on planets that are about as close as mercury to their star often are
1st: heated up in the initial start of a stars heat from fussion and fission of hydrogen to the end resalt of helium, --- it heats the planet to burn off the water, atmosphere, and life if it ever had any.
and 2nd: it would look almost like an entire planet of lava flow since what only is left after the extreme heat is iron and other type of rock.
if the planet spins, then it would constantly cool to a solid, but then again the next day, it would be molten again!
I love astronomy! :-)