17 Thetis

Infobox Planet | discovery=yes | physical_characteristics = yes | bgcolour=#FFFFC0
name=17 Thetis
discoverer=R. Luther
discovered=April 17, 1852
alt_names=A913 CA; A916 YF; mp|1954 SO|1
mp_category=Main belt
epoch=October 22, 2004 (JD 2453300.5)
semimajor=369.530 Gm (2.470 AU)
perihelion=319.991 Gm (2.139 AU)
aphelion=419.069 Gm (2.801 AU)
eccentricity=0.134
period=1418.027 d (3.88 a)
inclination=5.587°
asc_node=125.622°
arg_peri=135.906°
mean_anomaly=38.435°
avg_speed=18.87 km/s
dimensions=90 km
mass=7.6e|17 kg
density=2.0? g/cm³
surface_grav=0.0252 m/s²
escape_velocity=0.0476 km/s
rotation=0.5113 d (12.27 h) [ [http://www.astrosurf.com/aude-old/map_files/AstVarMAP01-2003.htm] Dead link|date=March 2008]
spectral_type=S
abs_magnitude=7.76
albedo=0.1715 [ [http://www.psi.edu/pds/archive/astdata04/simps04/diamalb.tab] Dead link|date=March 2008]
single_temperature=~173 K

17 Thetis (pronEng|ˈθiːtɪs, _gr. "Θέτις)" is a large Main belt asteroid. It is a S-type asteroid, therefore giving it a relatively bright silicate surface.

It was discovered by R. Luther on April 17, 1852. It was his first asteroid discovery. Its name comes from Thetis, the mother of Achilles in Greek mythology.

One Thetidian stellar occultation was observed from Oregon in 1999. However, the event was not timed.

References