October 12, 2014
southeast up image by Pavel Presnyakov, Kiev Ukraine
Petavius is one of the most striking craters on the Moon. And this low sunsetting illumination (complementing Pavel's sunrise image) dramatically exhibits a multitude of floor features. The big trench is obviously most unique with nothing else on the Moon comparable; its origin is still uncertain. The main mass of central peaks is relatively standard, but lower Sun views and LRO altimetry show that the center of the crater floor is domed up. The elevated area is bounded by the rough ring of hills. Between these hills and the rim is a low-lying moat with smoother terrain. The smoothness is because volcanic domes, pits and rilles in the moat erupted ash that veneers the area. The rim of Petavius has two very unusual features. Although the eastern and northern portions of the rim are normal, the southwestern and less obviously the southeastern parts are broad and flat. A second unique feature of the rim is the railway track-like rille that crosses the flat part of the rille and then continues more than 300 km as the Hase Rille. Finally, south of Petavius is a series of smooth-surfaced ponds of old impact melt.
Newt 350 mm + barlow 5x + IR 650 + Basler sca1600 + WS-180 mount.
21st Century Atlas chart 4.
Yesterday's LPOD: Something Borrowed, Something New
Tomorrow's LPOD: Joining the Sisters