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181736 (1995 US21)
Classification: Main-belt Asteroid          SPK-ID: 2181736
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]

[ show orbit diagram ]
Orbital Elements at Epoch 2459396.5 (2021-Jul-01.0) TDB
Reference: JPL 17 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .06233851725230072 4.0135e-08  
a 3.082064582129246 2.7993e-08 au
q 2.889933246003477 1.3108e-07 au
i 2.345956525796283 5.1461e-06 deg
node 8.986634350165168 0.00010896 deg
peri 294.0275452244484 0.00011831 deg
M 343.975487931811 4.8338e-05 deg
tp 2459484.471772564890
(2021-Sep-26.97177257)
0.00026569 TDB
period 1976.337125810495
5.41
2.6925e-05
7.372e-08
d
yr
n .1821551572849011 2.4816e-09 deg/d
Q 3.274195918255016 2.9738e-08 au
  Orbit Determination Parameters
   # obs. used (total)      344  
   data-arc span      9913 days (27.14 yr)  
   first obs. used      1993-04-21  
   last obs. used      2020-06-11  
   planetary ephem.      DE441  
   SB-pert. ephem.      SB441-N16  
   condition code      0  
   norm. resid. RMS      .53564  
   source      ORB  
   producer      Otto Matic  
   solution date      2021-Jul-09 11:22:38  

Additional Information
 Earth MOID = 1.87518 au 
 Jupiter MOID = 1.87548 au 
 T_jup = 3.223 
[ hide covariance matrix ]
Orbital Elements at Epoch 2457642.5 (2016-Sep-11.0) TDB
Reference: JPL 17 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .0606331581824187 4.0158e-08  
q 2.895632128580358 1.3102e-07 au
tp 2457508.335347818333
(2016-Apr-29.83534782)
0.00026553 TDB
node 9.026706061583704 0.00010895 deg
peri 293.9834152882174 0.00011876 deg
i 2.346063815885842 5.1459e-06 deg
  Orbit Determination Parameters
   # obs. used (total)      344  
   data-arc span      9913 days (27.14 yr)  
   first obs. used      1993-04-21  
   last obs. used      2020-06-11  
   planetary ephem.      DE441  
   SB-pert. ephem.      SB441-N16  
   condition code      0  
   norm. resid. RMS      .53564  
   source      ORB  
   producer      Otto Matic  
   solution date      2021-Jul-09 11:22:38  

Additional Information
 Jupiter MOID = 1.87548 au 
 T_jup = 3.223 
Orbit Covariance (6×6)
  e q tp node peri i
e 1.612699532442527E-15 -5.152899965793016E-15 -1.073715802944308E-12 1.094991384990865E-14 -1.652654778517507E-13 6.441754033028453E-16
q -5.152899965793016E-15 1.716616807635335E-14 4.664158063001305E-12 -3.359374402522894E-14 7.518916254813556E-13 -1.412131151447794E-15
tp -1.073715802944308E-12 4.664158063001305E-12 7.05084461822235E-8 -4.786757896418865E-11 1.25763387193781E-8 2.768444611362199E-12
node 1.094991384990865E-14 -3.359374402522894E-14 -4.786757896418865E-11 1.186974534138239E-8 -1.186750500830492E-8 7.563167185718144E-11
peri -1.652654778517507E-13 7.518916254813556E-13 1.25763387193781E-8 -1.186750500830492E-8 1.410371052964775E-8 -7.50432054759444E-11
i 6.441754033028453E-16 -1.412131151447794E-15 2.768444611362199E-12 7.563167185718144E-11 -7.50432054759444E-11 2.648030151469432E-11

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

Physical Parameter Table
Parameter Symbol Value Units Sigma Reference Notes
absolute magnitude H 15.79   n/a MPCxxxxx  

181736 (1995 US21)          Discovered 1995-Oct-19 by Spacewatch at Kitt Peak
Reference: 20080420/Numbers.arcLast Updated: 2008-04-23

[ hide close-approach data ]
Close-Approach Data   ...sorted by Date/Time (TDB)
Date/Time (TDB) Time Uncertainty
(days_HH:MM)
Body Nominal Distance (au) Minimum Distance (au) Maximum Distance (au) V-relative (km/s) V-infinity (km/s) JD (TDB) Time Uncertainty (minutes) Semi-major axis (km) Semi-minor axis (km) range-LOV angle (deg) N-sigma BP Orbit Ref. Reference Modified
1943-Jan-22 15:38 00:03 Jupiter 1.98179023448794 1.98178937000885 1.98179109896702 3.11899959741262 2.97881739528535 2430747.151381953 3.15888296761889 58.745933751265 28.2667555634141 -66.006270536118 2453615.91530077 T 17 CATAB v2.0g-lin.ifort 2021-Jul-09 11:22:40 2021-Jul-09 11:22
1952-Nov-18 17:07 00:03 Jupiter 1.86503297007095 1.86503247613583 1.86503346400617 3.11348820357603 2.96403267842738 2434335.212924793 2.75966157341944 82.2650552313242 15.138510821523 -88.0179924043591 2670570.81692262 T 17 CATAB v2.0g-lin.ifort 2021-Jul-09 11:22:40 2021-Jul-09 11:22
2012-Aug-13 08:27 < 00:01 Jupiter 1.86495830371163 1.8649578419545 1.86495876546865 3.00123221098792 2.84588111897782 2456152.851981539 0.276575139011773 40.8217438516162 13.7075079736735 -83.2258894249488 2841334.99603503 T 17 CATAB v2.0g-lin.ifort 2021-Jul-09 11:22:40 2021-Jul-09 11:22
2072-May-08 15:07 00:02 Jupiter 1.87712720432571 1.87712669880844 1.87712770984288 2.9449663008157 2.78753649143996 2477971.130170630 2.45794211553735 47.6782135521688 17.6365670330551 87.1170782305988 2953156.56519811 T 17 CATAB v2.0g-lin.ifort 2021-Jul-09 11:22:40 2021-Jul-09 11:22
2082-Mar-08 20:09 00:03 Jupiter 1.96494072996267 1.96493997912328 1.96494148080453 3.81288892530353 3.69810580245319 2481562.339342971 2.83398397228411 143.493863206903 17.7670485203226 -79.851051653118 3221198.40917912 T 17 CATAB v2.0g-lin.ifort 2021-Jul-09 11:22:40 2021-Jul-09 11:22
2132-Feb-03 07:04 00:05 Jupiter 1.90084720873766 1.90084638800202 1.90084802947319 2.9461470795081 2.7908022786702 2499789.794520631 5.02632412233543 51.0899720065582 30.8270759285884 71.2539960590659 2614437.88797744 T 17 CATAB v2.0g-lin.ifort 2021-Jul-09 11:22:40 2021-Jul-09 11:22
2141-Nov-30 14:09 00:05 Jupiter 1.92810101235346 1.92810000717041 1.92810201754528 3.58256772747301 3.45777146396885 2503378.089350876 5.41115192443433 240.09969471844 16.950268926535 -82.0631638337262 2992960.97390453 T 17 CATAB v2.0g-lin.ifort 2021-Jul-09 11:22:40 2021-Jul-09 11:22
2191-Oct-30 00:07 00:08 Jupiter 1.93483240851809 1.93483096967158 1.93483384736417 2.9989878261171 2.84927651966048 2521608.505057058 7.54742000372304 61.2333150668073 45.1785326107382 -23.769989572757 1546328.28415016 T 17 CATAB v2.0g-lin.ifort 2021-Jul-09 11:22:40 2021-Jul-09 11:22

Alternate Designations
 1995 US21 = 2006 US278 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]
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