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Airy-0

Airy-0
Three images of Airy-0 taken by, from A to C, Mariner 9, Viking 1 and Mars Global Surveyor.
Three images of Airy-0 taken by, from A to C, Mariner 9, Viking 1 and Mars Global Surveyor. Airy-0 is the larger crater towards the top center in each frame.
Planet Mars
Region Inside Airy Crater
Coordinates 5°06′S 0°00′E / 5.1°S 0°E / -5.1; 0Coordinates: 5°06′S 0°00′E / 5.1°S 0°E / -5.1; 0
Diameter 0.5 kilometres (0.31 mi)
Eponym Sir George Biddell Airy

Airy-0 is a crater on Mars whose location defines the position of the prime meridian of that planet. It is about 0.5 kilometres (0.31 mi) across and lies within the larger crater Airy in the region Sinus Meridiani.

It was named in honor of the British Astronomer Royal Sir George Biddell Airy (1801-1892), who in 1850 built the transit circle telescope at Greenwich. The location of that telescope was subsequently chosen to define the location of Earth's prime meridian.

Merton Davies chose this crater as Mars's prime meridian in 1969 based on Mariner 6 and 7 photographs.


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