The three lowest-density exoplanets yet discovered may be steps on the planetary evolution ladder, shrinking to resemble more commonplace worlds over time.
Peering into the heart of the Milky Way with a powerful infrared camera, astronomers see evidence for a titanic burst of star formation in the relatively recent past.
A five-year study shows water is a relatively common component of exoplanet atmospheres, but the observed abundances are less than expected, researchers say.