Back in 2006 our Solar System lost a planet, not because it disappeared, but because it was reclassified. Pluto, now considered a dwarf planet, failed one of the three tests the International ...

He called this hypothetical world "Planet X." "In some ways, Pluto's more of a planet than some of the other established planets, like Mercury." Lowell dedicated years to predicting the location ...

He called this hypothetical world "Planet X." "In some ways, Pluto's more of a planet than some of the other established planets, like Mercury." ...

It takes Pluto slightly over 248 Earth years to orbit the sun, which means that on March 23, 2178, one Plutonian year will have elapsed since the dwarf planet was first spotted, on Feb.

If you answered "Pluto's planethood," your grasp of the astronomical is excellent. Feb. 18 marks the 95th anniversary of the discovery of our outermost planet-not-planet. Here's what to know about ...

Pluto was discovered at Lowell Observatory in Flagstaff, Arizona in 1930 and was considered our ninth planet until 2006. The International Astronomical Union reclassified Pluto as a dwarf planet ...

Pluto, discovered in 1930, was once considered the ninth planet in our solar system. In 2006, the International Astronomical Union reclassified Pluto as a dwarf planet because it doesn't meet all ...

They did, and the discovery of Planet X was announced on March 13, 1930. An 11-year-old English schoolgirl, Venetia Burney, suggested the name Pluto, the god of the underworld. Tombaugh’s ...

"The data from the termination shock encounter will be a treasure trove for space physicists worldwide who are eager to ...