Pictures of Uranus

A guide to the icy ringed giant, and images captured by astrophotographers.

Uranus by Voyager 2

Uranus isn’t much to look at. When Voyager 2 flew past the planet in 1986, it found a uniform ball that is tinted sky blue by methane in the atmosphere. But looking beyond the calm exterior reveals a planet where winds blow at speeds in excess of 900km/h, in the wrong direction.

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While most planets’ spin axes are at right angles to their orbits, Uranus has been knocked over onto its side.

No one is entirely certain why, but the lead theory is that an Earth-sized planetoid collided with Uranus early in the Solar System’s history, tipping it over.

Keck image of Uranus
Uranus is surrounded by a thin ring, seen here in infrared images from the Keck telescope.
Lawrence Sromovsky, University of Wisconsin-Madison/W.W. Keck Observatory

However, Uranus isn’t always as calm as when Voyager 2 spied on it.

As the planet takes 85 years to orbit the Sun, the seasons last for decades and the probe passed by during the planet’s northern summer.

When Uranus passed into autumn in 2007, long-range observations found the planet seemed to wake up, with storms creating bright spots the size of North America in the planet’s atmosphere.

Uranus also has rings.

Facts about Uranus

  • Diameter: 50,724km (3.98 times Earth)
  • Mass: 86.8 trillion trillion kg (14.5 times Earth)
  • Distance from the Sun: 2872 million km (19.2 AU)
  • Length of day: 17.2 hours
  • Length of year: 83.8 years
  • Number of moons: 27
  • Average temperature: -195ºC
  • No of spacecraft visitors: 1
  • Type of planet: Ice giant

How to observe Uranus

Uranus with Umbriel, Titania, Arial and Oberon by Harvey Scoot, Essex, UK. Equipment: C14 Edge HD, ZWO120MMS, Baader 610nm Long Pass filter.
Uranus with Umbriel, Titania, Arial and Oberon by Harvey Scoot, Essex, UK. Equipment: C14 Edge HD, ZWO120MMS, Baader 610nm Long Pass filter.

With a dark sky and good eyesight, it should just be possible to make out Uranus with the naked eye when it is at opposition (when it’s positioned in the opposite part of the sky to the Sun). For more on this, read our guide How to see Uranus.

For the best views, however, you should use a telescope. Uranus should begin to become clear with an aperture of at least 3 to 4 inches and a magnification of 100x to 150x.

At these high magnifications, your observations may be affected by a phenomenon known as seeing, where the turbulence in Earth’s atmosphere causes the image to shimmer.

Experiment with different eyepieces, a Barlow lens and focal extenders to find the best magnification on any given night. It is possible to take a photograph of the planet’s disc, but its distance from Earth makes doing so something of a challenge.

How was Uranus discovered?

While Uranus is just about visible with the naked eye, it is so dim and moves so slowly that ancient astronomers overlooked it.

After the invention of the telescope, several astronomers did spot the planet, but it was only when William Herschel observed it in 1781 that its true origin became apparent.

He first reported his sightings as a potential comet, and later recognised it as a planet.

Why is it called Uranus?

Hubble image of Uranus
Recent images of Uranus taken by Hubble show the ice giant now has light coloured bands, and a dark spot which could be a storm.
NASA/Space Telescope Science Institute

The planet was initially named George, in honour of the English king at the time who’d given Herschel a grant in recognition of hid discovery. The name was understandably unpopular outside of Britain.

In 1782, German astronomer Johann Bode suggested Uranus after the roman god of the sky and father of the Titans, which would blend in better with the other planets.

The moons, meanwhile, were named by William Herschel’s son, John, who decided to name them after characters from English literature (most from Shakespeare).

The trend has continued as more moons are discovered.

How should you pronounce Uranus? The planet’s name has become something of a joke in recent years, leading some to wonder how to say the planet’s name without causing giggles or smirks. Generally speaking, astronomers pronounce Uranus as YOOR-aniss, with the stress on the first syllable.

What missions have explored Uranus?

Uranus as photographed by Voyager 2 in 1986. The view is towards the planet's pole of rotation captured from 18 million km away. The left image is in the original colours that a human would see looking from the spacecraft. To the right, false-colours exaggerate a potential polar haze of smog-like particles. (Credit: NASA/JPL)
Uranus as photographed by Voyager 2 in 1986. The view is towards the planet’s pole of rotation captured from 18 million km away. The left image is in the original colours that a human would see looking from the spacecraft. To the right, false-colours exaggerate a potential polar haze of smog-like particles. (Credit: NASA/JPL)

So far only one mission has visited Uranus, Voyager 2, which flew past the planet in 1986. The mission showed Uranus was an almost featureless green-blue ball.

In the years since, telescopes on Earth and in orbit have improved to the point where they can now take detailed images of the planet, allowing us to make out the changing weather on its surface.

It seems that the planet’s upper atmosphere has become much more varied since then, suggesting that we happened to fly past the planet during a particularly calm point in Uranus’s climate cycle.

Uranus missions

  • Voyager 2 (1986, NASA)

Pictures of Uranus

Below is a selection of images captured by astrophotographers and BBC Sky at Night Magazine readers. For more info on astro imaging, read our guide on how to photograph planets or our beginner’s guide to astrophotography.

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Uranus with Moons by Luke Oliver, Grays, UK. Equipment: Skywatcher 200P, ZWO ASI120MC, 2x Barlow
Uranus with Moons by Luke Oliver, Grays, UK. Equipment: Skywatcher 200P, ZWO ASI120MC, 2x Barlow
A Uranian Family by Harvey Scoot, Braintree, UK. Equipment: C14 Edge HD, ZWO120MMS with 610nm longpass filter.
A Uranian Family by Harvey Scoot, Braintree, UK. Equipment: C14 Edge HD, ZWO120MMS with 610nm longpass filter.
Uranus and Satellites by Marc Delcroix, Tournefeuille, France. Equipment: 320mm SkyVision Newton, x2 barlow, R+IR 610nm filter, ZWO ASI290MM camera
Uranus and Satellites by Marc Delcroix, Tournefeuille, France. Equipment: 320mm SkyVision Newton, x2 barlow, R+IR 610nm filter, ZWO ASI290MM camera
Planet Uranus by Avani Soares, Parsec Observatory, Canoas, Brazil. Equipment: C14 Edge, ASI 224, PM 2X, Red filter 610 nm
Planet Uranus by Avani Soares, Parsec Observatory, Canoas, Brazil. Equipment: C14 Edge, ASI 224, PM 2X, Red filter 610 nm
Uranus with Four of the Family by Ralph Smyth, Lisburn, County Antrim. Equipment: Celestron C8 SCT, ZWO ASI224MC, ASI290MM , Skywatcher HEQ5Pro Mount
Uranus with Four of the Family by Ralph Smyth, Lisburn, County Antrim. Equipment: Celestron C8 SCT, ZWO ASI224MC, ASI290MM , Skywatcher HEQ5Pro Mount
Uranus by Fernando Oliveira De Menezes, Sao Paulo. Equipment: C11 Edge HD, Powermates
Uranus by Fernando Oliveira De Menezes, Sao Paulo. Equipment: C11 Edge HD, Powermates