60 Echo

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60 Echo
Discovery
Discovered by James Ferguson
Discovery date September 14, 1860
Designations
Named after Echo
Alternative names  
Minor planet category Main belt
Adjective Echonian
Orbital characteristics
Epoch December 31, 2006 (JD 2454100.5)
Aphelion 423.339 Gm (2.830 AU)
Perihelion 292.951 Gm (1.958 AU)
Semi-major axis 358.145 Gm (2.394 AU)
Eccentricity 0.182
Orbital period 1353.002 d (3.70 a)
Average orbital speed 19.09 km/s
Mean anomaly 91.065°
Inclination 3.602°
Longitude of ascending node 191.803°
Argument of perihelion 270.477°
Physical characteristics
Dimensions 60.2 km[1]
Mass (3.15 ± 0.32) × 1017[2] kg
Mean density 2.78 ± 0.33[2] g/cm3
Equatorial surface gravity 0.0168 m/s²
Escape velocity 0.0318 km/s
Rotation period 25.2 hr[1]
Albedo 0.254[1][3]
Temperature ~180 K
Spectral type S[1]
Absolute magnitude (H) 8.21[1]

60 Echo is a quite large main-belt S-type asteroid. It was discovered by James Ferguson of the United States Naval Observatory in Washington D.C., on September 14, 1860. It was his third and final asteroid discovery. It is named after Echo, a nymph in Greek mythology. James Ferguson had initially named it "Titania" not realizing it was already used for a satellite of Uranus.[4]

Echo has been studied by radar.[5]

References[edit]

  1. ^ a b c d e "JPL Small-Body Database Browser: 60 Echo". Jet Propulsion Laboratory. 2011-08-14 last obs. Retrieved 2012-01-27. 
  2. ^ a b Carry, B. (December 2012), "Density of asteroids", Planetary and Space Science 73: 98-118, arXiv:1203.4336, Bibcode:2012P&SS...73...98C, doi:10.1016/j.pss.2012.03.009.  See Table 1.
  3. ^ Asteroid Data Sets
  4. ^ Appletons' annual cyclopaedia and register of important events of the year: 1862. New York: D. Appleton & Company. 1863. p. 173. 
  5. ^ "Radar-Detected Asteroids and Comets". NASA/JPL Asteroid Radar Research. Retrieved 2012-01-23. 

External links[edit]