How far away is Pluto right now?

5,340,097,300

kilometres · Pluto's distance from Earth

About 36 times the distance from Earth to the Sun.
An airliner at cruising speed would take 672 years to cover it.

Right now Pluto is in the evening sky, after sunset. You need a large telescope to see it.

Right now Pluto is about 5.3 billion kilometres from Earth, and the gap changes every second. A radio message, moving at the speed of light, needs 4.9 hours to cross it.

Pluto circles the Sun far beyond Neptune, so its distance from us swings between 4.3 billion and 7.5 billion kilometres. Since 2006 astronomers have called it a dwarf planet. The next close approach is on 26 July 2027.

Time until Pluto's next close approach to Earth

268 d 09 h 05 m 20 s

Measured

Length of one turn of Pluto (sidereal day)

6.4 days

Measured

Number of known moons of Pluto

Measured

Average surface temperature of Pluto

-232 °C

Estimated

What is Pluto?

A small world at the edge

Pluto is a world of ice and rock that circles the Sun far beyond Neptune. Clyde Tombaugh found it in 1930. A schoolgirl in Oxford, Venetia Burney, suggested its name.

It is small. Earth is about 5.4 times as wide, and about 155 worlds the size of Pluto would fit inside it. Even our Moon is about 1.5 times as wide as Pluto, and about 5.6 times as heavy.

Pluto lives in the Kuiper Belt. This is a wide ring of icy bodies beyond Neptune, left over from when the planets formed. Many small frozen worlds share it. Pluto is the best known of them.

Its path round the Sun is an oval, tilted against the planets' paths. On average Pluto is about 39 times as far from the Sun as Earth is. At its nearest it comes inside Neptune's orbit: from 1979 to 1999, Pluto was closer to the Sun than Neptune.

2,376 kmEquatorial diameter of Pluto

24 August 2006

Why Pluto is called a dwarf planet

From 1930 to 2006, Pluto was called the ninth planet. Then astronomers began finding similar icy worlds farther out in the Kuiper Belt. Either all of them were planets, or the word needed a clearer meaning.

On 24 August 2006, in Prague, the International Astronomical Union voted. A planet, it decided, must do three things. It goes round the Sun. It has enough mass for its own gravity to pull it into a nearly round shape. And it has cleared the neighbourhood around its orbit.

Pluto passes the first two tests. It fails the third: it shares its zone with the crowd of the Kuiper Belt. So the IAU made it a dwarf planet, round and in orbit round the Sun, but not alone in its lane. Ceres, in the asteroid belt, became one on the same day.

Not everyone agrees. In 2017 a group of planetary scientists, including Alan Stern, proposed a geophysical definition. In it, a planet is any round body smaller than a star, wherever it orbits. By that measure Pluto, Charon, Ceres and our Moon are all planets. The IAU definition is the one in use.

39.4817 AUPluto's average distance from the Sun

The next close approach

Why the distance keeps changing

Earth and Pluto both circle the Sun, like runners on a very large track. Earth runs a tight inside lane in a year. Pluto, far out, needs about 248 Earth years for one lap.

So Earth catches up with Pluto about once a year, every 1.00 years on average. Each time, Earth passes between the Sun and Pluto, and the two come closest. Half a year later Earth is on the far side of the Sun, and the gap has grown by the whole width of Earth's orbit.

There is a slower change too. Pluto is still moving outward along its oval, towards its farthest point from the Sun. For the rest of this century, each close approach is a little farther than the one before.

The clock on this page counts down to the next close approach, on 26 July 2027.

268 d 09 h 05 m 20 sTime until Pluto's next close approach to Earth

Right now

A hello that takes hours

Radio waves are a kind of light, and nothing travels faster. Even so, a message to Pluto takes 4.9 hours to arrive today. Sunlight reaches us in about 8.3 minutes. To get to Pluto, it needs about 5.5 hours.

Even at its nearest, Pluto stays 4.3 billion kilometres away, so the wait is always hours long.

That light is faint. At noon on Pluto, NASA says, the Sun is about as bright as our sky in the moment near sunset on Earth. Even so, it is still far brighter than a full Moon.

Only one spacecraft has made the trip. NASA's New Horizons flew past Pluto on 14 July 2015. Its pictures came home slowly, a little at a time, across this same gap. The New Horizons page tells that story.

5,340,097,301 kmPluto's distance from Earth

A double world

Charon and the other moons

Pluto has 5 known moons. The largest, Charon, was found in 1978. Pluto is only about 2 times as wide as Charon. No other moon is so large next to the world it circles, NASA says. The two are often called a double planet.

A day on Pluto, from one sunrise to the next, lasts 6.4 days: that is how long Pluto takes to turn once. Charon goes round Pluto in that same time. So each keeps the same face to the other. From one side of Pluto, Charon hangs still in the sky and never sets. From the other side, it is never seen.

Pluto spins backwards, too, and lies tipped over on its side.

The four other moons are small and lumpy: Nix, Hydra, Kerberos and Styx. They spin as they go, and none keeps one face towards Pluto. Like Pluto and Charon, they are named for the underworld of the old myths.

5Number of known moons of Pluto

The cold

A heart of ice

The most famous feature on Pluto is a bright, heart-shaped region about 1,600 kilometres across. Its western half is a vast plain of frozen nitrogen. New Horizons saw it clearly for the first time in July 2015. NASA says the plains show signs of convection: blobs of ice slowly rising and sinking.

Pluto is very cold. On average the temperature there is -232 °C, against 15 °C on Earth. Nitrogen, the gas that makes up most of our air, lies frozen solid on its plains.

Pluto has air of its own, all the same. It is thin, mostly nitrogen with a little methane and carbon monoxide. NASA says it swells when Pluto comes nearer the Sun. Far out along its oval, much of it may freeze and fall to the ground as snow.