Last year, astronomers discovered an unusual Earth-size exoplanet they believe has a hemisphere of molten lava, with its ...

Astronomers have peered through the atmosphere of a planet beyond the Solar System, mapping its 3D structure for the first time. By combining all four telescope units of the European Southern ...

Saturn, Venus, Neptune, Uranus, Jupiter, Mars and Mercury will be visible in an uncommon planetary alignment this month.

For a brief moment at the end of February, every planet will appear in the night sky simultaneously in a rare celestial ...

Planet demographics reveal a puzzling lack of worlds in a certain size range throughout the galaxy F or centuries our solar system was the only planetary system known to humans. We had no proof other ...

Venus reached its maximum brightness on Valentine's Day this year, creating a luminous spectacle in the sky over St. Petersburg, Russia.

Although the occurrence climaxed on Jan. 21 with a conjunction—close alignment—of Saturn and Mercury, the planetary parade ...