UKC

20 foot mount mercou on Mars. What grade would the crack up the middle be? What adjustment to grade for the lack of breathable atmosphere and sub zero temps? Do you think anyone would mind if it got bolted?

https://twitter.com/mars_stu/status/1373792251902590978?s=20

Is that chalk below the overhang? As for bolting what does the local BMC rep have to say?

Looks a tempter. Would it come within the 'stay local' travel guidance? 

Looks like sandstone so you'd have to enquire about the local ethics on placing gear. Top rope or the Czech method of rope knots perhaps.

It's probably about 2 inches high - no scale in the photo

It’s about 6 meters high apparently. 

Well, the Local Group contains a number of galaxies and Mars is not only in the same galaxy as us in that group, it's also in the same star system, so I'd say you are definitely safe classing it as "local"

OK, and thanks

Only if you can get home the same day