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Monday, July 10, 2017

276353 (2002 UY20) vs 57202 (2001 QJ53)

276353 (2002 UY20) vs 57202 (2001 QJ53)

Same approach described in the previous posts.

276353 (2002 UY20)

Classification: Main-belt Asteroid          SPK-ID: 2276353
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 8 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .1562105639420963 6.3914e-08
a 2.337601777404309 2.6617e-08 au
q 1.972443685483935 1.5861e-07 au
i 4.252343536114911 6.8871e-06 deg
node 23.41388838094758 0.0001045 deg
peri 35.95235952421835 0.00010784 deg
M 38.09017324814934 2.7256e-05 deg
tp 2457862.377424660816
(2017-Apr-18.87742466)
9.8187e-05 JED
period 1305.431897045054
3.57
2.2296e-05
6.104e-08
d
yr
n .2757708010773199 4.7101e-09 deg/d
Q 2.702759869324683 3.0775e-08 au
Orbit Determination Parameters
   # obs. used (total)      115  
   data-arc span      5111 days (13.99 yr)  
   first obs. used      2002-10-28  
   last obs. used      2016-10-25  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   fit RMS      .70803  
   data source      ORB  
   producer      Otto Matic  
   solution date      2017-Apr-10 16:21:05  

Additional Information
 Earth MOID = .986707 au 
 Jupiter MOID = 2.62843 au 
 T_jup = 3.546 

57202 (2001 QJ53)

Classification: Main-belt Asteroid          SPK-ID: 2057202
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 17 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .1557724906162496 4.4578e-08
a 2.338080038545681 1.0974e-08 au
q 1.973871487681283 1.03e-07 au
i 4.250626760813153 5.0566e-06 deg
node 23.42499161765863 6.5966e-05 deg
peri 36.16096420351912 6.8003e-05 deg
M 103.6361139081139 1.6156e-05 deg
tp 2457624.579415793553
(2016-Aug-24.07941579)
5.793e-05 JED
period 1305.832544380318
3.58
9.1935e-06
2.517e-08
d
yr
n .275686190813109 1.9409e-09 deg/d
Q 2.702288589410078 1.2683e-08 au
Orbit Determination Parameters
   # obs. used (total)      743  
   data-arc span      16797 days (45.99 yr)  
   first obs. used      1971-03-25  
   last obs. used      2017-03-20  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   fit RMS      .57656  
   data source      ORB  
   producer      Otto Matic  
   solution date      2017-Apr-11 18:07:27  

Additional Information
 Earth MOID = .988199 au 
 Jupiter MOID = 2.62768 au 
 T_jup = 3.546 

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



Kind Regards,
Alessandro Odasso

(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

Monday, June 26, 2017

481085 (2005 SA135) vs 21028 (1989 TO)

I wonder if these two mars crossing asteroids might have generated from a common body.

The asteroid 21028 (1989 TO) is itself a recognized binary asteroid (Pravec et others). The rotation period is 3.6644 hours.

This is the result of my simulation (note, Time 0 is JD 0 --> 4713 B.C.) :



Approach
  • download orbital prameters from JPL Small-Body Database
  • perform simulation using Mercury6 software by John Chambers
  • establish a threshold rule (distance and relative velocity) for  stating that a couple of asteroids might have a common origin
  • analyze results and plot using R programming environment

Orbital parameters


481085 (2005 SA135)

Classification: Mars-crossing Asteroid          SPK-ID: 2481085
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 10 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .2984405268289324 8.8599e-08
a 2.334110493987974 2.4417e-08 au
q 1.637517328485263 1.9453e-07 au
i 21.80096788876684 1.6384e-05 deg
node 340.5993513550984 1.7134e-05 deg
peri 98.81719065459441 6.9324e-05 deg
M 91.04532224832778 4.774e-05 deg
tp 2457671.090833414662
(2016-Oct-09.59083341)
0.00017073 JED
period 1302.508432528503
3.57
2.0438e-05
5.596e-08
d
yr
n .2763897653247032 4.3369e-09 deg/d
Q 3.030703659490684 3.1704e-08 au
Orbit Determination Parameters
   # obs. used (total)      243  
   data-arc span      4215 days (11.54 yr)  
   first obs. used      2005-09-11  
   last obs. used      2017-03-27  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   fit RMS      .52233  
   data source      ORB  
   producer      Otto Matic  
   solution date      2017-Apr-09 05:41:20  

Additional Information
 Earth MOID = .79863 au 
 Jupiter MOID = 2.52193 au 
 T_jup = 3.416 

21028 (1989 TO)

Classification: Mars-crossing Asteroid          SPK-ID: 2021028
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 17 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .2998944450657227 5.4262e-08
a 2.332990251676451 1.1059e-08 au
q 1.633339434806201 1.2906e-07 au
i 21.78593156617378 8.7621e-06 deg
node 340.5615644130669 1.7944e-05 deg
peri 98.59272923713611 2.2979e-05 deg
M 263.6251062251222 1.3504e-05 deg
tp 2458348.940978486229
(2018-Aug-18.44097849)
4.9949e-05 JED
period 1301.570848400155
3.56
9.2546e-06
2.534e-08
d
yr
n .2765888621756544 1.9666e-09 deg/d
Q 3.032641068546701 1.4375e-08 au
Orbit Determination Parameters
   # obs. used (total)      751  
   data-arc span      9775 days (26.76 yr)  
   first obs. used      1989-10-04  
   last obs. used      2016-07-09  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   fit RMS      .43258  
   data source      ORB  
   producer      Otto Matic  
   solution date      2017-Apr-05 23:49:35  

Additional Information
 Earth MOID = .795177 au 
 Jupiter MOID = 2.52435 au 
 T_jup = 3.417 

Simulation setup

Let's try to investigate the last 1d8 days (about 274000 years), output interval every 100 days.

N-body algorithm:  Conservative Bulirsch-Stoer

This simulation will generate a file with almost 1e6 lines per asteroid.

)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) = bs2
 start time (days)= 2457800.5
 stop time (days) = -1d8
 output interval (days) = 100
 timestep (days) = 0.1
 accuracy parameter=1.d-12


Threshold rule
The following two conditions must be true at the same timestep:
  • distance less that 0.0020 AU (about 1 lunar distance)
  • relative velocity less than 1 meter/s

R custom program
I developed a small custom program to quickly analyze the results.

This program loads the output of the Mercury6 simulator (for every asteroid: a file with Time plus X,Y,Z and VX, VY, VZ).
For every couple of asteroids a dataframe is built: every row is associated to a specific timestep plus positions and velocities of the couple being investigated.
For every row, the distance and relative velocity is calculated and the threshold rules are checked. 
A couple of asteroids is interesting if the threshold rule is satisfied in at least one timestep. 
Once a couple is identified, a graph is built to show both distance and relative velocity.



Kind Regards,
Alessandro Odasso