Try visiting the Sunrise area in summer when the milky way aligns perfectly with Mount Rainier making it appear as though the volcano is erupting galactic beauty.
This trail seems like something out of Lord of the Rings with sweeping views practically the entire way, not just of the mountain itself but breathtaking alpine scenery.
From the top of the trail you'll be able to see Mount Rainier in all its glory and the Paradise area to the north, and Mt Adams in the distance to the south.