The Straight Wall

[bkm2304 (Richard Brown)]

Hi All,

Straight Wall (Rupes Recta), taken on the 24th September. Also known as Huygen's Sword. Above it is Birt after the 19th Century English Selenographer and offsider to John Herschel; Lassell after William, the English amateur rich guy who discovered Triton, Hyperion, Ariel and Umbriel; Purbach after the 15th Century Austrian Astronomer and inventor; La Caille, the French Abbe who catalogued 10,000 southern stars and gave names to faint patches of sky like Telescopium and Horologium to represent the enlightenment and progress; Thebit after Iraqi medieval astronomer; Arzachel after the Spanish medieval astronomer; Alpetragius another Spanish/Moorish medieval astronomer; Alphonsus after yet another Spanish Moor Astronomer from the 13th Century.

22" Newtonian, DMK21, stack of 450 from 2,500 images. The seeing was excellent!

Great shots of Rupes Recta and surrounds from Selene are here.
Richard

[Larryp (Laurie)]

Great images!

[DJDD]

thansk for interesting write-up, too.

[SkyViking (Rolf)]

Great image of this fascinating structure

[alistairsam]

Hi,
Silly question, but I know craters are concave and it takes a while for the brain to transform it from convex to concave, but these craters look convex to me no matter how I look at them.
Is it me or are they really convex, like plateau's?

edit : ok finally got it by staring at the small crater around 9 O'clock and then all of them appear concave, but it reverts back quickly. must be the age catching up!!

[bkm2304 (Richard Brown)]

Thanks all for the comments. . Yes, Alistsair, when I first see craters on the imaging screen they almost always look concave to me. I have to move my eyes around fast until they reorient. Quite pleasant but also disconcerting!

Richard

[Matt Wastell (Matt)]

Look at the image upside down - it changes again!

Originally Posted by alistairsam

Hi,
Silly question, but I know craters are concave and it takes a while for the brain to transform it from convex to concave, but these craters look convex to me no matter how I look at them.
Is it me or are they really convex, like plateau's?

edit : ok finally got it by staring at the small crater around 9 O'clock and then all of them appear concave, but it reverts back quickly. must be the age catching up!!