Clyde Tombaugh discovered Pluto in 1930 at Lowell Observatory in Flagstaff. Here's how Pluto won - and lost - its planetary ...

Why was Pluto reclassified as a dwarf planet? One might think that it’s purely a matter of size. Mercury, the smallest of the ...

Scientists occasionally refer to Charon and Pluto as a double dwarf planet system. Up close, Charon is striking. The satellite is covered in crevices that scientists think may harbor a liquid ocean.

“New Horizons shattered a major paradigm of planetary science,” says Alan Stern, the mission’s principal investigator. “Pluto turns out to have as much complexity as Mars or Earth, so much so that I ...

A blue atmosphere, smooth areas, and youthful mountain ranges - this dwarf planet is full of surprises. When NASA's New Horizons probe flew past Pluto in July 2015, the images it returned astonished ...

Famously, Pluto no longer met the criteria and was demoted to a dwarf planet ... Earth was considered a planet in its own ...

For one reason or another, some people are still upset about Pluto's demotion from planet to dwarf planet. This demotion, by the way, occurred all the way back in 2006. So, what does famed ...

An curved arrow pointing right. NASA's New Horizons spacecraft took us to Pluto for the first time in July 2015. Scientists are astonished by the incredible features they've observed on the dwarf ...

The dwarf planet was there ... by New Horizons is that of Pluto’s "heart" feature. The heart-shaped glacier, nicknamed Sputnik for Earth’s first human-made satellite, is nearly 600 miles ...

The newly-spotted dwarf planet joins a cohort of other small worlds in that part of space, including Pluto. Together, dwarf planets can help scientists learn a lot about how the solar system ...

The Moon is a natural satellite that orbits planet Earth ... The Earth has just one moon - the Moon. Pluto is a dwarf planet. As the name suggests, a dwarf planet is smaller than a planet.