Diameter 40 km Colongitude 324° at sunrise | Depth 3.3 km Eponym Ole Rømer | |
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Römer is a lunar impact crater that is located to the north of the Sinus Amoris in the northeast section of the Moon. It lies in the southwestern part of the mountainous region named the Montes Taurus. To the west-northwest is the crater-bay Le Monnier, on the eastern edge of Mare Serenitatis.
The rim of Römer has relatively high walls with a terraced inner surface. There is a small craterlet on the north part of the floor, and a large central peak at the midpoint. Römer has a ray system, and due to these rays, it is mapped as part of the Copernican System.
To the northwest of the crater is a prominent system of rilles named the Rimae Römer. These follow a course to the north from the western rim of the crater, and have a combined length of about 110 kilometres.
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 Römer.
The following craters have been renamed by the IAU.