#mare imbrium

Copernicus crater on the right is one of the larger craters on the Moon and is easily visible with some binoculars. This crater was named after none other than Nicolaus Copernicus (1473-1543), the Polish astronomer who came up with the Sun-centered model of the solar system, popularized after his death.

Eratosthenes crater on the left is another large crater. It is older than nearby Copernicus. This crater is named after the Greek astronomer Eratosthenes of Cyrene (276-194 BC) who is famous for calculating the circumference of the Earth to a very accurate degree!

Also here is Gay-Lussac crater, just below Copernicus. It is named after the French chemist Joseph Louis Gay-Lussac (1778-1850) who discovered that water is two parts hydrogen and one part oxygen.

Seen as a ghostly outline at the top is Stadius crater, an ancient crater that has been flooded with lava flows. It is named after the Flemish astronomer Johannes Stadius (c. 1527-1579) who published a table of planetary positions, called ephemerides.

Finally, these craters are bounded by the Mare Imbrium ("Sea of Showers") to the south and Sinus Aestuum ("Seething Bay") to the north.