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

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

The Solar System is a fascinating place, with each planet orbiting the Sun at its own unique distance. But how far apart are ...

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

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 new planet’s odd orbit sets it apart. But it hasn't been directly spied, and scientists say more research is needed to be sure it's out there and figure out its mass and orbit.

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 ...