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

Significant website upgrade scheduled for September 27. More details available here.

JPL Small-Body Database Browser
Search: [ help ]  
18718 (1998 HJ128)
Classification: Main-belt Asteroid          SPK-ID: 2018718
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]

[ show orbit diagram ]
Orbital Elements at Epoch 2459396.5 (2021-Jul-01.0) TDB
Reference: JPL 32 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .09286762358908363 1.439e-08  
a 2.604033836248769 1.074e-08 au
q 2.362203402130781 4.109e-08 au
i 14.61543401057627 8.5318e-07 deg
node 159.7426197166637 4.0877e-06 deg
peri 247.3453628323009 1.3027e-05 deg
M 321.3201419425922 1.5749e-05 deg
tp 2459561.411420422783
(2021-Dec-12.91142042)
6.7564e-05 TDB
period 1534.858562926707
4.20
9.4952e-06
2.6e-08
d
yr
n .2345492990009079 1.451e-09 deg/d
Q 2.845864270366757 1.1737e-08 au
  Orbit Determination Parameters
   # obs. used (total)      2085  
   data-arc span      11872 days (32.50 yr)  
   first obs. used      1989-02-05  
   last obs. used      2021-08-08  
   planetary ephem.      DE441  
   SB-pert. ephem.      SB441-N16  
   condition code      0  
   norm. resid. RMS      .43472  
   source      ORB  
   producer      Otto Matic  
   solution date      2021-Aug-24 22:12:19  

Additional Information
 Earth MOID = 1.40777 au 
 Jupiter MOID = 2.49282 au 
 T_jup = 3.361 
[ hide covariance matrix ]
Orbital Elements at Epoch 2456821.5 (2014-Jun-13.0) TDB
Reference: JPL 32 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .09476912554349197 1.4262e-08  
q 2.357954702318187 4.0771e-08 au
tp 2456494.785557602666
(2013-Jul-21.28555760)
6.135e-05 TDB
node 159.8390014129926 4.0973e-06 deg
peri 248.0295279892918 1.2833e-05 deg
i 14.59627128165805 8.5217e-07 deg
  Orbit Determination Parameters
   # obs. used (total)      2085  
   data-arc span      11872 days (32.50 yr)  
   first obs. used      1989-02-05  
   last obs. used      2021-08-08  
   planetary ephem.      DE441  
   SB-pert. ephem.      SB441-N16  
   condition code      0  
   norm. resid. RMS      .43472  
   source      ORB  
   producer      Otto Matic  
   solution date      2021-Aug-24 22:12:19  

Additional Information
 Jupiter MOID = 2.49282 au 
 T_jup = 3.361 
Orbit Covariance (6×6)
  e q tp node peri i
e 2.033982095583516E-16 -5.663550708680492E-16 -3.449971796085477E-13 7.588949048988906E-15 -8.606120466536566E-14 8.383165428324761E-16
q -5.663550708680492E-16 1.66231048888881E-15 9.825726925749514E-13 -1.862556735316415E-14 2.488244815935381E-13 -2.011689496594582E-15
tp -3.449971796085477E-13 9.825726925749514E-13 3.763873057138171E-9 2.576297694911729E-11 7.489867011137914E-10 -1.449458741454629E-12
node 7.588949048988906E-15 -1.862556735316415E-14 2.576297694911729E-11 1.67881429879441E-11 -1.03326413062335E-11 2.68154362219715E-12
peri -8.606120466536566E-14 2.488244815935381E-13 7.489867011137914E-10 -1.03326413062335E-11 1.646896571344828E-10 -2.986087276035635E-12
i 8.383165428324761E-16 -2.011689496594582E-15 -1.449458741454629E-12 2.68154362219715E-12 -2.986087276035635E-12 7.262017659624116E-13

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

Physical Parameter Table
Parameter Symbol Value Units Sigma Reference Notes
absolute magnitude H 13.39   n/a MPO636346  
diameter diameter 5.550 km 0.139 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  
geometric albedo albedo 0.301   0.040 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  

18718 (1998 HJ128)          Discovered 1998-Apr-19 by LINEAR at Socorro
Reference: 20001111/Numbers.arcLast Updated: 2004-04-19

Alternate Designations
 1998 HJ128 = 1989 CB7 = 1999 NL58 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]
ABOUT SSD CREDITS/AWARDS PRIVACY/COPYRIGHT GLOSSARY LINKS
FirstGov 2021-Sep-22 02:38 UT
(server date/time)  
NASA Home Page
Site Manager:   Ryan S. Park
Webmaster  Alan B. Chamberlin