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1484 Postrema (1938 HC)
Classification: Main-belt Asteroid          SPK-ID: 2001484
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 43 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .2051727964739255 1.2014e-08  
a 2.738389965825064 1.01e-08 au
q 2.176546838700598 3.2186e-08 au
i 17.28494593201207 4.8692e-07 deg
node 72.6592874811477 1.1934e-06 deg
peri 127.0027671100858 4.4061e-06 deg
M 137.5178908167704 4.1715e-06 deg
tp 2458764.236558422213
(2019-Oct-07.73655842)
1.6853e-05 TDB
period 1655.16528515754
4.53
9.1572e-06
2.507e-08
d
yr
n .2175009367513014 1.2033e-09 deg/d
Q 3.300233092949529 1.2172e-08 au
  Orbit Determination Parameters
   # obs. used (total)      2576  
   data-arc span      32313 days (88.47 yr)  
   first obs. used      1933-02-18  
   last obs. used      2021-08-08  
   planetary ephem.      DE441  
   SB-pert. ephem.      SB441-N16  
   condition code      0  
   norm. resid. RMS      .38626  
   source      ORB  
   producer      Otto Matic  
   solution date      2021-Aug-25 07:45:24  

Additional Information
 Earth MOID = 1.2143 au 
 Jupiter MOID = 1.82082 au 
 T_jup = 3.256 
[ show covariance matrix ]

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 10.99   n/a E2021B10  
diameter diameter 40.871 km 0.279 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)  
rotation period rot_per 12.1923 h n/a LCDB (Rev. 2020-October); Warner et al., 2009 Published Reference List:
[Behrend, R. (2006) Observatoire de Geneve web site, http://obswww.unige.ch/~behrend/page_cou.html]
[Julian, W.M. (2006) Minor Planet Bull. 33, 103-104.]
[Durech, J.; Hanus, J.; Oszkiewsicz, D.; Vanco, R. (2016) Astron. Astrophys. 587, A48.]
geometric albedo albedo 0.015   0.009 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)  
SMASSII spectral type spec_B B   n/a EAR-A-5-DDR-TAXONOMY-V4.0 based on a high-resolution spectrum by Xu et al. (1995) or Bus and Binzel (2002)

1484 Postrema (1938 HC)          Discovered 1938-Apr-29 by Neujmin, G. at Simeis
Reference: DISCOVERY.DBLast Updated: 2003-08-29

[ 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
1940-Nov-03 17:15 00:01 Jupiter 1.82200120086813 1.82200101777941 1.82200138396142 3.90978469355222 3.78901632646309 2429937.218615470 1.12780312799795 154.278470763052 2.43831862026505 -88.2531720020171 22529594.7822345 T 43 CATAB v2.0g-lin.ifort 2021-Aug-25 07:46:29 2021-Aug-25 07:46
1999-May-26 12:38 < 00:01 Jupiter 1.90324348755817 1.90324334057284 1.90324363454349 2.85355885945756 2.69308651568282 2451325.026640973 0.295508085412558 28.5050577817867 10.0139406546106 -80.3056225014775 8299542.35892686 T 43 CATAB v2.0g-lin.ifort 2021-Aug-25 07:46:29 2021-Aug-25 07:46
2036-Mar-03 07:11 < 00:01 Jupiter 1.8854695165564 1.88546937144596 1.88546966166726 4.38772348411511 4.2841152576392 2464755.799307318 0.313674359343753 52.6189854217854 2.73279778021716 -83.4002348611447 23721951.1011261 T 43 CATAB v2.0g-lin.ifort 2021-Aug-25 07:46:29 2021-Aug-25 07:46
2094-Oct-08 21:03 00:01 Jupiter 1.81876357765399 1.81876330188362 1.81876385342653 3.67460046763501 3.54559753228986 2486159.376900281 1.22113437736608 108.599337974723 4.80298850931576 80.2820122940743 21448277.5463927 T 43 CATAB v2.0g-lin.ifort 2021-Aug-25 07:46:29 2021-Aug-25 07:46
2153-Apr-15 00:52 00:03 Jupiter 1.99364332555334 1.99364185880408 1.99364479245456 2.41371927442654 2.23076612796474 2507531.536359181 2.5870964395886 911.587053348044 8.36319947383538 -80.8065329214542 8216208.45939878 T 43 CATAB v2.0g-lin.ifort 2021-Aug-25 07:46:29 2021-Aug-25 07:46
2190-Feb-08 04:20 00:03 Jupiter 1.81041809563813 1.81041754904969 1.81041864225661 4.18462904419632 4.07128971029044 2520979.680657336 2.55165284402122 375.751603126453 2.32804730403597 -86.6731943212544 24517307.3741731 T 43 CATAB v2.0g-lin.ifort 2021-Aug-25 07:46:29 2021-Aug-25 07:46

Alternate Designations
 1938 HC = 1933 DH = A911 KC 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]
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