A

ejecta blanket Cross-section of Copernicus

Diameter A = 93 km Height of central peaks C = 1200 m Depth of floor B ~ 3700 m Height of outer walls D = UOOm

Small imped craiers (diameter less than about 15 km) do not have central peaks. They tend to have simple bowl shape whereas in a large crater like Copernicus, slumping of material off the inner walls helps to flatten the crater floor Note also that B is greater than D, (Not to scale) and the inner walls are always steeper than the outer ejecta blanket.

Image T219:

Eratosthenes 11.30 W 14.50 N An impact crater between Copernicus and the south end of Montes Apenninus, 58 km in diameter and 3600 m deep. It has a sharp rim, terraced walls and 3 central peaks. Eratosthenes changes in appearance during a lunation. At full moon it almost disappears. The lack of bright rays around the crater suggests that the rays were washed out by space weathering, so Eratosthenes must be older than Copernicus and is determined to have formed 3.2 billion years ago (the beginning of the Eratosthenian period). The adjacent land relief is interesting; it resembles an elephant with an upward swirling nose.

Stadius 13.70 W 10.50 N

A ghost depression with incomplete low walls, 69 km in diameter. It is peppered with secondary craterlets and pits. A L-shaped feature (possibly composed of a catena and a rille) extends from the southeast rim. The height of the northeast wall is 650 m.

Eratosthenes 2005.04.18 11:53UT Age 9.6 days. 10-in »6+4X «ToUcan 95% resized.

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Monies Carpatus & Copernicus 2005.04.19 13:40UT Age 10.7 days. 10-infffi Newtonian + 2.5X + ToUcam

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