A recently discovered celestial body is rewriting our knowledge of the Kuiper Belt and maybe challenging the existence of the ...

The small world was found during a search for the hypothetical Planet Nine, and astronomers say the next time it will reach ...

The newly discovered object, named 2017 OF201, has a 25,000-year orbit and is believed to be a large contender for dwarf ...

However, as scientific understanding evolved, so did Pluto's classification — though not without controversy. Pluto fails the ...

Pluto came into the lexicon in 1930 when astronomer ... also concurred that dwarf planets and planets are two distinct classifications. They determined the Solar System contains eight planets ...

There’s a new frozen oddball orbiting the Sun, and it’s not your average space rock. It’s a planet—a minor one, to be ...

And so this argument, I think that doesn't hold much water. So classification wise, I am completely comfortable calling Pluto a planet, the moon a planet. BARBER: Europa, one of Jupiter's moons ...

calling into question Pluto’s classification. As a result, in 2006, the International Astronomical Union (IAU) voted to adopt new requirements for planetary status—kicking Pluto out of the ...