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 ]  
21971 (1999 XG)
Classification: Main-belt Asteroid          SPK-ID: 2021971
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]

[ 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 .2162741161224878 4.7528e-08  
a 2.651278065188642 1.6784e-08 au
q 2.077875245045029 1.3333e-07 au
i 12.18329412875235 4.793e-06 deg
node 49.95288741019303 2.0461e-05 deg
peri 289.5154570240323 2.2854e-05 deg
M 337.9103193975719 1.2537e-05 deg
tp 2459297.253855643064
(2021-Mar-23.75385564)
5.5428e-05 TDB
period 1576.817187102032
4.32
1.4973e-05
4.099e-08
d
yr
n .228308013728357 2.1679e-09 deg/d
Q 3.224680885332256 2.0414e-08 au
  Orbit Determination Parameters
   # obs. used (total)      1154  
   data-arc span      13825 days (37.85 yr)  
   first obs. used      1982-10-16  
   last obs. used      2020-08-22  
   planetary ephem.      DE441  
   SB-pert. ephem.      SB441-N16  
   condition code      0  
   norm. resid. RMS      .55634  
   source      ORB  
   producer      Otto Matic  
   solution date      2021-Apr-13 03:56:34  

Additional Information
 Earth MOID = 1.10598 au 
 Jupiter MOID = 2.31726 au 
 T_jup = 3.325 
[ show covariance matrix ]

Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]

Physical Parameter Table
Parameter Symbol Value Units Sigma Reference Notes
absolute magnitude H 14.2   n/a MPO337444  
diameter diameter 8.167 km 0.227 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  
geometric albedo albedo 0.050   0.009 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  

21971 (1999 XG)          Discovered 1999-Dec-01 by LINEAR at Socorro
Reference: 20010208/Numbers.arcLast Updated: 2004-04-19

Alternate Designations
 1999 XG = 1982 UZ1 = 1998 HR71 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]
ABOUT SSD CREDITS/AWARDS PRIVACY/COPYRIGHT GLOSSARY LINKS
FirstGov 2021-Apr-16 12:36 UT
(server date/time)  
NASA Home Page
Site Manager:   Ryan S. Park
Webmaster  Alan B. Chamberlin