+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   6400 Georgealexander (1991 GQ1) Classification: Main-belt Asteroid          SPK-ID: 2006400 [ 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 .1542352387991775 1.5829e-08   a 3.017289566417666 1.6185e-08 au q 2.551917189614971 5.1958e-08 au i 12.71457640401281 6.6697e-07 deg node 87.52949933384519 4.3057e-06 deg peri 232.9177505671256 9.3042e-06 deg M 164.0768611433159 1.1107e-05 deg tp 2458327.993337732700 (2018-Jul-28.49333773) 5.7e-05 TDB period 1914.36133180211 5.24 1.5403e-05 4.217e-08 d yr n .1880522731103794 1.5131e-09 deg/d Q 3.482661943220362 1.8681e-08 au   Orbit Determination Parameters    # obs. used (total)      2885      data-arc span      11341 days (31.05 yr)      first obs. used      1990-02-24      last obs. used      2021-03-14      planetary ephem.      DE441      SB-pert. ephem.      SB441-N16      condition code      0      norm. resid. RMS      .38847      source      ORB      producer      Otto Matic      solution date      2021-Apr-12 18:40:11   Additional Information  Earth MOID = 1.55946 au   Jupiter MOID = 1.85154 au   T_jup = 3.192  [ 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 12.07   n/a E2021B10   diameter diameter 12.100 km 0.098 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   rotation period rot_per 41.3476 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: [McNeill, A.; Mommert, M.; Trilling, D.E.; Llama, J.; Skiff, B. (2019) Ap. J. Suppl. Series 245, id.29.] [Pal, A.; Szakats, R.; Kiss, C.; Bodi, A.; et al. (2019) Ap. J. Supl. Ser. 247, id.26.] geometric albedo albedo 0.399   0.072 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   6400 Georgealexander           Discovered 1991 Apr. 10 by E. F. Helin at Palomar Observatory. Named in honor of George Alexander, soon to retire from the Jet propulsion Laboratory as public-affairs manager. He has spent almost 40 years communicating science and space exploration to the public. After seven years as a reporter for Aviation Week magazine, he went to Newsweek in 1967, writing all the cover stories about the Apollo moon program. Alexander left Newsweek to become science writer for The Los Angeles Times, and he won several major awards for excellence in science writing. He became very well acquainted with JPL through his coverage of the Viking, Voyager and other missions, and he joined the staff in 1988. He was president of both the National Association of Science Writers and the Council for the Advancement of Science Writing in the 1970s and 1980s. NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character) Reference: 19990728/MPCPages.arc Last Updated: 2010-06-11 [ show close-approach data ] Alternate Designations  1991 GQ1 = 1992 QL1  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Apr-22 04:01 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin