Petavius (crater)
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| Crater characteristics | |
|---|---|
| Coordinates | 25.3° S, 60.4° E |
| Diameter | 177 km |
| Depth | 3.4 km |
| Colongitude | 300° at sunrise |
| Eponym | Denis Petau |
Petavius is a large lunar impact crater located to the southeast of the Mare Fecunditatis, near the southeastern lunar limb. Attached to the northwest rim is the smaller Wrottesley crater. To the southeast are Palitzsch crater, Vallis Palizsch, and Hase crater. Further to the north is the large Vendelinus crater. The crater Petavius appears oblong when viewed from the Earth due to foreshortening.
The outer wall of Petavius crater is unusually wide in proportion to the diameter, and displays a double-rim along the south and west sides. The height of the rim varies by as much as 50% from the lowest point, and a number of ridges radiate outward from the rim. The convex crater floor has been resurfaced by lava flow, and displays a rille system named the Rimae Petavius. The large central mountains are a prominent formation with multiple peaks, climbing 1.7 kilometers above the floor. A deep fracture runs from the peaks toward the southwest rim of the crater.
Rev. T. W. Webb described Petavius as,
- "one of the finest spots in the Moon: its grand double rampart, on east side nearly 11,000 ft. High, its terraces, and convex interior with central hill and cleft, compose a magnificent landscape in the lunar morning or evening, entirely vanishing beneath a Sun risen but halfway to the meridian."
The most favorable time for viewing this feature through a telescope is when the Moon is only three days old. By the fourth day the crater is nearly devoid of shadow.
70cm radar images of this crater and its surroundings show that the region of the surface beyond the wide outer rampart of Petavius has a dark halo, characteristic of a smooth surface free of boulders. It is thought that this may have been created by radial outbursts during the original impact that swept the area "clean".
Crater Petavius B to the north-northwest of Petavius has a small ray system that lies across the Mare Fecunditatis surface.
[edit] 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 Petavius crater.
| Petavius | Latitude | Longitude | Diameter |
|---|---|---|---|
| A | 26.0° S | 61.6° E | 5 km |
| B | 19.9° S | 57.1° E | 33 km |
| C | 27.7° S | 60.1° E | 11 km |
| D | 24.0° S | 64.4° E | 17 km |
[edit] References
- Wood, Chuck (December 12, 2006). Trenchent Observations of a Trench. Lunar Photo of the Day. Retrieved on December 12, 2006.
- Wood, Chuck (February 21, 2007). The Hase-Petavius Rille. Lunar Photo of the Day. Retrieved on February 21, 2007.
- Rev. T. W. Webb, Celestial Objects for Common Telescopes, rev. 6, Dover, 1962, ISBN 0-486-20917-2.
- Ghent and others, Properties of Lunar Crater Ejecta from New 70-cm Radar Observations, 2004, Lunar & Planetary Science 35; #1879.
- See the reference table for the general listing of literature and web sites that were used in the compilation of this page.
[edit] External links
- LPOD — A New Kind of DHC, by Charles A. Wood.
