+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   363027 (1998 ST27) Classification: Aten [NEO, PHA]          SPK-ID: 2363027 [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] [ show orbit diagram ] Orbital Elements at Epoch 2459396.5 (2021-Jul-01.0) TDB Reference: JPL 86 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .5299983377743313 1.4144e-07   a .8193794586104065 4.4018e-09 au q .3851097075404596 1.1409e-07 au i 21.0603915439424 1.1122e-05 deg node 197.5396893294054 5.6382e-06 deg peri 322.4732139540999 7.4015e-06 deg M 117.3077160452586 2.1824e-05 deg tp 2459308.222482078047 (2021-Apr-03.72248208) 1.5819e-05 TDB period 270.9106231310644 0.74 2.183e-06 5.977e-09 d yr n 1.328851544613793 1.0708e-08 deg/d Q 1.253649209680353 6.7347e-09 au Additional Model Parameters  Parameter Value Uncertainty (1-sigma)  A2 [EST] 2.029333891966252E-14 3.895E-15 ALN [SET] 1. n/a NK [SET] 0. n/a NM [SET] 2. n/a R0 [SET] 1. n/a   Orbit Determination Parameters    # obs. used (total)      407      # delay obs. used      6      # Doppler obs. used      1      data-arc span      7309 days (20.01 yr)      first obs. used      1998-09-24      last obs. used      2018-09-28      planetary ephem.      DE441      SB-pert. ephem.      SB441-N16      condition code      0      norm. resid. RMS      .38028      source      ORB      producer      Otto Matic      solution date      2021-Apr-14 09:41:47   Additional Information  Earth MOID = .00978374 au   Jupiter MOID = 3.76207 au   T_jup = 6.978   Nongravitational accels. using nonstandard g(r) = (1 au/ r)^2  [ 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 19.5   n/a MPO260882   diameter diameter 0.578 km 0.228 urn:nasa:pds:neowise_diameters_albedos::2.0[neos] (http://adsabs.harvard.edu/abs/2016AJ....152...63N)   rotation period rot_per 3. 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: [Benner, L.A.M.; Nolan, M.C.; Ostro, S.J.; Giorgini, J.D.; Margot, J.-L. (2001) IAUC 7730.] geometric albedo albedo 0.059   0.066 urn:nasa:pds:neowise_diameters_albedos::2.0[neos] (http://adsabs.harvard.edu/abs/2016AJ....152...63N)   363027 (1998 ST27)          Discovered 1998-Sep-24 by LINEAR at Socorro Reference: Last Updated: 2013-06-26 [ show close-approach data ] [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Jul-24 11:20 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin