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'Super-Jupiter': Giant gas planet discovered by space telescope

A photo from the space telescope of a blue-black background with a yellow-orange ball in the bottom left, and a star icon in the centreImage source, NASA, ESA, CSA, STScI, E. Matthews (Max Planck Institute for Astronomy)
Image caption,

The image, released by the James Webb Space Telescope, shows a yellow and orange circle in the bottom left corner, which is the newly discovered gas giant Eps Ind Ab. The star icon in the centre marks the location of the triple star system it is in

The James Webb Space Telescope has discovered a new planet in a triple star system only 12 light-years away from Earth.

The exoplanet - which means any planet beyond our solar system - is called Epsilon Indi Ab, or Eps Ind Ab for short.

It lives up to its status as a gas giant, with a mass more than six times the size of Jupiter, which is the biggest planet in our solar system.

The discovery of Eps Ind Ab is the first time that a planet has been 'imaged' (photographed) directly from space, without being spotted from a telescope on Earth first.

What is a gas giant?

Image source, NASA, ESA, A. Simon (Goddard Space Flight Center), And M.H. Wong (University Of California, Berkeley)
Image caption,

Jupiter is one of our solar system's gas giants - and Eps Ind Ab is even bigger

Gas giants, like Jupiter, Saturn and Eps Ind Ab, are large planets that don't have a hard crust of solid ground like the Earth has.

Instead, they're made of mostly helium gas, hydrogen gas, or both, which swirls around a solid core.

So, even if we were able to travel to Eps Ind Ab in the future, we wouldn't be able to land a spacecraft on it.

Image source, Getty Images
Image caption,

The James Webb Space Telescope is 1.5 million kilometres away from Earth, and helps scientists take photos of space that they wouldn't be able to with telescopes on the ground

What do we know about Eps Ind Ab?

There was a surprise when scientists discovered Eps Ind Ab, as it was in a different location than they first thought.

It's a very bright and cold planet, with an estimated temperature of 2 Celsius - much colder than the other gas exoplanets the James Webb Space Telescope has studied so far.

A year on Earth is how long it takes for our planet to orbit the Sun. As it takes 200 Earth years for Eps Ind Ab to orbit its star, a year would be much, much longer on the exoplanet.

Findings are still at an early stage, but scientists hope that by learning more about Eps Ind Ab can help them understand how gas planets form and change over time.