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 ]  
30744 (1981 EN18)
Classification: Main-belt Asteroid          SPK-ID: 2030744
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]

[ hide orbit diagram ]

For accurate long-term ephemerides, please instead use our Horizons system.This orbit viewer was implemented using two-body methods, and hence should not be used for determining accurate long-term trajectories (over several years or decades) or planetary encounter circumstances.


Orbital Elements at Epoch 2459396.5 (2021-Jul-01.0) TDB
Reference: JPL 17 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .1070942853706193 5.2235e-08  
a 3.139591323461939 2.5147e-08 au
q 2.803359034319986 1.5627e-07 au
i 5.463378197062945 6.4684e-06 deg
node 199.0373795593601 4.4759e-05 deg
peri 307.2238143263114 5.1859e-05 deg
M 116.7871243414336 2.5763e-05 deg
tp 2458737.325237622380
(2019-Sep-10.82523762)
0.00014426 TDB
period 2031.927027864605
5.56
2.4413e-05
6.684e-08
d
yr
n .1771717168299748 2.1286e-09 deg/d
Q 3.475823612603892 2.784e-08 au
  Orbit Determination Parameters
   # obs. used (total)      501  
   data-arc span      14398 days (39.42 yr)  
   first obs. used      1981-02-09  
   last obs. used      2020-07-12  
   planetary ephem.      DE441  
   SB-pert. ephem.      SB441-N16  
   condition code      0  
   norm. resid. RMS      .56683  
   source      ORB  
   producer      Otto Matic  
   solution date      2021-Apr-13 06:39:38  

Additional Information
 Earth MOID = 1.81993 au 
 Jupiter MOID = 1.55493 au 
 T_jup = 3.195 
[ hide covariance matrix ]
Orbital Elements at Epoch 2457155.5 (2015-May-13.0) TDB
Reference: JPL 17 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .1089028637176448 5.2146e-08  
q 2.796886257748327 1.5647e-07 au
tp 2456703.364211111454
(2014-Feb-14.86421111)
0.00014132 TDB
node 199.0779991007769 4.4769e-05 deg
peri 306.8649111384078 5.164e-05 deg
i 5.463485961622464 6.469e-06 deg
  Orbit Determination Parameters
   # obs. used (total)      501  
   data-arc span      14398 days (39.42 yr)  
   first obs. used      1981-02-09  
   last obs. used      2020-07-12  
   planetary ephem.      DE441  
   SB-pert. ephem.      SB441-N16  
   condition code      0  
   norm. resid. RMS      .56683  
   source      ORB  
   producer      Otto Matic  
   solution date      2021-Apr-13 06:39:38  

Additional Information
 Jupiter MOID = 1.55493 au 
 T_jup = 3.195 
Orbit Covariance (6×6)
  e q tp node peri i
e 2.719208490081594E-15 -8.086949135737919E-15 2.56247864303278E-12 9.733645247315331E-15 4.613995343253698E-13 -5.224341780368739E-20
q -8.086949135737919E-15 2.448338796043397E-14 -8.250311384553421E-12 -2.877640616093707E-14 -1.467405824451861E-12 6.530700986924108E-16
tp 2.56247864303278E-12 -8.250311384553421E-12 1.997039601043728E-8 1.861389129688223E-11 3.651114213668406E-9 -9.076546934360952E-13
node 9.733645247315331E-15 -2.877640616093707E-14 1.861389129688223E-11 2.004270234330092E-9 -1.991254493447542E-9 -2.630719559803158E-11
peri 4.613995343253698E-13 -1.467405824451861E-12 3.651114213668406E-9 -1.991254493447542E-9 2.666706551364469E-9 2.609557557905573E-11
i -5.224341780368739E-20 6.530700986924108E-16 -9.076546934360952E-13 -2.630719559803158E-11 2.609557557905573E-11 4.184816217678847E-11

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 15.13   n/a E2021B10  

30744 (1981 EN18)          Discovered 1981-Mar-02 by Bus, S. J. at Siding Spring
Reference: 20011130/Numbers.arcLast Updated: 2004-04-19

[ show close-approach data ]
Alternate Designations
 1981 EN18 = 1998 HR73 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]
ABOUT SSD CREDITS/AWARDS PRIVACY/COPYRIGHT GLOSSARY LINKS
FirstGov 2021-Sep-17 15:54 UT
(server date/time)  
NASA Home Page
Site Manager:   Ryan S. Park
Webmaster  Alan B. Chamberlin