Why is water vital to life?
Why is water vital to life?
When astronomers search for life outside of our solar system, they look right past the gas giants like Saturn and Jupiter, past the torrid, rocky planets like Mercury and Venus, and past the dwarf planets like Pluto. They stop when they find an exoplanet like Gliese 581d. Gliese 581d is about 50 percent larger than Earth, and like Earth, it orbits in what's known as a star's habitable zone, the stellar sweet spot where a planet is capable of having liquid water. And where there's water, there might, just possibly, be life.
What makes scientists think that water is better at sustaining life than every other substance?
