- 140 Siwa
Infobox Planet | discovery=yes | physical_characteristics = yes | bgcolour=#FFFFC0
name=140 Siwa
discoverer=Johann Palisa
discovered=October 13 ,1874
alt_names=
mp_category=Main belt
epoch=December 31 ,2006 (JD 2454100.5)
semimajor=408.817 Gm (2.733 AU)
perihelion=320.360 Gm (2.141 AU)
aphelion=497.275 Gm (3.324 AU)
eccentricity=0.216
period=1650.076 d (4.52 a)
inclination=3.187°
asc_node=107.292°
arg_peri=197.230°
mean_anomaly=156.165°
avg_speed=17.80 km/s
dimensions=109.8 km
mass=1.4e|18 kg
density=? g/cm³
surface_grav=0.0307 m/s²
escape_velocity=0.0580 km/s
rotation=? d
spectral_type=P
abs_magnitude=8.34
albedo=?
single_temperature=~168 K140 Siwa (pronEng|ˈʃiːwə?) is a large and dark
main belt asteroid . It has a composition of a P (or possibly C-type) asteroid. It was discovered by J. Palisa onOctober 13 ,1874 and named afterŠiwa , the Slavic goddess offertility . Siwa has a very flat lightcurve, indicating a spherical body.The "Rosetta"
comet probe was to visit Siwa on its way to comet46P/Wirtanen in July,2008 . However, the mission was rerouted to comet67P/Churyumov-Gerasimenko and the flyby had to be abandoned.
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