Growing up, I was taught that there were nine planets in the solar system. That all changed in 2006, when the International Astronomical Union voted to demote Pluto's status to that of dwarf planet.

In 2016, Batygin and Brown first outlined in detail how the orbits of six of these objects could be explained by a specific Planet Nine. They predicted this world must have a mass at least 10 ...

Known as Planet Nine or Planet X, it is a hypothetical planet that has long been rumoured to exist in the outer solar system. Although "several claims to have found an extra planet have been made ...

That incredibly vague and unsatisfying idea is the sum total of what scientists have been able to tell us about the mysterious “Planet Nine,” and it doesn’t look like we’re getting any ...

Have you ever wondered what it takes to journey to Mars? A one-way trip to the Red Planet would take nine months but a return journey would be around three years. While these estimates provide a ...

Scientists have observed a huge planet approximately nine times the mass of Jupiter at a remarkably early stage of formation, describing it as still in the womb, in a discovery that challenges ...

Planet Nine, a massive icy world, may be lurking at the outer edge of our solar system, awaiting discovery by advanced telescopes. "It's really difficult to explain the solar system without Planet ...