直壁

C.L.Chan

直壁, 是指照片自上而下的一道黑線,早前以為是一峭壁. 後來的觀測弄清楚是一道長110km, 寬2-3km, 高240-300m的正斷層,斷層面與水平夾角約10度 . 成因是左邊雲海黑色的玄武岩漿漫蓋了一個180km直徑的無名隕坑,之後在坑中就生成這條正斷層.

Rupes Recta on the Moon, 2019/09/09 HKT: 20h47m,Telescope TEC Maksutov-Cassegrain MC200/20, D=20cm, F.L.= 400cm, LosmandyG-11 Equatorial Mount with motor drive. Camera QHY 5III 224 Color Cam,frame size 1280 x 960 px, Shoot at Gamma=112, Gain=45, Expo= 0.1ms/frame, framerate=50-107 frames/sec, avi format, stack and process 45% best frames in 4135frames,­ with Software AstroStackert 3 , wavelet with RegiStax V.6 ,   Atmospheric condition : Transparent : 8/10,Seeing : 7/10. Equipment borrowedfrom Mr. Ng. Photo taken at Kennedy Town堅尼地城, Hong Kong.