Pluto
The reclassified dwarf with a heart
Demoted from planet to dwarf planet in 2006, Pluto remains one of the most surprising worlds in the solar system. New Horizons revealed nitrogen glaciers, towering ice mountains, and a giant heart-shaped plain called Tombaugh Regio.
Image: NASA / Johns Hopkins APL / SwRI
Vital statistics
Moons
5 (Charon largest)
Gravity vs Earth
0.063 g
Day length
6.4 Earth days
Year length
248 Earth years
Diameter
2,377 km
Surface Temp
-229 °C
Did you know
Smaller than Earth's Moon.
Fact 01
Pluto and Charon are tidally locked to each other.
Fact 02
Has a thin nitrogen atmosphere that freezes in winter.
Fact 03
Deep dive
Classification
Dwarf planet, Kuiper Belt Object
Composition
Rocky core surrounded by a thick mantle of water ice and a nitrogen-methane surface.
Discovery
Discovered by Clyde Tombaugh in 1930 at Lowell Observatory.
Name origin
Named by 11-year-old Venetia Burney after the Roman god of the underworld.
Notable missions
- • New Horizons (2015 flyby)
Research & publications
Jump straight into peer-reviewed papers, preprints and authoritative references for Pluto.
arXiv (preprints)
Open-access preprints in physics & astrophysics.
NASA ADS
The definitive bibliographic database for astronomy.
Google Scholar
Cross-publisher academic search.
Nature
Peer-reviewed articles in Nature & sister journals.
Wikipedia
Encyclopedic overview & onward references.
Tip: ask the Research AI for a curated reading list → /research
