+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   18851 Winmesser (1999 RP84) Classification: Main-belt Asteroid          SPK-ID: 2018851 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] [ show orbit diagram ] Orbital Elements at Epoch 2459396.5 (2021-Jul-01.0) TDB Reference: JPL 32 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .1698573305157335 3.142e-08   a 2.377877040165945 7.5676e-09 au q 1.973977193828704 7.3544e-08 au i 3.581800577244093 3.1871e-06 deg node 272.1164503237761 5.4352e-05 deg peri 266.7273618943385 5.517e-05 deg M 158.0050917895591 9.1036e-06 deg tp 2458808.670876635727 (2019-Nov-21.17087664) 3.3614e-05 TDB period 1339.314334837924 3.67 6.3936e-06 1.75e-08 d yr n .2687942558634417 1.2832e-09 deg/d Q 2.781776886503187 8.853e-09 au   Orbit Determination Parameters    # obs. used (total)      2106      data-arc span      10932 days (29.93 yr)      first obs. used      1991-07-07      last obs. used      2021-06-11      planetary ephem.      DE441      SB-pert. ephem.      SB441-N16      condition code      0      norm. resid. RMS      .46792      source      ORB      producer      Otto Matic      solution date      2021-Jul-09 14:00:19   Additional Information  Earth MOID = .982285 au   Jupiter MOID = 2.19861 au   T_jup = 3.518  [ 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 14.39   n/a E2021B10   diameter diameter 7.609 km 0.072 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   rotation period rot_per 27.327 h n/a LCDB (Rev. 2020-October); Warner et al., 2009 Published Reference List: [Pravec, P.; Wolf, M.; Sarounova, L. (2016) http://www.asu.cas.cz/~ppravec/neo.htm] [Oey, J.; Groom, R. (2019) Minor Planet Bull. 46, 119-125.] geometric albedo albedo 0.058   0.010 urn:nasa:pds:neowise_diameters_albedos::2.0[mainbelt] (http://adsabs.harvard.edu/abs/2011ApJ...741...68M)   18851 Winmesser           Discovered 1999 Sept. 7 by the Lincoln Laboratory Near-Earth Asteroid Research Team at Socorro. Winston Harmon Messer (b. 1986) was awarded third place in the 2003 Intel International Science and Engineering Fair for his medicine and health project. He attends the Presbyterian Christian School, Hattiesburg, Mississippi, U.S.A. NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character) Reference: 20040830/MPCPages.arc Last Updated: 2004-09-06 Alternate Designations  1999 RP84 = 1991 NX3 = 1998 KL64  [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances ] 2021-Aug-03 15:09 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin