Moon Mystery

[skyatnightfan]

Hi,

I was observing the moon last night at high power.

Started at 130x and noticed a very small black vertical line at the top right of the moon.  I'm using a dob so i suppose confusingly it's the bottom left.

At first i thought this was an eyelash as that's what it looked like.  But when i moved the telescope it stayed on the moon.

I put the power up to 260x and i noticed the line was slightly bigger but it was jagged like when you see dryed up mud on the ground with cracks in it.

I've checked my scope and it's not that and I've done some research online and it's definitely not a contrail from an aircraft as i observed it over a 2hour period.

Was wandering if anyone else had come across this?

Could it be a crack in the lunar surface? 

Thanks

[stevend]

My initial reaction was that you are looking at the Straight Wall. Check some images of that out and compare. It is at its best when close to the terminator, which was on Sunday.

[michael.h.f.wilkinson]

Sounds like the straight wall. This was my shot two days ago, when it was still in the shade

It is a huge fault or escarpment on the floor of a large basin

[skyatnightfan]

That must be it! Its Definitley around the same size. Thanks for the info!

Is there only one of these on the moon, or are they quite common?

[AstroAdam]

Looks so unnatural in that field of circles!

[michael.h.f.wilkinson]

That must be it! Its Definitley around the same size. Thanks for the info!

Is there only one of these on the moon, or are they quite common?

There is only one this size, at least on this side. Smaller faults can be found, but smaller and more wiggly