Earth, between sweltering Venus and frozen Mars, formed and orbits within a band where water could persist in solid, liquid, and gaseous phases. Mars had surface water, but not as much as Earth, and ...

Astronomers have identified the largest and most distant water reservoir ever detected in the universe. This immense ...

Astronomers have discovered two galaxies that are perfectly aligned, allowing their combined gravitational pull to act as a compound lens.

This advertisement has not loaded yet, but your article continues below. The more than 100 carriers that fly to Israel in peacetime have been winnowed down to fewer than a dozen, giving Israeli ...