Hokusai (crater)

Hokusai is a rayed impact crater on Mercury, which was discovered in 1991 by ground-based radar observations conducted at Goldstone Observatory.^[2] The crater was initially known as feature B. Its appearance was so dissimilar to other impact craters that it was once thought to be a shield volcano. However, improved radar images by the Arecibo Observatory obtained later in 2000–2005 clearly showed that feature B is an impact crater with an extensive ray system. The bright appearance of rays in the radio images indicates that the crater is geologically young; fresh impact ejecta has a rough surface, which leads to strong scattering of radio waves.^[2]

Hokusai

Photo of Hokusai by MESSENGER
Feature type	Peak-ring impact basin
Location	Hokusai quadrangle, Mercury
Coordinates	58.3°N 342.3°W / 58.3; -342.3
Diameter	95 km (59 mi)
Eponym	Katsushika Hokusai[1]

Hokusai is named after Katsushika Hokusai (1760–1849), a Japanese artist and printmaker of the Edo period.^[3][1] The name Hokusai was suggested by radar astronomer John K. Harmon.^[4] The crater has a diameter of about 100 km; the rays extend for thousands kilometers, covering much of the northern hemisphere.^[5]

Hokusai is the fourth-largest crater of the Kuiperian system on Mercury. The largest is Bartók crater.^[6] Hokusai is one of 110 peak ring basins on Mercury.^[7]

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  The rays of Hokusai crater (near central horizon) extend across much of the planet
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  The ray system close to the crater
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  MESSENGER WAC image

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  Mosaic of MESSENGER NAC images
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  Another mosaic of the interior