The Solar System's first-of-its-kind finding may be a 90% water planet. Is the dwarf planet, Ceres, holding the possibility ...

Stargazers will be treated to a rare alignment of seven planets on 28 February when Mercury joins six other planets that are already visible in the night sky. Here's why it matters to scientists.

Beginning in late February, seven planets will align in the night sky. But Uranus and Neptune may require a telescope to see. Mars SKY AT Viewed from above the solar system, the seven planets will ...

But we're yet to prove that, not in small part because of our inability to directly observe the rocky planets residing in their solar system's habitable zones. A habitable zone is a rather small ...