Pretty much everywhere! Hydrogen is the most common chemical element in the Universe, Oxygen is close behind, and they love to get together in H2O threesomes. Closer to home, there is an ocean of water under the ice on the moons of Saturn. In fact, there is so much water, that NASA is planning a mission to go there and look for life. And speaking of life, more water and water-based molecules have just been found on Mars, and on the Moon there’s far more water than anyone expected.