Mike Brown is convinced that beyond Neptune, at the far reaches of our solar system, there's an unseen giant planet. "This is the 5th largest planet in our solar system, lurking out there, waiting to ...

Does our Solar System have 9 planets or only 8? Astronomers have gone back and forth on that a lot, with Pluto now being classified as a dwarf planet. However, out beyond Neptune there could be ...

HOUSTON — Stargazers will have a special treat this weekend with a planetary parade of seven planets. If the weather cooperates, you should be able to see some of them without any fancy equipment.

DALLAS — Get ready, North Texas! This evening, Feb. 28, a celestial event that showcases the big names in our galaxy: Our planets. A seven-planet parade will be visible from the big North Texas skies.

NEW YORK — Six planets grace the sky this month in what's known as a planetary parade, and most can be seen with the naked eye. These planetary hangouts happen when several planets appear to line up ...

If the object really is Planet Nine, it would be larger than Neptune and exist 700 times further from the sun than Earth. The best candidate yet for the elusive Planet Nine has been spotted in two ...