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 ]  
18758 (1999 HD2)
Classification: Main-belt Asteroid          SPK-ID: 2018758
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 36 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .1844022001600467 4.1258e-08  
a 2.188786055432896 6.6288e-09 au
q 1.78516909113144 8.9921e-08 au
i 5.740390418069251 4.8635e-06 deg
node 128.882423637394 3.77e-05 deg
peri 247.6851208206276 3.9542e-05 deg
M 86.9780358541551 1.312e-05 deg
tp 2458914.734041966001
(2020-Mar-06.23404197)
4.2606e-05 TDB
period 1182.778432301484
3.24
5.3731e-06
1.471e-08
d
yr
n .3043680795730286 1.3827e-09 deg/d
Q 2.592403019734352 7.8512e-09 au
  Orbit Determination Parameters
   # obs. used (total)      1621  
   data-arc span      14306 days (39.17 yr)  
   first obs. used      1982-01-19  
   last obs. used      2021-03-21  
   planetary ephem.      DE441  
   SB-pert. ephem.      SB441-N16  
   condition code      0  
   norm. resid. RMS      .51879  
   source      ORB  
   producer      Otto Matic  
   solution date      2021-May-04 02:47:13  

Additional Information
 Earth MOID = .794158 au 
 Jupiter MOID = 2.88319 au 
 T_jup = 3.646 
[ 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 14.87   n/a MPCxxxxx  
rotation period rot_per 5.132 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:
[Waszczak, A.; Chang, C.-K.; Ofeck, E.O.; Laher, F.; et al. (2015) Astron. J. 150, A75.]

18758 (1999 HD2)          Discovered 1999-Apr-19 by Korlevic, K., Juric, M. at Visnjan
Reference: 20001111/Numbers.arcLast Updated: 2004-04-19

Alternate Designations
 1999 HD2 = 1982 BY9 = 1987 SQ2 = 1992 EU4 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]
ABOUT SSD CREDITS/AWARDS PRIVACY/COPYRIGHT GLOSSARY LINKS
FirstGov 2021-Jun-17 21:51 UT
(server date/time)  
NASA Home Page
Site Manager:   Ryan S. Park
Webmaster  Alan B. Chamberlin