Water is Life. It’s a bold, dramatic claim that appears to be true for all known organisms here on Earth. Take a sip. Take a deep breath. Take a look around. Everything you see, touch, taste, smell, has water in some form.

Thirsty yet? Well, pack your canteen, because we’re going on an intergalactic water hunt. And most of this water you’re not going to be able to drink.

Whether or not we care about drinkability depends on the reason we’re looking for water. If we want to live somewhere, it must have water. And not in just any form either. Liquid water is the prerequisite for most life as we know it. That means that when we are looking for life on other planets, we are searching for signs of water.

While liquid water is the cornerstone of the search for life and habitable homes outside of our Earth, the different states of water (ice and gas) have quite a bit to tell us about the universe. But let’s start at the very beginning, before water was liquid, gas, or solid. Before it was even water.

Take your “First Step” below.

About The Author

Madelyn Broome

Madelyn was the 2018 Editor-in-Chief of Innovation, and a former writer and editor for the Space/Physics section. Her piece "Where's the Water?" won the 2019 Gregory T. Pope Prize for Science Writing. She is passionate about science communication and about making science engaging and accessible for people of all ages - though she especially enjoys working to ignite excitement for the sciences in young girls and other underrepresented communities in STEM. When she's not trying to share her enthusiasm for the sciences, she can usually be found exploring, practicing mixed martial arts, archery, lifting, playing soccer, or just generally trying to make up for the dessert she just ate.