The disappointed Germans kept looking and in 1802 found another one ... Although Pluto's orbit was more elongated than the other planets' (and even crossed the orbit of Neptune—not the kind ...

(CNN) -- German astrophysicists have concluded a space body located in the outer reaches of the solar system has a diameter 435 miles (700 kilometers) larger than Pluto, the smallest planet.

He soon became fascinated by another cosmic mystery ... Pluto's more of a planet than some of the other established planets, ...

Pluto's bright, refractive surface meant that it was easier to spot in mid-century telescopes than many other Kuiper Belt ...

Pluto was discovered in 1930 in Arizona, but in 2006 scientists decided to cut Pluto from the planetary line up. Here is why Pluto isn't a planet.

Discover the order of planets in the solar system. From Mercury to Neptune, explore our solar system and learn more about our cosmic home. The solar system is our cosmic neighborhood, made up of ...

Brown is the person who discovered Eris, a 10th solar system object that's about 27% more massive than Pluto ... criteria - in other words, they're definitely dwarf planets and not comets or ...

is probably more about the astronomers doing the looking than ... nine planets, which came about in the 1960s and lasted only until 2006, was a blip on the screen. And if you are still a Pluto ...

and Pluto is smaller than Earth's moon. For years, astronomers tried to define a planet by shape, orbit around a star and its influence on other bodies. But they couldn't agree. In 2000 ...