Poisson is a lunar

impact crater An impact crater is a depression (geology), depression in the surface of a solid astronomical body formed by the hypervelocity impact event, impact of a smaller object. In contrast to volcanic craters, which result from explosion or internal c ...

that is located in the southern highlands of the

Moon The Moon is Earth's only natural satellite. It Orbit of the Moon, orbits around Earth at Lunar distance, an average distance of (; about 30 times Earth diameter, Earth's diameter). The Moon rotation, rotates, with a rotation period (lunar ...

's near side. It was named after French mathematician

Siméon Denis Poisson Baron Siméon Denis Poisson (, ; ; 21 June 1781 – 25 April 1840) was a French mathematician and physicist who worked on statistics, complex analysis, partial differential equations, the calculus of variations, analytical mechanics, electricity ...

. It lies to the east of the crater Aliacensis and northwest of

Gemma Frisius Gemma Frisius (; born Jemme Reinerszoon; December 9, 1508 – May 25, 1555) was a Dutch physician, mathematician, cartographer, philosopher, and instrument maker. He created important globes, improved the mathematical instruments of his day ...

. To the northwest of Poisson is Apianus. This heavily eroded crater shares a common floor with the satellite crater Poisson T to the west-southwest, and the two craters have more or less merged into a single formation with a narrower neck in between. The rim of Poisson is heavily eroded, and is overlain by several craters. Poisson U is intruding into the southern rim at the junction of Poisson and Poisson T. A low-walled formation is joined to the northern rim at the opposite side of the neck from Poisson U. The interior floor of Poisson and Poisson T has been resurfaced by

basalt Basalt (; ) is an aphanite, aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the planetary surface, surface of a terrestrial ...

lava Lava is molten or partially molten rock (magma) that has been expelled from the interior of a terrestrial planet (such as Earth) or a Natural satellite, moon onto its surface. Lava may be erupted at a volcano or through a Fissure vent, fractu ...

, leaving a level surface within the inner walls. A pair of old, worn craters lies along the inner wall in the southeast part of the crater.

Satellite craters

By convention these features are identified on lunar maps by placing the letter on the side of the crater midpoint that is closest to Poisson.

References

* * * * * * * * * * * {{Commons category Impact craters on the Moon