Vor einem Jahr hätte die Antwort noch Pluto lauten müssen, denn damals hatte unser Sonnensystem noch neun Planeten und Pluto war unter diesen der kleinste. Im August letzten Jahres wurde aber Pluto de ...

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 ...

The planet Neptune wobbled in its orbit around the Sun. That could only mean one thing, astronomers said: There was a ninth planet out there, somewhere, lurking in the fringes of the solar system.

Though technically not a planet, it has as rich geology as any of its planetary siblings in the solar system Shi En Kim - Reporter A color-enhanced photo of Pluto that was captured by the New Horizons ...