roughly the size of Arizona from north to south. Pluto was discovered in 1930 by Clyde Tombaugh while he worked at Lowell Observatory in Flagship, Arizona. Sputnik Planitia is a white basin ...

In 2006, the IAU determined Pluto did not meet the qualifications to be a planet because it doesn’t clear its orbital path like the other planets do. Mercury’s diameter is bigger than dwarf ...

And so on May 1, Lowell Observatory announced that Planet X would be named Pluto. But with its peculiar, tilted orbit and confoundingly small size, the world remained an enigma. Over the years the ...

Neither one is “big.” Earth’s moon is 2,160 miles in diameter. Some scientists believe Pluto should be upheld, but others suggest that Pluto, UB313 and other icy denizens of the Kuiper Belt ...

When the International Astronomical Union announced in 2006 that Pluto was being demoted from its status as the Sun's ninth ...

Compared to Valles Marinensis, the Grand Canyon of Colorado is tiny, measuring 446 kilometers long, with a maximum width of ...

Using a phenomenon known as gravitational lensing, it might be possible to use the sun as a gigantic telescope to peer deep ...

Venus, Jupiter, Saturn, Neptune and Pluto all have quasi-moons which will eventually change their paths and leave orbit. Even ...

About the same size and shape as a grand piano, New Horizons travels 300,000 miles per year, faster than any other man-made object. Having launched from Earth in 2006 and photographed dwarf Pluto ...

The satellite is the smallest of Pluto's moons. Charon, the largest, is more than 640 miles in diameter. The new moon is located in the orbit between satellites Nix and Hydra.

Venus is about the same size as the Earth ... it was not born in orbit around Neptune—it was sort of like a Pluto that was captured by Neptune. It's got a really interesting magnetic field ...

In recent years, Pluto’s ad bidding process has caused many agencies to pay what they feel is too much based on the ...