Is there a massive undiscovered planet on the outer reaches of the solar system? The idea has been around since before the ...

What can lava planets, rocky exoplanets that are tidally locked and orbit so close to their stars that the intense heat melts ...

A new paper led by a York University professor and published today in Nature Astronomy introduces a simple theoretical ...

A team of astronomers led by Macquarie University has monitored the orbital decay of an extreme exoplanet to gain new ...

The research suggests that wide-orbit planets (such as Planet X) arise in the early evolution of their planetary systems, when these systems are still inside their stars' crowded birth clusters.

Its two known planets, including 14 Her c, orbit at angles of about 40 degrees to each other, creating an "X"-like crossing pattern around their star.

Normally, planets orbit in roughly the same plane as their host stars. Most of the 16 known circumbinary planets—that is, planets that orbit two stars—follow this coplanar rule.

The Very Large Telescope in Chile has found, for the first time, an infant planet nestled in spiral arms of dust around a ...

NEW YORK — A new Tatooine-like planet outside the solar system may orbit two failed stars, scientists reported Wednesday. Located about 120 light years away, the exoplanet appears to take an ...

A new Tatooine-like planet outside the solar system may orbit two failed stars, scientists reported Wednesday.Located about 120 light years away, the exoplanet ...

The International Astronomical Union reclassified Pluto as a dwarf planet because it does not clear its orbit of other debris. Pluto was the little planet that could — until it couldn’t.