729 Watsonia

729 Watsonia

Discovery
Discovered by	Joel Hastings Metcalf
Discovery site	Winchester, Massachusetts
Discovery date	9 February 1912
Designations
Alternative names	1912 OD
Orbital characteristics[1]
Epoch 31 July 2016 (JD 2457600.5)
Uncertainty parameter 0
Observation arc	98.79 yr (36082 d)
Aphelion	3.0270 AU (452.83 Gm)
Perihelion	2.4917 AU (372.75 Gm)
Semi-major axis	2.7594 AU (412.80 Gm)
Eccentricity	0.096988
Orbital period	4.58 yr (1674.2 d)
Mean anomaly	223.02°
Mean motion	0° 12^m 54.108^s / day
Inclination	18.042°
Longitude of ascending node	124.388°
Argument of perihelion	88.376°
Earth MOID	1.56567 AU (234.221 Gm)
Jupiter MOID	2.17725 AU (325.712 Gm)
Jupiter Tisserand parameter	3.264
Physical characteristics
Mean radius	24.575±0.75 km
Rotation period	25.230 h (1.0513 d)
Geometric albedo	0.1381±0.009
Absolute magnitude (H)	9.31

729 Watsonia is a minor planet orbiting the Sun. It was named after the Canadian-American astronomer James C. Watson. Asteroid (729) Watsonia occulted the star HIP 53417 (54 Leonis A/B, 4.3 Magnitude Star) on 2013 Mar 03 at 01:48.

This object is the namesake of a family of 31–139 asteroids that share similar spectral properties and orbital elements; hence they may have arisen from the same collisional event. All members have a relatively high orbital inclination.^[2]

References

1. Yeomans, Donald K., "729 Watsonia", JPL Small-Body Database Browser (NASA Jet Propulsion Laboratory), retrieved 5 May 2016.
2. Novaković, Bojan; et al. (November 2011), "Families among high-inclination asteroids", Icarus 216 (1), pp. 69–81, arXiv:1108.3740, Bibcode:2011Icar..216...69N, doi:10.1016/j.icarus.2011.08.016.

External links

• Discovery Circumstances: Numbered Minor Planets
• 729 Watsonia at the JPL Small-Body Database

• Discovery · Orbit diagram · Orbital elements · Physical parameters