Fejokoo (crater)

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Fejokoo Crater
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An image of Fejokoo and surrounding terrain. Fejokoo is the hexagonal crater to the upper left, with its unusual shape likely sculpted by rim landslides
Feature typeCentral-peak impact crater
LocationFejokoo Quadrangle, Ceres
Coordinates29°9′N 47°53′W / 29.150°N 47.883°W / 29.150; -47.883[1]
Diameter~68 km[1]
Depth~5 km[2]
DiscovererDawn
EponymFejokoo

Fejokoo is a hexagonal impact crater on the dwarf planet Ceres. Like all craters on Ceres, it is named after an agricultural deity; the crater is named for the Igbo deity who provided yams. The name was officially approved by the International Astronomical Union (IAU) on 3 July 2015, shortly after Dawn had entered Ceres orbit.[1] Fejokoo Crater is the namesake for the Fejokoo Quadrangle.[3]

In contrast to typical craters, which are circular or elliptical in shape, Fejokoo resembles an equilateral hexagon and is the largest polygonal crater on Ceres. As with most large craters on Ceres, Fejokoo's floor is generally flat and bounded by a very steep rim, with slopes exceeding 45° in some sections. The floor is roughly 5 kilometers deep; the floor is interrupted at the center of Fejokoo by a cental peak roughly 1 kilometer high.[2] The polygonal shape of Fejokoo likely comes from mass wasting processes such as landslides from the crater rim; the eastern and western rims are particularly affected, containing terraced landslide material.[3][4] The surface composition of Fejokoo is overall typical of Ceres, though bright streaks on its northern wall and near its central peak appear to be enriched in ammonia and hydroxides.[4]

References

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  1. ^ a b c "Fejokoo". Gazetteer of Planetary Nomenclature. USGS Astrogeology Research Program. (Center Latitude: 29.15°, Center Longitude: 312.11°; Planetocentric, +East)
  2. ^ a b Hughson, K. H. G.; Russell, C. T.; Williams, D. A.; et al. (December 2018). "The Ac-5 (Fejokoo) quadrangle of Ceres: Geologic map and geomorphological evidence for ground ice mediated surface processes". Icarus. 316: 63–83. Bibcode:2018Icar..316...63H. doi:10.1016/j.icarus.2017.09.035.
  3. ^ a b Hughson, Kynan; Russell, Christopher; Williams, David; et al. (March 2016). Geological Mapping of the Ac-H-5 Fejokoo Quadrangle of Ceres from NASA's Dawn Mission (PDF). 47th Lunar and Planetary Science Conference. The Woodlands, Texas, United States. Retrieved 30 April 2024.
  4. ^ a b Singh, S.; Combe, J. -P; McFadden, L. A.; et al. (January 2019). "Mineralogy mapping of the Ac-H-5 Fejokoo quadrangle of Ceres". Icarus. 318: 147–169. Bibcode:2019Icar..318..147S. doi:10.1016/j.icarus.2018.08.025.