Corona (planetary geology)

For other uses, see Corona (disambiguation).

In planetary geology, a corona (plural: coronae) is an oval-shaped feature. Coronae appear on both the planet Venus and Uranus's moon Miranda and may be formed by upwellings of warm material below the surface.

Coronae on Venus

See also: List of coronae on Venus

Fotla Corona

On Venus, coronae are large (typically several hundred kilometres across), crown-like, volcanic features.

Coronae were first identified in 1983, when the radar imaging equipment aboard the Venera 15 and Venera 16 spacecraft produced higher resolution images of some features previously thought to be impact craters.

It is believed that coronae are formed when plumes of rising hot material in the mantle push the crust upwards into a dome shape, which then collapses in the centre as the molten magma cools and leaks out at the sides, leaving a crown-like structure: the corona.

The largest corona on Venus is the Artemis Corona, which is 2100 km in diameter.

Coronae on Miranda

See also: List of geological features on Miranda#Coronae

The small Uranian moon Miranda sports ovoid features that are very large in relation to its size. They may be formed by diapirs: upwellings of warm ice.^[1]

Notes

1. ^ R., Pappalardo; Greeley, R. (1993). "Structural evidence for reorientation of Miranda about a paleo-pole". In Lunar and Planetary Inst., Twenty-Fourth Lunar and Planetary Science Conference. Part 3: N-Z. pp. 1111–1112. http://adsabs.harvard.edu/abs/1993LPI....24.1111P. Retrieved 2006-08-05.