Pluto

Once the 9th planet in the Solar System, Pluto is now classified as a Kuiper Belt Object. Credit: NASA/JHUAPL/SwRI

Observing guide Can you find Pluto in the night sky?

Image of Pluto taken by New Horizons

Radio Astronomy Podcast Pluto at 90: how Clyde Tombaugh discovered a new world

Once the 9th planet in the Solar System, Pluto is now classified as a Kuiper Belt Object. Credit: NASA/JHUAPL/SwRI

Astronomy explained Why is Pluto not a planet?

Clyde Tombaugh pictured at a Zeiss Blink Comparator, a machine used in the discovery of Pluto. Credit: Lowell Observatory Archives

Astronomers you should know Clyde Tombaugh

Image of Pluto taken by New Horizons

What’s warming Pluto’s icy heart?

Remote observations have suggested that Ultima Thule has a lumpy shape, or could even be two bodies in orbit around each other. Image Credits: NASA/JHUAPL/SwRI/Steve Gribben

Interview: Ramy El-Maarry, New Horizons scientist

An artist's illustration of New Horizons at Pluto. Credit: Image Credit: Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute

What did New Horizons discover at Pluto?

The diversity of Pluto’s surface is visible in this shot, showing the various surfaces and landforms on the dwarf planet. This 350km wide image shows cratered terrain, mountains and a field of dark ridges that look like dunes.

New Horizons reveals latest Pluto images

Astronomer James Christy pictured with the photographic plate on which he and Robert Harrington discovered Pluto’s largest moon Charon, in 1978. Credit: U.S. Naval Observatory

How Pluto’s moon Charon was discovered

Voyager 2's view of Triton. Credit: NASA/JPL/USGS

The Story of the Solar System: Geysers on Triton

Dune-like features can be seen in Sputnik Planitia, which scientists believe were caused by thermal winds transporting grains of methane ice. Credit: NASA/JHUAPL/SwRI

Ice dunes discovered on Pluto

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New Horizons: ice volcanoes and spinning moons

An image of Pluto captured in high-resolution by NASA’s New Horizons spacecraft on 14 July 2015. The spacecraft studied the dwarf planet before beginning its journey towards MU69. Credit: NASA/JHUAP/SwRI

New Horizons phones home

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Pluto’s icy mountains revealed

New Horizons images of Pluto's largest moon, taken on 11 July 2015, reveal chasms, craters and a dark polar region.
Credit: NASA/JHUAPL/SWRI

New Horizons reveals Charon’s surface features