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 ]  
21785 Mechain (1999 SS2)
Classification: Main-belt Asteroid          SPK-ID: 2021785
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]

[ 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.


[ revert to old Java-based viewer ]

Orbital Elements at Epoch 2459000.5 (2020-May-31.0) TDB
Reference: JPL 24 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .1723682696965048 5.5213e-08  
a 2.776102900793588 1.788e-08 au
q 2.297590847284349 1.5389e-07 au
i 18.66522583600731 6.3124e-06 deg
node 22.89574195570559 1.4017e-05 deg
peri 358.8702284171279 1.9488e-05 deg
M 154.3990337768566 1.6394e-05 deg
tp 2458275.907483826637
(2018-Jun-06.40748383)
7.2949e-05 TDB
period 1689.474988550808
4.63
1.6322e-05
4.469e-08
d
yr
n .2130839476403255 2.0586e-09 deg/d
Q 3.254614954302826 2.0962e-08 au
  Orbit Determination Parameters
   # obs. used (total)      758  
   data-arc span      15892 days (43.51 yr)  
   first obs. used      1976-10-22  
   last obs. used      2020-04-26  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .52015  
   source      ORB  
   producer      Otto Matic  
   solution date      2020-May-20 05:25:53  

Additional Information
 Earth MOID = 1.30089 au 
 Jupiter MOID = 2.20586 au 
 T_jup = 3.238 
[ 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 14.7   n/a MPO467964  
diameter diameter 4.488 km 0.362 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  
geometric albedo albedo 0.152   0.028 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)  

21785 Méchain           Discovered 1999 Sept. 21 by M. Tichy at Klet.
Pierre François André Méchain (1744-1804) discovered many comets and deep-sky objects. A colleague and friend of Messier, he contributed much to Messier's catalogue of nebulae. Much of Méchain's career involved geodetic measurements along the Paris meridian, with the idea of defining the meter.
NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character)
Reference: 20020624/MPCPages.arcLast Updated: 2003-10-02

Alternate Designations
 1999 SS2 = 1976 UX5 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ]
ABOUT SSD CREDITS/AWARDS PRIVACY/COPYRIGHT GLOSSARY LINKS
FirstGov 2020-Aug-04 21:21 UT
(server date/time)  
NASA Home Page
Site Manager:   Ryan S. Park
Webmaster  Alan B. Chamberlin