+ View the NASA Portal + Center for Near-Earth Object Studies JPL Small-Body Database Browser Search: [ help ]   161989 Cacus (1978 CA) Classification: Apollo [NEO, PHA]          SPK-ID: 2161989 [ 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 177 (heliocentric ecliptic J2000)  Element Value Uncertainty (1-sigma)   Units  e .2140241875160391 7.0169e-08   a 1.123105696512069 2.2971e-09 au q .8827339123214383 7.7898e-08 au i 26.06074976550623 1.0264e-05 deg node 161.2317878603156 6.274e-06 deg peri 102.1842831670446 1.5652e-05 deg M 93.44819765079295 1.913e-05 deg tp 2458887.650977736467 (2020-Feb-08.15097774) 2.2847e-05 TDB period 434.7397706554606 1.19 1.3338e-06 3.652e-09 d yr n .828081588802481 2.5405e-09 deg/d Q 1.3634774807027 2.7887e-09 au   Orbit Determination Parameters    # obs. used (total)      1091      data-arc span      15685 days (42.94 yr)      first obs. used      1978-02-08      last obs. used      2021-01-18      planetary ephem.      DE431      SB-pert. ephem.      SB431-N16      condition code      0      norm. resid. RMS      .38086      source      ORB      producer      Otto Matic      solution date      2021-Jan-19 05:28:16   Additional Information  Earth MOID = .0156073 au   Jupiter MOID = 3.81134 au   T_jup = 5.448  [ 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 17.2   n/a MPO366964   diameter diameter 1.9 km n/a Hazards due to Comets and Asteroids (1994), Ed. T. Gehrels, pp.540-543   rotation period rot_per 3.7538 h n/a LCDB (Rev. 2020-October); Warner et al., 2009 Published Reference List: [Degewij, J. (1978) Messenger 13, 5; IAUC 3193.] [Schuster, H.E.; Surdej, A.; Surdej, J. (1979) Astron. Astrophys. Suppl. Ser. 37, 483-486.] [Pravec, P.; Wolf, M.; Sarounova, L. (2003) http://www.asu.cas.cz/~ppravec/neo.htm] [Koehn, B.W.; Bowell, E.L.G.; Skiff, B.A.; Sanborn, J.J.; et al. (2014) Minor Planet Bull. 41, 286-300.] [Durech, J.; Vokrouhlicky, D.; Pravec, P.; Hanus, J.; et al. (2018) Astron. Astrophys. 609, A86.] [Skiff, B.A.; McLelland, K.P.; Sanborn, J.; Pravec, P.; Koehn, B.W. (2019). Minor Planet Bull. 46, 458-503.] geometric albedo albedo 0.09   n/a Hazards due to Comets and Asteroids (1994), Ed. T. Gehrels, pp.540-543   B-V BV 0.910   0.017 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2 #obs=3; phase (min.=8.42, mean=14.40, max.=26.34) deg. U-B UB 0.484   0.020 EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2 #obs=3; phase (min.=8.42, mean=14.40, max.=26.34) deg. Tholen spectral type spec_T S   n/a EAR-A-5-DDR-TAXONOMY-V4.0 used 2 color indices 161989 Cacus           Discovered 1978 Feb. 8 by H.-E. Schuster at the European Southern Observatory. The fire-breathing monster Cacus, son of Vulcan, stole cattle Hercules had acquired as his tenth labor. Although Cacus tried to make it appear that the cattle had gone in the opposite direction, Hercules found them and strangled Cacus, erecting an altar at the spot that later became the Forum Boarium, the Rome cattle market. NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character) Reference: 20071124/MPCPages.arc Last Updated: 2007-11-26 [ show close-approach data ] [ Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ] 2021-Jan-23 12:33 UT (server date/time)   Site Manager:   Ryan S. Park Webmaster:   Alan B. Chamberlin