stop time (days) = -1d8
 output interval (days) = 100
 timestep (days) = 0.05
 accuracy parameter=1.d-12

...

 ejection distance (AU)= 100

Results

In the following plots, time is displayed on the vertical axis in order to have more space. The simulation time has been divided into 50 slots and for every slot the relevant orbital parameter distribution (inter-quartile) of all existing clones is shown.

This asteroid belongs to the list of Asteroids with comet-like orbit.

From JPL Small-Body Database:

(2019 WU5)

Classification: Outer Main-belt Asteroid SPK-ID: 3893764

[ show orbit diagram ]

Orbital Elements at Epoch 2459000.5 (2020-May-31.0) TDB
Reference: JPL 7 (heliocentric ecliptic J2000)

Element	Value	Uncertainty (1-sigma)	Units
e	.1930697920316617	1.6908e-07
a	4.333585836868623	1.4656e-07	au
q	3.496901320593043	7.463e-07	au
i	72.04068464386691	2.1904e-05	deg
node	221.6645605674607	1.0021e-05	deg
peri	180.4193313645169	0.00041009	deg
M	357.4154880974056	0.00028294	deg
t_p	2459024.156231824573 (2020-Jun-23.65623182)	0.0025898	TDB
period	3295.107075458794 9.02	0.00016716 4.577e-07	d yr
n	.1092528988454421	5.5424e-09	deg/d
Q	5.170270353144202	1.7486e-07	au

Orbit Determination Parameters

# obs. used (total)	61
data-arc span	3329 days (9.11 yr)
first obs. used	2011-11-24
last obs. used	2021-01-04
planetary ephem.	DE431
SB-pert. ephem.	SB431-N16
condition code	0
norm. resid. RMS	.45354
source	ORB
producer	Otto Matic
solution date	2021-Jan-19 01:09:36

Additional Information

Earth MOID = 2.50565 au

Jupiter MOID = .257366 au

T_jup = 1.753

Clone Generation

I have generated 100 clones with same nominal orbital paramaters and uncertainty as listed in JPL.

	Clones		Target
	mean	sd	mean	sd
q	3.49690139144	7.4916e-07	3.49690132059	7.463e-07
e	0.19306977346	1.6869e-07	0.19306979203	1.6908e-07
i	72.04068365797	2.190239e-05	72.04068464387	2.1904e-05
peri	180.41934713818	0.00040883845	180.41933136452	0.00041009
node	221.6645589917	9.9937e-06	221.66456056746	1.0021e-05
tp	2459024.15632594	0.00257792331	2459024.15623182	0.0025898

Simulation

Mercury 6 simulator - Main integration parameters:

)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)= 2459000.5

stop time (days) = -1d8

output interval (days) = 100

timestep (days) = 0.05

accuracy parameter=1.d-12

...

ejection distance (AU)= 100

Results

37% of the clones (abbreviated as WU_<xx>) have a cometary orgin (i.e., they arrived into the solar system from a distance greater than 100 AU

Clone Year

1 WU_100 -56379

2 WU_13 -76730

3 WU_75 -78626

4 WU_60 -82278

5 WU_49 -89951

6 WU_65 -90759

7 WU_68 -104326

8 WU_23 -104646

9 WU_55 -112570

10 WU_61 -116290

11 WU_34 -121402

12 WU_12 -128031

13 WU_20 -128759

14 WU_6 -139418

15 WU_21 -140254

16 WU_5 -145159

17 WU_43 -148811

18 WU_26 -154109

19 WU_62 -154655

20 WU_50 -160938

21 WU_84 -172015

22 WU_88 -174160

23 WU_92 -181595

24 WU_14 -186024

25 WU_33 -188258

26 WU_72 -191679

27 WU_39 -198447

28 WU_99 -219044

29 WU_79 -219399

30 WU_2 -221567

31 WU_8 -225358

32 WU_31 -226367

33 WU_38 -227092

34 WU_52 -229987

35 WU_28 -231880

36 WU_76 -248039

37 WU_18 -261908

The same data are displayed below in a graphical form

In the simulation, there were also many clones that are not physically possible because they seem to have been generated by the sun (i.e., hit the sun in the backward simulation):

the sun was hit by WU_37 at -52591

the sun was hit by WU_64 at -57478

the sun was hit by WU_29 at -70918

the sun was hit by WU_9 at -71001

the sun was hit by WU_40 at -80609

the sun was hit by WU_22 at -84348

the sun was hit by WU_95 at -101285

the sun was hit by WU_11 at -110098

the sun was hit by WU_57 at -128350

the sun was hit by WU_66 at -152709

the sun was hit by WU_27 at -189078

the sun was hit by WU_80 at -190586

the sun was hit by WU_53 at -200575

the sun was hit by WU_41 at -219225

the sun was hit by WU_63 at -226575

the sun was hit by WU_85 at -239827

Looking in more detail at the clones that have a clear cometary origin, we find some that entered the solar system on a hyperbolic trajectory with V-infinity (km/s) as shown below:

Clone V-infinity

1: WU_100 16.108207

2: WU_21 13.756060

3: WU_31 11.663052

4: WU_55 11.590669

5: WU_72 9.704585

6: WU_60 8.068643

7: WU_92 7.018560

8: WU_68 6.375238

9: WU_65 5.577997

10: WU_50 5.496867

11: WU_84 4.518317

12: WU_99 3.747645

13: WU_79 1.179131

Orbital Parameters - Time plots

The simulation time is divided into slots.

In every slot and for every clone, you calculate the min perihelium distance, then you look at the distribution of the values plotting a segment showing the interquantile range.

(similar approach for the other orbital parameters).