The Large Magellanic Cloud is a small galaxy, just a tenth of the Milky Way’s mass. It is about 160,000 light years away, which is remarkably close in cosmic terms. In the southern hemisphere it spans ...
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 ...