+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   2180 Marjaleena (1940 RJ) Classification: Main-belt Asteroid          SPK-ID: 2002180 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] [ show orbit diagram ] Orbital Elements at Epoch 2459200.5 (2020-Dec-17.0) TDB Reference: JPL 46 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .07929853642941061 2.3336e-08   a 3.013461991263279 1.4458e-08 au q 2.774498865770444 7.1459e-08 au i 9.248824716431027 1.0632e-07 deg node 233.2746867702275 3.4448e-06 deg peri 88.64812763598192 1.4531e-05 deg M 154.543900613921 1.7861e-05 deg tp 2458380.249747646883 (2018-Sep-18.74974765) 9.3239e-05 TDB period 1910.719799837399 5.23 1.3751e-05 3.765e-08 d yr n .1884106712196292 1.356e-09 deg/d Q 3.252425116756115 1.5605e-08 au   Orbit Determination Parameters    # obs. used (total)      3163      data-arc span      25312 days (69.30 yr)      first obs. used      1951-12-01      last obs. used      2021-03-20      planetary ephem.      DE441      SB-pert. ephem.      SB441-N16      condition code      0      norm. resid. RMS      .38764      source      ORB      producer      Otto Matic      solution date      2021-May-03 20:02:08   Additional Information  Earth MOID = 1.78038 au   Jupiter MOID = 1.99284 au   T_jup = 3.224  [ 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 11.14   n/a E2021B10   diameter diameter 21.357 km 0.167 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)   rotation period rot_per 7.717 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: [Behrend, R. (2014) Observatoire de Geneve web site, http://obswww.unige.ch/~behrend/page_cou.html] [Waszczak, A.; Chang, C.-K.; Ofeck, E.O.; Laher, F.; et al. (2015) Astron. J. 150, A75.] [Polakis, T. (2020) Minor Planet Bull. 47, 94-101.] geometric albedo albedo 0.154   0.017 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2014ApJ...791..121M)   2180 Marjaleena (1940 RJ)          Discovered 1940-Sep-08 by Alikoski, H. at Turku Reference: DISCOVERY.DB Last Updated: 2003-08-29 [ show close-approach data ] Alternate Designations  1940 RJ = 1950 NQ1 = 1970 JL = 1970 JR = 1971 OL1 = 1976 NM = 1977 TT3  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-May-14 00:22 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin