2021 KT21 and 2004 GZ13

Backward simulation performed with Mercury6 ``A Hybrid Symplectic Integrator that Permits Close Encounters between Massive Bodies''. Monthly Notices of the Royal Astronomical Society, vol 304, pp793-799. 

Simulation based on nominal orbital paramters (21st March 2024)

Simulation 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)= 2460309.50000 

 stop time (days) = -1e8

 output interval (days) = 100

 timestep (days) = 0.05

 accuracy parameter=1.d-12

Simulation Result

Following a comment from Adrien Coffinet, here is a forward simulation to show that as correctly guessed, the two asteroids might be again in a similar orbital configuration about 20K years from now:

Hungaria - 2010 MA151 and 2017 BD92

 Backward simulation with Mercury6 (integrator BS, output every 100 days)

2005 UW252 and 2008 SO356

 Backward simulation based on nominal orbital parameters (Mercury6 simulator, BS integrator, output every 100 days):

2022 QV223 and 2012 SZ58

 Potentially interesting couple (common orgin?)

(294003) 2007 TN89 versus 2020 OJ94

This is a potentially interesting couple (future studies may confirm if these two asteroids separated from a common body or not).

Clones Generation

I generated 100 clones for each asteroid trying to achieve the same orbital parameters distribution as the real asteroids (data from JPL - Small-Body Database Lookup)

2007 TN89

	Clones			Target
	mean	sd		mean	sd
q	2.68037919449023	1.02422758252756e-07		2.68037919030732	1.0278e-07
e	0.0332834075416157	3.72583687170622e-08		0.0332834084098655	3.723e-08
i	4.87064454567147	4.91926754962451e-06		4.87064467562245	4.9051e-06
peri	119.704478491351	9.26537293487407e-05		119.70447923946	9.1341e-05
node	165.541938400386	5.00609236406486e-05		165.541939646563	4.9617e-05
tp	2460623.98663213	0.000350292088224234		2460623.98664169	0.00035377

2020 OJ94

	Clones			Target
	mean	sd		mean	sd
q	2.68031516329671	5.80931724850316e-07		2.68031508062098	5.8247e-07
e	0.0332987005798029	2.12854522457715e-07		0.0332987315205281	2.1173e-07
i	4.8708823913187	1.03347748674252e-05		4.87088223032125	1.0457e-05
peri	119.702555842119	0.000210522154416148		119.70257257331	0.00021113
node	165.541174514102	0.000118615308715787		165.541191321507	0.00011803
tp	2460627.54541522	0.000804795345716826		2460627.54557597	0.00080474

Simulation

The backward simulationwas done with Mercury 6 software taking into account all planets + Ceres + Pallas + Vesta:

)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)= 2460125.5

 stop time (days) = -1d8

 output interval (days) = 100

 timestep (days) = 0.05

 accuracy parameter=1.d-12

Results

After the simulation finished, I compared all the 100x100=10^4 clone couples to determine the behaviour of the "best" couples sorting them by minimum relative velocity.

The top 10 couples behaved like this (relative distance in km, relative velocity in m/s):

           Year relative_Distance relative_Velocity

 1:  -79283.756          3578.058             0.008

 2: -167296.514         10004.868             0.008

 3: -144257.301          7417.041             0.009

 4: -101207.820          4225.343             0.009

 5:  -95159.236          4890.873             0.015

 6: -133453.520          5479.847             0.017

 7: -143202.385          4896.550             0.017

 8: -111727.954          6362.393             0.020

 9: -101200.975          5827.283             0.020

10: -225280.730         11845.825             0.020

The best couple (row 1) is this one:

2022 QB59 and 2022 RM50 and 2011 RF40

See this MPML message and related thread about this probable asteroid cluster.

Using Sam Deen's updated orbital elements, we get this result from a backward simulation performed with Mercury6 software:

2022 QB59 and 2022 RM50 are likely to have separated from a common parent body.

 

 

Best wishes,

Alessandro Odasso