* Astronomy

Vallis Alpes (formerly known as the Alpine Valley), a sinuous rille about 166 km long and 8 km wide, is visible on the 12th April, 2012.The feature is visible as a narrow cut through the Montes Alpes mountain range east of crater Plato.
It is visible even in small telescopes.

The selenographic coordinates of this feature are 48.5°N 3.2°E. The valley floor is a flat, lava-flooded surface that is bisected by a slender, cleft-like rille. (This cleft is a challenging target for telescope observation from the Earth.)
This valley was discovered in 1727 by Francesco Bianchini.
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The valley floor is a flat, lava-flooded surface that has narrow sinous 'rille' running down the middle. It is generally considered to be a 'graben', an area between two parallel faults which has dropped below the surrounding area. This is believed to have formed after the formation of the basin, but before the full maria lava flows. The rille corresponds to a 'lava tube' formed in a later geological episode by high-speed and low viscosity magma.
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