Masursky as seen by Cassini with identification arrow
|Discovered by||Edward L. G. Bowell|
|Discovery date||3 May 1981|
|1950 VO; 1973 QF;
1975 XJ5; 1977 KU;
|Main belt (Eunomia family)|
|Epoch 13 January 2016 (JD 2457400.5)|
|Uncertainty parameter 0|
|Observation arc||15469 days (42.35 yr)|
|Aphelion||2.85094 AU (426.495 Gm)|
|Perihelion||2.28780 AU (342.250 Gm)|
|2.56937 AU (384.372 Gm)|
|4.12 yr (1504.3 d)|
Average orbital speed
|Earth MOID||1.3315 AU (199.19 Gm)|
|Jupiter MOID||2.2439 AU (335.68 Gm)|
|~2.7 g/cm³ (estimate)|
Equatorial surface gravity
Equatorial escape velocity
max: 264 K (−9° C)
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. Because 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. The asteroid was between 0.81 and 1.08 arcseconds in apparent 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.
- "JPL Small-Body Database Browser: 2685 Masursky (1981 JN)". Jet Propulsion Laboratory. Retrieved 25 March 2016.
- 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; et al. (1999). "The Eunomia Family: A Visible Spectroscopic Survey". Icarus 142 (2): 445. Bibcode:1999Icar..142..445L. doi:10.1006/icar.1999.6213.