This is Morning Glory Pool near Old Faithful. It is so hard to capture the beauty and colors in this scene. It's a different experience every time I photograph it.
Unfortunately, some of our natural wonders like this are being ruined by tourists. The park rangers vacuum hundreds of pounds of tourist trash out of the bottom (or source) of this pool every year. That trash lowers the temperature of the water.
Since the brilliant colors are caused by bacteria and/or algae growth that are temperature dependent (blue algae grow in hotter temperatures, brown in coolor) the vivid colors are starting to disappear. If we don't stop ruining it, our grandchildren will just see a brown pool of hot water :(