2010 RN221 and (458271) 2010 UM26

I have tried to link these two asteroids without success and also Peter Veres (MPC) has been so kind to check and he told me that no linkage can be done.

He added that "it might be worth investigating this case" to see if it is true that these objects have departed from each other.

If these objects are really different, something very strange might have occurred in year 2003.

 

Look at the result of a backward simulation that I tried:

Also using  JPL Horizons for the date 22-January-2003, look at the relative distance and velocity

(coherent with the simulation result):

Target body name: (2010 RN221)   

$$SOE

2452661.500000000 = A.D. 2003-Jan-22 00:00:00.0000 TDB 
 X =-8.920099855275528E+07 Y = 3.752091212286066E+08 Z =-1.906335678954402E+07
 VX=-1.836459849490381E+01 VY= 1.763251089208628E+00 VZ=-1.090280059553749E+00
 LT= 1.288015822532121E+03 RG= 3.861374293797964E+08 RR= 6.009551617298905E+00
$$EOE

Target body name: 458271 (2010 UM26) 
$$SOE
2452661.500000000 = A.D. 2003-Jan-22 00:00:00.0000 TDB 
 X =-8.920133310842243E+07 Y = 3.752083644498053E+08 Z =-1.906344797876614E+07
 VX=-1.836461372418546E+01 VY= 1.763243109436744E+00 VZ=-1.090279471456164E+00
 LT= 1.288013642446344E+03 RG= 3.861367758065227E+08 RR= 6.009570237326630E+00
$$EOE

Did these two objects separated from a common progenitor?

Best wishes,

Alessandro Odasso

 

2011 YO17 - Cometary Origin?

2011 YO17 - Backward simulation 

Simulation based on 100 clones:

	Clones			Target
	mean	sd		mean	sd
q	3.3457192543808	2.89972813116376e-07		3.34571929768682	2.8751e-07
e	0.184121058387053	7.17001427077198e-08		0.184121045157645	7.1351e-08
i	18.249168025204	9.19753172889254e-06		18.2491686171502	9.2211e-06
peri	165.624322571055	3.52571408153806e-05		165.624319088164	3.5024e-05
node	302.902335551023	2.30225190945596e-05		302.902339849507	2.2893e-05
tp	2458883.14050519	0.000193613119572893		2458883.14050091	0.00019246

the table above shows the orbital parameters distribution of the clones in comparison with the nominal (target) solution.

 

Simulation method

Mercury Integrator Package Version 6 by J. E. Chambers

 )---------------------------------------------------------------------
) Important integration parameters:
)---------------------------------------------------------------------
 algorithm (MVS, BS, BS2, RADAU, HYBRID etc) = BS
 start time (days)= 2459600.5
) 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

If a clone comes into the solar system from a distance greater than 100 AU, it is considered to have a cometary origin.

Simulation Results

73 out of 100 clones have a cometary origin:

 

In the following plots, the time has been divided into 50 slots and it is shown vertically for graphical reasons.

The 27  clones that did not come from a distance greater than 100 AU are flagged as being on an asteroid-like orbit, while the other are considered to be on a cometary-like orbit (the more you look in the past, the less clones are found because they were "ejected" in the backward simulation).

 

Perihelium

Aphelium

Eccentricity

Orbital Period

Orbit specific energy

Inclination

Argument of perihelium

Ascending node

Longitude

Best wishes,

Alessandro Odasso

2017 UE157 vs 2017 XW66

 2017 UE157 and 2017 XW66 might have separated from a common object.

Results of the backward integration done with Mercury6 (algorithm BS, output interval 100 days, timestep 0.05 days) using nominal orbital parameters read from JPL

 

Cheers,

Alessandro Odasso