Scientists discover a Jupiter-sized exoplanet 64 light-years away that ‘reeks of rotten eggs’

There’s nothing quite as pungent as the smell of rotten eggs.

So imagine an enormous planet reeking of the stuff.

Astronomers have discovered a Jupiter-sized gas giant that contains trace amounts of hydrogen sulphide in its atmosphere.

This molecule gives off the stench of rotten eggs – even at low concentrations in the air.

But while the discovery may be a smelly one, it also offers scientists new clues about how sulphur – a building block of planets – might influence the composition of gas worlds beyond the solar system.

The planet, named HD 189733 b, is located 64 light-years away from Earth and was first detected in 2005.

It is an exoplanet, meaning it orbits a star outside of our solar system.

The giant is already infamous for its deadly weather, as it boasts a hazy, blow-torched atmosphere containing clouds laced with glass and scorching temperatures reaching 1,700 degrees Fahrenheit.

Since it is the nearest ‘hot Jupiter’ to Earth, it is a benchmark planet for detailed studies of exoplanetary atmospheres.

Researchers from Johns Hopkins University analysed data collected by the James Webb Space Telescope as part of their new study.

The planet, named HD 189733 b, is located 64 light-years away from Earth and was first detected in 2005

Infrared wavelength observations revealed the composition of the atmosphere.

Lead author Guangwei Fu said: ‘Hydrogen sulphide is a major molecule that we didn’t know was there.

‘We predicted it would be, and we know it’s in Jupiter, but we hadn’t really detected it outside the solar system.

‘We’re not looking for life on this planet because it’s way too hot, but finding hydrogen sulphide is a stepping stone for finding this molecule on other planets and gaining more understanding of how different types of planets form.

‘Sulphur is a vital element for building more complex molecules, and—like carbon, nitrogen, oxygen, and phosphate—scientists need to study it more to fully understand how planets are made and what they’re made of.’

In the coming months, Dr Fu’s team plans to track sulphur in more exoplanets and figure out how high levels might influence how close they form to their parent stars.

‘Say we study another 100 hot Jupiters and they’re all sulphur-enhanced,’ Dr Fu said.

‘What does that mean about how they were born and how they form differently compared to our own Jupiter?’

The findings were published in the journal Nature.