After a decade-long search, some scientists say a growing number of clues point to the existence of a hidden planet in the ...

A ninth planet may exist beyond Neptune in the Kuiper Belt, a region populated by icy bodies that orbit the Sun.

The solar system has nine planets, but in 2006 the International Astronomical Union declared Pluto a dwarf planet, making the ...

It’s often called Planet X or Planet Nine. “If we find another planet, that is a really big deal,” said Malena Rice, an assistant professor of astronomy at Yale University. “It could ...

近年来，越来越多的证据表明太阳系边缘可能潜藏着一颗未被发现的大质量天体，其引力影响着柯伊伯带天体的运行轨迹，甚至可能与海王星特殊的自转轴倾角有关。这颗神秘天体被称为“行星九”（Planet ...

The search for Planet Nine, a hidden world beyond Neptune, is heating up as scientists prepare to use a powerful new telescope.

Scientists speculate if Planet Nine is a new planet or a primordial black hole. Discoveries could redefine our understanding ...

The race could come down to seven pivotal battleground states, and we might not know the winner tonight, so be patient and follow our live updates. 1️⃣ Planet Nine? Scientists say a growing number of ...

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 ...

Indiana University of Pennsylvania’s Cejka Planetarium in John J. and Char Kopchick Hall will host two programs during the ...