Crazy Crater?

[Kropster]

Evening All

I took this rough photo of the Lunar terminator a couple of night ago using my phone held to the eyepiece(!).

I was amazed by the brightness of a small ring just inside the dark part and had to get photo.

I expected a crater to appear as a semicircle or perhaps two facing each other as the sunlight catches the top of the ridges, but not a continuous very bright ring.

Probably been seen many times by experienced observers.

Is this crater unusual?

Steve

[Laurie61]

Hi Steve, looks like you spotted T Mayer A crater.

During local sunrise (morning terminator), the entire rim of T. Mayer A is illuminated by the sun, creating some sort of remarkable "ring"-effect.

[Kropster]

So, not an alien moonbase after all, then!

Thanks Laurier61.