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Theophilus (crater)
Encyclopedia
Theophilus is a prominent lunar impact crater
that lies between Sinus Asperitatis
in the north and Mare Nectaris
to the southeast. It partially intrudes into the comparably sized crater Cyrillus
to the southwest. To the east is the smaller crater Mädler
and further to the south-southeast is Beaumont
. It was named after the 4th century Greek
philosopher Theophilus.
The rim of Theophilus has a wide, terraced inner surface that shows indications of landslips. It is 14,000 feet deep with massive walls and has broken into a second formation, Cyrillus
. It was created during the Eratosthenian
period, from 3.2 to 1.1 billion years ago. It has an imposing central mountain, 1,400 meters high, with four summits.
The floor of the crater is relatively flat, and it has a large, triple-peaked central crater that climbs to a height of about 2 kilometers above the floor. The western peak is designated Psi (ψ), the eastern Phi (φ), and the northern peak is Alpha (α) Theophilus. The western slopes of this ridge are wider and more irregular, whereas the peaks descend more sharply to the floor on the northern and western faces.
The Apollo 16
mission collected several pieces of basalt
that are believed to be ejecta from the formation of Theophilus.
Impact crater
In the broadest sense, the term impact crater can be applied to any depression, natural or manmade, resulting from the high velocity impact of a projectile with a larger body...
that lies between Sinus Asperitatis
Sinus Asperitatis
Sinus Asperitatis is an area of lunar mare that extends southward from the Mare Tranquillitatis until it joins the Mare Nectaris to the southeast. It is bordered along the western and eastern sides by continental regions of irregular terrain...
in the north and Mare Nectaris
Mare Nectaris
The Sea of Nectar is a small lunar mare or sea located between the Sea of Tranquillity and the Sea of Fecundity . Montes Pyrenaeus borders the mare to the west and the large crater near the south center of the mare is known as Rosse...
to the southeast. It partially intrudes into the comparably sized crater Cyrillus
Cyrillus (crater)
Cyrillus is a lunar impact crater located on the northwest edge of Mare Nectaris. Intruding into the northeast rim is the equally large, and younger crater Theophilus. To the south is another prominent crater named Catharina. Together these three craters form a prominent trio in the southeast...
to the southwest. To the east is the smaller crater Mädler
Mädler (lunar crater)
Mädler is a lunar impact crater located on the mare that joins Sinus Asperitatis in the north to Mare Nectaris to the southeast. To the west is the prominent crater Theophilus, and Mädler lies amidst the outer rampart....
and further to the south-southeast is Beaumont
Beaumont (crater)
Beaumont is a lava-flooded crater located on the southwestern shore of the Mare Nectaris on Earth's Moon. It lies to the northwest of the similarly flooded crater remnant Fracastorius. To the west is the prominent crater Catharina....
. It was named after the 4th century Greek
Greece
Greece , officially the Hellenic Republic , and historically Hellas or the Republic of Greece in English, is a country in southeastern Europe....
philosopher Theophilus.
The rim of Theophilus has a wide, terraced inner surface that shows indications of landslips. It is 14,000 feet deep with massive walls and has broken into a second formation, Cyrillus
Cyrillus (crater)
Cyrillus is a lunar impact crater located on the northwest edge of Mare Nectaris. Intruding into the northeast rim is the equally large, and younger crater Theophilus. To the south is another prominent crater named Catharina. Together these three craters form a prominent trio in the southeast...
. It was created during the Eratosthenian
Eratosthenian
The Eratosthenian period in the lunar geologic timescale runs from 3,200 million years ago to 1,100 million years ago. It is named after the crater Eratosthenes, whose formation marks the beginning of this period. The formation of the crater Copernicus marks its end, and the beginning of the...
period, from 3.2 to 1.1 billion years ago. It has an imposing central mountain, 1,400 meters high, with four summits.
The floor of the crater is relatively flat, and it has a large, triple-peaked central crater that climbs to a height of about 2 kilometers above the floor. The western peak is designated Psi (ψ), the eastern Phi (φ), and the northern peak is Alpha (α) Theophilus. The western slopes of this ridge are wider and more irregular, whereas the peaks descend more sharply to the floor on the northern and western faces.
The Apollo 16
Apollo 16
Young and Duke served as the backup crew for Apollo 13; Mattingly was slated to be the Apollo 13 command module pilot until being pulled from the mission due to his exposure to rubella through Duke.-Backup crew:...
mission collected several pieces of basalt
Basalt
Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey...
that are believed to be ejecta from the formation of Theophilus.
Satellite craters
By convention these features are identified on lunar maps by placing the letter on the side of the crater mid-point that is closest to Theophilus.| Theophilus | Latitude | Longitude | Diameter |
|---|---|---|---|
| B | 10.5° S | 25.2° E | 8 km |
| E | 6.8° S | 24.0° E | 21 km |
| F | 8.0° S | 26.0° E | 13 km |
| G | 7.2° S | 25.7° E | 19 km |
| K | 12.5° S | 26.3° E | 6 km |
| W | 7.8° S | 28.6° E | 4 km |