The cosmos is filled with wonders yet to be discovered. One of the latest mysteries captivating scientists and space ...

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." ...

Caltech researchers have mathematical evidence suggesting a Neptune-sized Planet X may exist deep in the solar system in an orbit far beyond Pluto. Planet X could have a mass about 10 times that of ...

Pluto was discovered in 1930 by Clyde Tombaugh ... which came to be called Planet X. Lowell searched for this elusive planet, but he died in 1916 having never found it. Using a tool called ...

He searched for Planet X from 1905 until his death in 1916, without luck. It would take another generation before the observatory, aided by the patient Tombaugh, would at last have success. The 95 ...

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 ...

Pluto, with its heart-shaped glacier ... looking for the elusive world known at that point only as Planet X. Percival Lowell, the astronomer and businessman who built the observatory, had long ...

which he called "Planet X." Years after his death, Tombaugh used a blink comparator to analyze photographic plates of the night sky, eventually spotting Pluto. Today, visitors can explore Lowell ...

Pluto, discovered in 1930 ... which came to be called Planet X. Using a tool called a blink comparator, Tombaugh finally found the mysterious body in 1930. The machine involved taking pairs ...