C/2014 OG392 - about its cometary origin

A coma was recently detected as far as 400,000 km from centaur 2014 OG392 by NAU researchers (click here to access their paper).

Following this discovery, the centaur was given a comet designation: C/2014 OG392 

C/2014 OG392 (PANSTARRS)

Classification: Chiron-type Comet          SPK-ID: 1003735

[ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters ]

[ show orbit diagram ]

Orbital Elements at Epoch 2457785.5 (2017-Feb-01.0) TDB Reference: JPL 14 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .1804389828275273 7.4417e-06   a 12.150254615787 0.00018697 au q 9.957875031818922 6.704e-05 au i 9.046144236347711 4.6644e-05 deg node 145.8645384329216 0.00015579 deg peri 254.7881434680575 0.0027215 deg M 318.4435044274125 0.0027357 deg tp 2459571.218143409214 (2021-Dec-22.71814341) 0.076746 TDB period 15469.50778138701 42.35 0.35708 0.0009776 d yr n .0232715872468259 5.3717e-07 deg/d Q 14.34263419975507 0.00022071 au

Orbit Determination Parameters    # obs. used (total)      213      data-arc span      3371 days (9.23 yr)      first obs. used      2011-07-27      last obs. used      2020-10-18      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      3      norm. resid. RMS      .22122      source      ORB      producer      Otto Matic      solution date      2020-Oct-26 19:43:48   Additional Information  Earth MOID = 8.97742 au   Jupiter MOID = 5.06363 au   T_jup = 3.397

I tried to investigate the cometary nature running a backward integration using Mercury6 software by E. Chambers.

I generated 100 clones trying to achieve the same nominal orbital parameters and uncertainty as above.

	Clones			Target
	mean	sd		mean	sd
q	9.95787410878	6.694624e-05		9.95787503182	6.704e-05
e	0.18043892764	7.50991e-06		0.18043898283	7.4417e-06
i	9.04614599334	4.699782e-05		9.04614423635	4.6644e-05
peri	254.78819470552	0.00271470415		254.78814346806	0.0027215
node	145.86454031167	0.0001548109		145.86453843292	0.00015579
tp	2459571.21974672	0.07635106812		2459571.21814341	0.076746

Simulation parameters

integration algorithm: Bulirsch-Stoer

ejection distance from the solar system: 100 au

simulation start time: 2020 A.D.

simulation stop time: -1d8 (about -274K years BC)

Simulation results

A "true" cometary origin is confirmed for 29 clones, in fact, they entered the solar system from a distance greater than 100 au according to this arrival time distribution

In order to read the following plots, you need to know that:

the simulated time is divided into 50 intervals , in every interval and for every clone I have calculated the min perihelium and then I have plotted the interquantile distribution in that interval.

Similar approach for max aphelium, max eccentricity, ... etc.

Perihelium q

Aphelium Q

Eccentricity e

Inclination i

Peri w

Node om

Kind Regards,

Alessandro Odasso

P/2020 F1 Leonard

In an interesting MPML message, Sam Deen who found precovery images of this comet has shown that P/2020 F1 Leonard had a close encounter with Saturn in May 1936.

The close approach has been confirmed by Denis Denisenko and also by Syuichi Nakano that mentioned it in CBET 4737 (see by Brian Skiff's note ).

Denis Denisenko has also shown that what was previously thought to be a galaxy known as SDSS J113712.61+064629.0 was in fact the same comet!

It seems that the close approach with Saturn occurred at less than 1 mln km distance, quoting his words "coming to the point where Titan should be probably taken into account".

Due to this possibility, I am not sure if the below simulation can be reliable because even if all planets (including Uranus and  ... well ... also former planet Pluto) were taken into account, I did not add Titan.

As suggested by Denis Denisenko, Titan should probably be taken into account because according to the simulation results shown below, the close encounter with Saturn could have occurred at a distance much much lower than 1 mln km... I really wonder if what shown below makes sense!.

I generated 100 clones trying to achieve the same orbital parameters reported in JPL Small-Body Database.

[ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Close-Approach Data ]

[ show orbit diagram ]

Orbital Elements at Epoch 2458881.5 (2020-Feb-02.0) TDB Reference: JPL 1 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .4167294137837126 3.2093e-05 a 6.828937975484302 0.00042644 au q 3.983118656195396 3.0111e-05 au i 5.435887012485813 9.3305e-05 deg node 136.6570425356324 0.0006689 deg peri 8.692144095904881 0.0050162 deg M 8.65720560933176 0.0015783 deg tp 2458724.751493851214 (2019-Aug-29.25149385) 0.036878 TDB period 6518.207463241558 17.85 0.61055 0.001672 d yr n .05522990822709547 5.1733e-06 deg/d Q 9.674757294773208 0.00060415 au

Orbit Determination Parameters    # obs. used (total)      85      data-arc span      443 days (1.21 yr)      first obs. used      2019-01-03      last obs. used      2020-03-21      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      4      norm. resid. RMS      .44614      source      ORB      producer      Otto Matic      solution date      2020-Mar-25 18:12:07   Additional Information  Earth MOID = 2.99577 au   Jupiter MOID = .379473 au   T_jup = 2.835

P/2020 F1 (Leonard)

Classification: Jupiter-family Comet          SPK-ID: 1003664

Clones simulated

	Clones			Target
	mean	sd		mean	sd
q	3.98312397488	3.011474e-05		3.9831186562	3.0111e-05
e	0.41673463882	3.223462e-05		0.41672941378	3.2093e-05
i	5.43588826127	9.318419e-05		5.43588701249	9.3305e-05
peri	8.69166111114	0.00503993969		8.6921440959	0.0050162
node	136.65698385154	0.00067172871		136.65704253563	0.0006689
tp	2458724.74745393	0.03690546666		2458724.75149385	0.036878

Simulation Details

Mercury6 simulator by John E. Chambers.

)---------------------------------------------------------------------
) 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


Simulation Results

The comet P/2020 F1 Leonard - taking into account its nominal params, seems to have entered the solar system (conventional distance 100 AU) about 45K years ago while the first clones did it even earlier about 10-20K years ago.

Considering the close encounter with Saturn:

• the "nominal" comet had the encounter on May 12, 1936 (distance 0.0046 AU - about  700000 km). Note that the simulation step was 0.05 days, I wonder if this "granularity" may explain the difference compared with the real nominal distance that was achieved on May 7th/8th.

note:  if you use the Horizons system via telnet interface
( telnet horizons.jpl.nasa.gov 6775 ), a similar date is found:

Close-approach results:

Time (JDTDB): 2428300.80754

Date (TDB): 1936 May 12.30754

Body: Satrn

CA Dist : .004603

MinDist : .000000

MaxDist: .022999

Vrel: 10.676

•  more in general, 99 clones (including the nominal comet) had the close encounter with Saturn in 1936, the other one had it in 1937.

The minimum distance from Saturn was 0.0000727 AU (about 11000 Km ???).




Can the simulator manage such a situation? 
Not clear to me ... however, out of curiosity, let's say for a moment ... yes!
In the following plots we can clearly see the "orbital disruption" suffered by the comet when it passed near Saturn in the 1930's.

 

 

 

 

 

 

Kind Regards,

Alessandro Odasso