Pluto’s heart-shaped feature, known as Tombaugh Regio, has captivated scientists and the public alike since its discovery.

The debate over Pluto’s planetary status has been ongoing since its reclassification as a “dwarf planet” in 2006 by the ...

With a diameter of 1,440 miles, Pluto is farthest from the sun. While major planets make roughly circular orbits, Pluto ...

Tombaugh's widow and two children offered up an ounce of his ashes for the journey to Pluto. The ashes of the farm boy-turned-astronomer are in a 2-inch aluminum capsule inscribed with these words: ...

Pluto, discovered 90 years ago on Feb. 18, 1930, was long considered the solar system's ninth planet, but was relegated to dwarf planet status in 2006.

New Horizons has been carrying science instruments on its 3 billion mile, nine-and-a-half year journey to Pluto, and an ounce of the astronomer's ashes have also been along for the ride.

The science community may be ecstatic over the discovery of a ninth planet, but the former planet "Pluto" had a totally different reaction. Hours after scientists announced there's solid evidence ...

CAPE CANAVERAL, FL -- Come Tuesday, Clyde Tombaugh will pass within 7,800 miles of the icy world he discovered 85 years ago. His ashes are flying on NASA's New Horizons spacecraft on humanity's ...