I have a question regarding the words 上る and 上がる. One of the example sentences of the word “sun” is “そろそろ日がのぼるじかんだ。” which is translated here as “It is time for the sun to rise.” But isn’t the word “上がる” actually translated as “to rise”? So the question is, why 上る is used here and not 上がる? And will it be correct to use the latter in this sentence then? By the way, i know that 上る has meaning "to go up"as well, but it’s not really the same as “to rise”, is it not?