Skip Page Navigation
NASA JPL Caltech
NASA Logo - Jet Propulsion Laboratory + View the NASA Portal
+ Center for Near-Earth Object Studies
JPL Home Earth Solar System Stars & Galaxies Technology
JPL Solar System Dynamics
BODIES ORBITS EPHEMERIDES TOOLS PHYSICAL DATA DISCOVERY FAQ SITE MAP
JPL Small-Body Database Browser
Search: [ help ]  
21781 (1999 RE239)
Classification: Main-belt Asteroid          SPK-ID: 2021781
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]

[ show orbit diagram ]
Orbital Elements at Epoch 2459200.5 (2020-Dec-17.0) TDB
Reference: JPL 27 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .03257696524065343 4.4118e-08  
a 2.40914285975563 1.0433e-08 au
q 2.330660296553603 1.0997e-07 au
i 7.740441054908188 4.4849e-06 deg
node 129.6836946268607 2.9712e-05 deg
peri 101.9542491310906 8.5762e-05 deg
M 14.98951233779902 8.1911e-05 deg
tp 2459143.630781391981
(2020-Oct-21.13078139)
0.00031072 TDB
period 1365.816194517565
3.74
8.8719e-06
2.429e-08
d
yr
n .2635786582741169 1.7121e-09 deg/d
Q 2.487625422957658 1.0772e-08 au
  Orbit Determination Parameters
   # obs. used (total)      1097  
   data-arc span      10041 days (27.49 yr)  
   first obs. used      1992-12-01  
   last obs. used      2020-05-29  
   planetary ephem.      DE441  
   SB-pert. ephem.      SB441-N16  
   condition code      0  
   norm. resid. RMS      .53896  
   source      ORB  
   producer      Otto Matic  
   solution date      2021-Apr-13 03:53:18  

Additional Information
 Earth MOID = 1.33099 au 
 Jupiter MOID = 2.50677 au 
 T_jup = 3.508 
[ 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 15.31   n/a E2021B10  
diameter diameter 2.153 km 0.309 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  
rotation period rot_per 26.7448 h n/a LCDB (Rev. 2020-October); Warner et al., 2009 Result based on less than full coverage, so that the period may be wrong by 30 percent or so.
Published Reference List:
[Pal, A.; Szakats, R.; Kiss, C.; Bodi, A.; et al. (2019) Ap. J. Supl. Ser. 247, id.26.]
geometric albedo albedo 0.347   0.033 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  

21781 (1999 RE239)          Discovered 1999-Sep-08 by CSS at Catalina
Reference: 20010208/Numbers.arcLast Updated: 2004-04-19

[ show close-approach data ]
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]
ABOUT SSD CREDITS/AWARDS PRIVACY/COPYRIGHT GLOSSARY LINKS
FirstGov 2021-Apr-20 11:11 UT
(server date/time)  
NASA Home Page
Site Manager:   Ryan S. Park
Webmaster  Alan B. Chamberlin