Kerwan () is the largest confirmed crater and one of the largest geological features on Ceres. It was discovered on February 19, 2015 from ''
Dawn
Dawn is the time that marks the beginning of twilight before sunrise. It is recognized by the appearance of indirect sunlight being scattered in Earth's atmosphere, when the centre of the Sun's disc has reached 18° below the observer's hori ...
'' images as it approached Ceres. The crater is distinctly shallow for its size, and lacks a central peak. A central peak might have been destroyed by a 15-kilometer-wide crater at the center of Kerwan. The crater is likely to be young relative to the rest of Ceres's surface, as Kerwan has largely obliterated the cratering in the southern part of
Vendimia Planitia.
[Marchi, S et al. “The missing large impact craters on Ceres.” Nature communications vol. 7 12257. 26 Jul. 2016, doi:10.1038/ncomms12257]
Kerwan is roughly antipodal to
Ahuna Mons
Ahuna Mons () is the largest mountain on the dwarf planet and asteroid Ceres. It protrudes above the cratered terrain, is not an impact feature, and is the only mountain of its kind on Ceres. Bright streaks run top to bottom on its slopes; these ...
, the largest, or at least youngest, mountain on Ceres. Seismic energy from the Kerwan-forming impact may have focused on the opposite side of Ceres, fracturing the outer layers of the crust and facilitating the movement of high-viscosity
cryomagma (consisting of muddy water ice softened by its content of salts) onto the surface.
Kerwan too shows evidence of the effects of liquid water due to impact-melting of subsurface ice.
The crater is named after the
Hopi spirit of sprouting maize, Kerwan. The name was approved by the
IAU
The International Astronomical Union (IAU; french: link=yes, Union astronomique internationale, UAI) is a nongovernmental organisation with the objective of advancing astronomy in all aspects, including promoting astronomical research, outreach ...
on July 3, 2015.
[
]
See also
*List of geological features on Ceres
Ceres is a dwarf planet in the asteroid belt that lies between the orbits of Mars and Jupiter. The IAU has adopted two themes for naming surface features on Ceres: agricultural deities for craters and agricultural festivals for everything else.
...
References
{{Ceres
Impact craters on asteroids
Surface features of Ceres