Starship Asterisk*

De58te wrote: ↑Tue Apr 04, 2023 12:53 pm Wow I have never seen such a clear picture of Olympus Mons.
This raises a question. I can see that it would be easy to climb the slopes starting at 12 to 1 o'clock, and then again at 3 to 4 o'clock but what about between 7 to 10 o'clock. There seems to be shear vertical cliffs maybe more than a thousand feet high! What caused the liquid lava flow to stop at the cliffs and not plummet over? (Although the lava did appear to flow over the cliffs in two places around 7:30 and again at 8:30.)

johnnydeep wrote: ↑Tue Apr 04, 2023 9:28 pm

George wrote: ↑Tue Apr 04, 2023 10:59 am “the slopes of Olympus Mons typically rise only a few degrees *at a time*”??

Yeah, a poor choice of words. From the WikiPedia article:

Being a shield volcano, Olympus Mons has a very gently sloping profile. The average slope on the volcano's flanks is only 5%.[15] Slopes are steepest near the middle part of the flanks and grow shallower toward the base, giving the flanks a concave upward profile. Its flanks are shallower and extend farther from the summit in the northwestern direction than they do to the southeast. The volcano's shape and profile have been likened to a "circus tent" held up by a single pole that is shifted off center.[19]

So, a 5% slope would equate to an incline angle from horizontal of 1/20 of 90 degrees, or 4.5 degrees. (Assuming that a 50% slope is 45 degrees, etc.)

George wrote: ↑Tue Apr 04, 2023 10:59 am “the slopes of Olympus Mons typically rise only a few degrees *at a time*”??

Being a shield volcano, Olympus Mons has a very gently sloping profile. The average slope on the volcano's flanks is only 5%.[15] Slopes are steepest near the middle part of the flanks and grow shallower toward the base, giving the flanks a concave upward profile. Its flanks are shallower and extend farther from the summit in the northwestern direction than they do to the southeast. The volcano's shape and profile have been likened to a "circus tent" held up by a single pole that is shifted off center.[19]

De58te wrote: ↑Tue Apr 04, 2023 12:53 pm Wow I have never seen such a clear picture of Olympus Mons.
This raises a question. I can see that it would be easy to climb the slopes starting at 12 to 1 o'clock, and then again at 3 to 4 o'clock but what about between 7 to 10 o'clock. There seems to be shear vertical cliffs maybe more than a thousand feet high! What caused the liquid lava flow to stop at the cliffs and not plummet over? (Although the lava did appear to flow over the cliffs in two places around 7:30 and again at 8:30.)