Why clink glasses in a hot tub when you could take a dip in the Grand Prismatic Spring? Located in Yellowstone National Park, this hot spring puts bath bombs to shame with its bright bands of orange, yellow, green and blue that come from the different species of heat-loving bacteria living in the water.

Okay, so it may be way too hot for us humans, but the microbes living here have led scientists to some major medical advances, including the sequencing of the entire human genome. They’re also giving NASA clues about extraterrestrial life on seemingly inhospitable planets.

At 370 feet in diameter, the Grand Prismatic Spring is the third largest of its kind in the world and boasts sizzling temperatures of 70 degrees Celsius.