Vallis Alpes 31st May

[michaelmorris]

I've tried to capture this famous lunar feature on several occassions but every time I've tried, the seeing has been lousy. No different this time!

One day I'll get a descent shot of the rille on the valley floor. It's just visible on this capture, but if I can get a night of good seeing (a rather big if) I'm sure I can get a much better shot.

Best 500 frames from a capture of 2000 frames with a Mono Toucam Pro II with a Baader IR pass filter and a 2 x barlow on my 8" LX200. The seeing was bleedin' awful. Stacked in Avistack, wavelets in Regsitax with final tweaking in Photoshop/Focusmagic.

[Nick Smith]

A nice set of captures Michael, despite the less than ideal conditions. I think this is probably the best one-the central rille can be clearly seen.

Cheers

Nick

[Beulah]

Observing the moon for many years, I have always wondered what created that straight gouge. It can be very clearly seen with a telescope. Would that be caused by a meteor skimming across the surface?

[michaelmorris]

My understanding is that whilst some believe that Vallis Alpes was caused by a grazing impact, the prevailing opinion at the moment is that it's a graben - a subsistence feature where the ground on either side of the valley moves apart and the central piece of ground drops down into the cleft that is left. See the link below for a full explanation :

Graben - Wikipedia, the free encyclopedia

[Beulah]

Thanks, Michael for the explanation and link. What amazes me about this community is the precise information and excellent communication here.