WASHINGTON (Reuters) -The universe has two kinds of matter. There is invisible dark matter, known only because of its ...

In this process, the gravitational pull of a second star in a binary system slowly disturbs the orbits of planets around the ...

Chaotic instabilities occur in hot Jupiter atmospheres as alkali metals heat up as a result of extreme temperature dynamics.

Recent flybys of the fiery world refute a leading theory of its inner structure—and reveal how little is understood about ...