Welcome to the planet where it rains iron

Ultra-hot stuff: As massive as Jupiter but nearly twice as wide, Wasp-76b has the most extreme climate in space.

Scientists may have discovered the most extreme climate yet. This distant gas giant has exotic weather featuring heat of more than 2,000C, ultra-high winds, and iron rain!

What’s happening

Winds of over 6,000 mph howl around an inferno of hot gas. Instead of drizzling rain, droplets of molten iron condense from clouds of metal, splashing down from the dark sky deep into the atmosphere. This is a typical night on Wasp-76b, a planet in a solar system more than 640 light years away.

Find out more

The exoplanet orbits its star so closely that it takes only 43 hours for a full rotation. Dancing so near the star makes for intense heat, with temperatures high enough to boil metal.

Like our moon, Wasp-76b is tidally locked. While half of the planet is in perpetual, scorching daylight, the other lies in darkness. The resulting shifts in temperature lead to racing winds. Clouds of vaporised iron, built up in the daylight furnace, are blown around the planet where they condense in the cool darkness. Far from a refreshing shower though, the iron rain is over 1,500C.

Scientists have made the extraordinary weather report after years observing the gas giant with a high-tech telescope in Chile.

But is all this research pointless?

Some say…

Yes. Telescopes, spacecraft, and other resources are expensive. Between climate change, hunger, overpopulation, and underdevelopment, we've got enough challenges here at home, and these should take priority over exploring other worlds. While exoplanets are interesting, there is no point in learning about a planet we will never be able to visit.

Others think…

Of course not. Space exploration has led to the invention of everyday items like memory foam and satellites that provide TV and weather forecasts. Humans are naturally inquisitive, and exploring space lets us fill in pieces of a wider puzzle. Who knows, for every uninhabitable planet like Wasp-76b, there could be another with signs of life.

You Decide

  1. Would you like to go on holiday in space?


  1. Invent your own exoplanet and draw it. Think about what it is made of: rock, ice, gas? Is it habitable? What is the weather like?

Some People Say...

“I believe that space travel will one day become as common as airline travel is today.”

Buzz Aldrin (b. 1930), US astronaut

What do you think?

Word Watch

Light years
A unit of measurement equal to the distance that light travels in one year, which is 9.4607 × 1012 km. That’s nearly 6 million million miles!
A planet which orbits a star outside our solar system. In the 20 years since scientists found the first one, they have discovered over 2,000 exoplanets, all with hugely different climates.
Tidally locked
This is when one side of an astronomical body always face another. Our Moon takes just as long to rotate around its own axis as it does to revolve around the Earth. This makes one hemisphere constantly face us, so we have a light and a dark side of the Moon.
Vaporised iron
When a liquid is heated up it eventually boils and turns into vapour. Vaporised iron is blisteringly hot. The metal melts at 1538C and turns into a gas at 2862C.
The Very Large Telescope (known as VLT) is a group of four telescopes in Chile. They are extremely powerful, detecting objects roughly four billion times fainter than can be detected with the naked eye, and capable of finding planets hundreds of light years away.
A place where conditions mean it is impossible to live. Wasp-76b is uninhabitable because the high temperatures would kill us instantly, not to mention the ultra-high winds.

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