+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   8149 Ruff (1985 JN1) Classification: Main-belt Asteroid          SPK-ID: 2008149 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] [ show orbit diagram ] Orbital Elements at Epoch 2459000.5 (2020-May-31.0) TDB Reference: JPL 36 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .143104022418438 3.2101e-08   a 2.32232428393226 7.461e-09 au q 1.989990337541535 7.6054e-08 au i 6.587746529668156 3.4407e-06 deg node 81.33625987412361 3.6159e-05 deg peri 170.290282757599 3.9836e-05 deg M 311.1301714256963 1.8783e-05 deg tp 2459175.977337779697 (2020-Nov-22.47733778) 6.7761e-05 TDB period 1292.655273071845 3.54 6.2294e-06 1.706e-08 d yr n .2784965237827886 1.3421e-09 deg/d Q 2.654658230322985 8.5287e-09 au   Orbit Determination Parameters    # obs. used (total)      2358      data-arc span      25121 days (68.78 yr)      first obs. used      1951-11-08      last obs. used      2020-08-18      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .45405      source      ORB      producer      Otto Matic      solution date      2020-Nov-13 03:22:58   Additional Information  Earth MOID = .975868 au   Jupiter MOID = 2.38028 au   T_jup = 3.554  [ show covariance matrix ] [ 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 13.4   n/a MPO358710   diameter diameter 4.091 km 0.132 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   rotation period rot_per 5.1704 h n/a LCDB (Rev. 2020-October); Warner et al., 2009 Published Reference List: [Pravec, P.; Wolf, M.; Sarounova, L. (2020) http://www.asu.cas.cz/~ppravec/neo.htm] geometric albedo albedo 0.554   0.116 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   8149 Ruff           Discovered 1985 May 11 by C. Shoemaker and E. Shoemaker at Palomar. Jan Ruff (b. 1949) is the very capable, warm-spirited and enthusiastic chief of the Office of Public Affairs for Goddard Space Center, NASA. Steve Ruff (b. 1949) is an imaginative, creative and knowledgeable middle-school teacher with a wonderful dry sense of humor. NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character) Reference: 20000320/MPCPages.arc Last Updated: 2013-03-29 [ show close-approach data ] Alternate Designations  1985 JN1 = 1992 HC  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Jan-24 23:04 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin