Masursky as seen by Cassini with identification arrow
|Discovered by||Edward L. G. Bowell|
|Discovery date||May 3, 1981|
|Named after||Harold Masursky|
|Alternative names||1950 VO; 1973 QF;
1975 XJ5; 1977 KU;
|Minor planet category||Main belt (Eunomia family)|
|Epoch July 14, 2004 (JD 2453200.5)|
|Aphelion||426.737 Gm (2.853 AU)|
|Perihelion||341.603 Gm (2.283 AU)|
|Semi-major axis||384.170 Gm (2.568 AU)|
|Orbital period||1503.127 d (4.12 a)|
|Average orbital speed||18.53 km/s|
|Longitude of ascending node||215.437°|
|Argument of perihelion||289.057°|
|Mean density||~2.7 g/cm³ (estimate)|
|Equatorial surface gravity||0.006–0.007 m/s²|
|Escape velocity||0.009–0.012 km/s|
max: 264K (-9° C)
|Absolute magnitude (H)||12.2|
The asteroid 2685 Masursky is a main-belt asteroid. It was discovered by Edward (Ted) Bowell in 1981. It was named after Harold Masursky (1923–1990), a planetary geologist at the U.S. Geological Survey, Flagstaff, who worked on numerous space missions.
Little was known about Masursky until the Cassini space probe, en route to Jupiter and Saturn, flew past it on 23 January 2000. Since Cassini passed the asteroid at a distance of 1.6 million kilometres (about four times the Earth–Moon distance), the images it returned showed nothing more than a dot. Nevertheless, Cassini was able to determine Masursky's size (about 15–20 km in diameter). 
Masursky's orbit places it within the Eunomia family of S-type asteroids. Cassini's observations had cast some doubt on its composition, but later ground-based spectroscopy has confirmed its S-type spectrum.
- G. A. Krasinsky et al. Hidden Mass in the Asteroid Belt, Icarus, Vol. 158, p. 98 (2002).
- NASA/JPL. "PIA02449 info page". Retrieved 19 July 2013.
- D. Lazzaro, T. Mothé-Diniz, J. M. Carvano, C. A. Angeli, A. S. Betzler, M. Florczak, A. Cellino, M. Di Martino, A. Doressoundiram, M. A. Barucci, E. Dotto, P. Bendjoya (1999). "The Eunomia Family: A Visible Spectroscopic Survey". Icarus 142 (2): 445. Bibcode:1999Icar..142..445L. doi:10.1006/icar.1999.6213.