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dwarf planet · Kuiper belt

Pluto

Best-known dwarf planet, icy/rocky, famous heart-shaped plain, visited by New Horizons.

🕒 When can I see it?🚀 Travel there

What it is

Dwarf planet: Round, but shares its orbit with other rubble. Every kind of thing there is →

How to find Pluto

Its position moves, so there is no fixed place on a map to point at. The Planetarium works out where it is for your own place and date.

What you will really see

Through a small telescope, on a good night

A faint point of light — a star chart across several nights shows it moving.

Honest, not glamorous — why the pictures here are drawn.

🔭 See it drawn as it looks through a telescope

Worth knowing about Pluto

Pluto is about 1/6 the size of Earth. In weight, very light -- about 1/500th of Earth. About 40 times Earth's distance from the Sun. Sunlight takes 5.5 hours to reach Pluto — on average, because that distance changes as it goes round. Pluto was found in 1930, and it will not finish that first observed lap around the Sun until 2178. Its day: 6.4 Earth days.

Its surface
Icy and rocky, nitrogen-ice glaciers, water-ice mountains, famous heart-shaped plain (Tombaugh Regio).
The machines we sent
New Horizons flew by in 2015, taking the first close-up pictures ever.
The numbers
Across2 377 km
Distance from the Sun, on average39 AU ~5.9 billion km · sunlight takes 5.5 hours
Once round its orbit247.9 Earth years
One day there6.4 days
Temperature-229 °C (from -233 to -223)
Made of, among other thingsnitrogen, methane, water

How anyone knows this

Nobody flew a tape measure out there. Every number on this page was worked out from the ground:

What it belongs to

☀️ Everything the Sun holds, in one place

Then go outside

Clear tonight? The Planetarium will show you what is worth a look. Then just go out.

🌙 Plan an evening outside🌌 Everything else in the sky