We have discovered thousands of exoplanets in the last few decades, while the number of planets ... Neptune's orbit. In a recent paper, the team looked at long-period objects that crossed the path ...

The paths of these ETNOs ... the anomalous orbits enabled Brown and Batygin to calculate the likely orbit of Planet Nine. Since then, they have been searching the part of the sky where it is ...

The number of planets that orbit the sun depends on what you mean by “planet,” and that’s not so easy to define ...

Mercury takes only 88 Earth days to orbit the sun.

Claims of a "rare planetary alignment" are misleading; it's just visible planets. A true "golden conjunction" occurs on Sept. 8, 2040.

The same year that Pluto was ignominiously stripped of its status, a paper was published theorizing that there was another planet, a very big planet, beyond Neptune. The Planet Nine theory was ...

New insights into the extreme conditions behind "disintegrating planets" reveals how they are consumed by the heat of their ...

A planet-sized visitor possibly visited the solar system billions of years ago and permanently changed the cosmic neighbourhood by warping the orbital path of four outer planets of the system, a ...