(2012 TQ236) vs 341874 (2008 GB53)

(2012 TQ236) vs 341874 (2008 GB53)

This is another interesting couple (same simulation approach described in the previous post).

(2012 TQ236)

Classification: Main-belt Asteroid          SPK-ID: 3612103

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

[ show orbit diagram ]

Orbital Elements at Epoch 2458000.5 (2017-Sep-04.0) TDB Reference: JPL 6 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .1666400181863286 5.5861e-06 a 2.181322170293682 2.3565e-06 au q 1.817826604165701 1.4148e-05 au i 3.706000259833047 2.3889e-05 deg node 130.8866173415038 0.00037736 deg peri 225.066713022466 0.0031505 deg M 207.0510430328395 0.0025163 deg tp 2458500.444927002519 (2019-Jan-16.94492700) 0.0088584 JED period 1176.73358020709 3.22 0.0019068 5.221e-06 d yr n .3059316110760132 4.9574e-07 deg/d Q 2.544817736421663 2.7491e-06 au

Orbit Determination Parameters    # obs. used (total)      25      data-arc span      1078 days (2.95 yr)      first obs. used      2012-09-23      last obs. used      2015-09-06      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      3      fit RMS      .65133      data source      ORB      producer      Otto Matic      solution date      2017-Apr-07 17:13:15   Additional Information  Earth MOID = .814749 au   Jupiter MOID = 2.88145 au   T_jup = 3.660

341874 (2008 GB53)

Classification: Main-belt Asteroid          SPK-ID: 2341874

[ Ephemeris | Orbit Diagram | Orbital Elements | Physical Parameters | Discovery Circumstances ]

[ show orbit diagram ]

Orbital Elements at Epoch 2458000.5 (2017-Sep-04.0) TDB Reference: JPL 4 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .1669528069531998 1.1233e-07 a 2.180875946944555 3.0388e-08 au q 1.816772585985444 2.5263e-07 au i 3.706556681959036 1.2083e-05 deg node 130.8943547687225 0.0001365 deg peri 225.0440620302201 0.00014182 deg M 182.8634290772902 3.7363e-05 deg tp 2458579.329428649479 (2019-Apr-05.82942865) 0.00013018 JED period 1176.372519962207 3.22 2.4587e-05 6.732e-08 d yr n .306025509684267 6.3962e-09 deg/d Q 2.544979307903666 3.5462e-08 au

Orbit Determination Parameters    # obs. used (total)      78      data-arc span      5842 days (15.99 yr)      first obs. used      2001-02-02      last obs. used      2017-01-31      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      fit RMS      .48759      data source      ORB      producer      Otto Matic      solution date      2017-Apr-10 08:47:34   Additional Information  Earth MOID = .813692 au   Jupiter MOID = 2.88132 au   T_jup = 3.660

Simulation results ((note, Time 0 is JD 0 --> 4713 B.C.)

Kind Regards,
Alessandro Odasso

(111298) = 2001 XZ55 versus 2008 YL20

See an update about this case received on Dec 10th: look at this MPML msg.



===============================================
I am looking again at these two asteroids.

A couple of years ago, as clearly explained by Bill Gray (see MPML msg ), it was a bit too early to make meaningful simulations trying to go back in the past as far as about 25000 years ago.

Now the orbit uncertaintly of asteroid 2008 YL20 has improved from +/- 1.62e-6 degrees /day to +/-1.1568e-08 degrees/day.

I tried a new simulation to investigate the possibility that these two asteroids separated in the past and I got a new result consisting in a nominal distance of about 4000 km, relative velocity about 15 cm/s. This event occurred about 34000 years ago.

The uncertainty is 1.1568e-08 * 365 * 34000 = 0.14 degrees that at an average distance of 2.39 AU corresponds to an uncertainty of about 0.0057 AU (i.e. three time the moon-earth distance).

So ... on one side no proof that these asteroids separated but it seems to me that this pair is still interesting.

More details looking the JPL Small Body Data:

(111298) = 2001 XZ55
Orbital Elements at Epoch 2457200.5 (2015-Jun-27.0) TDB
Reference: JPL 11 (heliocentric ecliptic J2000)

Element	Value	Uncertainty (1-sigma)	Units
e	.1837905901861221	6.7074e-08
a	2.391320808768463	2.2177e-08	AU
q	1.951818546000553	1.6999e-07	AU
i	3.192061836722895	7.0356e-06	deg
node	111.491991193275	0.00011791	deg
peri	297.8338388091076	0.0001197	deg
M	257.5887075379197	2.2491e-05	deg
tp	2457584.738198736595 (2016-Jul-15.23819874)	8.7199e-05	JED
period	1350.688466278188 3.70	1.879e-05 5.144e-08	d yr
n	.2665307426456207	3.7078e-09	deg/d
Q	2.830823071536374	2.6253e-08	AU

2008 YL20
Orbital Elements at Epoch 2457200.5 (2015-Jun-27.0) TDB
Reference: JPL 8 (heliocentric ecliptic J2000)

Element	Value	Uncertainty (1-sigma)	Units
e	.1837937583380851	5.5869e-07
a	2.391150352530784	6.9177e-08	AU
q	1.951671842487714	1.3831e-06	AU
i	3.193600462494826	1.3927e-05	deg
node	111.4717983197325	0.00025271	deg
peri	298.0606134273407	0.00030036	deg
M	320.5524746963916	0.00012064	deg
tp	2457348.487835047940 (2015-Nov-21.98783505)	0.00045708	JED
period	1350.544050792078 3.70	5.8608e-05 1.605e-07	d yr
n	.2665592431352864	1.1568e-08	deg/d
Q	2.830628862573854	8.1891e-08	AU

Mercury Simulator Results

Simulation parameters:

 algorithm (MVS, BS, BS2, RADAU, HYBRID etc) = bs2
 start time (days)= 2457387.5
 stop time (days) = -17.3d6
 output interval (days) = 20
 timestep (days) = 0.1
 accuracy parameter=1.d-12

The result shown as a graph (done with R package):

Kind Regards,
Alessandro Odasso



      Mercury Simulator - Mercury6
      J.E.Chambers (1999) ``A Hybrid
      Symplectic Integrator that Permits Close Encounters between
      Massive Bodies''. Monthly Notices of the Royal Astronomical
      Society, vol 304, pp793-799.

421781 (2014 QG22) vs 53576 (2000 CS47)

These two asteroids are a potentially interesting couple.
I do not know if this couple is already known and if it is really a couple with a common origin.

Let's look at the JPL data, showing very similar orbital parameters:
421781 (2014 QG22)
Orbital Elements at Epoch 2457200.5 (2015-Jun-27.0) TDB
Reference: JPL 5 (heliocentric ecliptic J2000)

Element	Value	Uncertainty (1-sigma)	Units
e	.1415490034245739	7.6497e-08
a	2.219666740174171	5.0262e-08	AU
q	1.905475125167845	1.6225e-07	AU
i	5.547751979163497	1.1933e-05	deg
node	270.894647775993	0.00023172	deg
peri	334.1685226014454	0.00025596	deg
M	170.5342535281013	0.00011344	deg
tp	2456628.311384753553 (2013-Dec-01.81138475)	0.00037629	JED
period	1207.897517520007 3.31	4.1027e-05 1.123e-07	d yr
n	.2980385295758646	1.0123e-08	deg/d
Q	2.533858355180498	5.7376e-08	AU

 Orbit Determination Parameters

# obs. used (total)      49      data-arc span      3697 days (10.12 yr)      first obs. used      2004-08-14      last obs. used      2014-09-28      planetary ephem.      DE431      SB-pert. ephem.      SB431-BIG16      condition code      0      fit RMS      .55494      data source      ORB      producer      Otto Matic      solution date      2015-Jan-08 13:35:22

Additional Information

Earth MOID = .893565 AU

T_jup = 3.631

53576 (2000 CS47)
Orbital Elements at Epoch 2457200.5 (2015-Jun-27.0) TDB
Reference: JPL 11 (heliocentric ecliptic J2000)

Element	Value	Uncertainty (1-sigma)	Units
e	.1413172303277337	5.195e-08
a	2.219866104654218	1.5604e-08	AU
q	1.906160775046069	1.1284e-07	AU
i	5.548153406788004	6.1614e-06	deg
node	270.899183954788	6.9605e-05	deg
peri	334.2072656882382	7.5251e-05	deg
M	151.5995810376835	2.9164e-05	deg
tp	2456691.773809093385 (2014-Feb-03.27380909)	9.8063e-05	JED
period	1208.060256319952 3.31	1.2737e-05 3.487e-08	d yr
n	.2979983805581422	3.142e-09	deg/d
Q	2.533571434262367	1.7809e-08	AU

Orbit Determination Parameters

# obs. used (total)      610      data-arc span      7436 days (20.36 yr)      first obs. used      1994-07-08      last obs. used      2014-11-16      planetary ephem.      DE431      SB-pert. ephem.      SB431-BIG16      condition code      0      fit RMS      .49974      data source      ORB      producer      Otto Matic      solution date      2015-Mar-09 16:42:10

Additional Information

Earth MOID = .894238 AU

T_jup = 3.631

 I tried to run the Mercury simulator (BS2 integrator, timestep 1 day) with the nominal parameters, with this result (graph done with the R package)

Kind Regards,
Alessandro Odasso