Researchers have determined that the upper atmosphere of Uranus smells like farts and rotten eggs.

Researchers from the University of Oxford used infrared light from Uranus captured by the Gemini North telescope in Hawaii to determine Uranus’ cloud tops are made up of hydrogen sulfide. Hydrogen sulfide is a toxic gas that smells like rotten eggs or passing gas.

The discovery was published by lead scientist Patrick Irwin in the April 23 issue of Nature Astronomy.

“If an unfortunate human were ever to descend through Uranus’s clouds, they would be met with very unpleasant and odiferous conditions,” said Irwin.

But the foul stench wouldn’t be the worst of it according to Irwin.

“Suffocation and exposure in the negative 200 degrees Celsius atmosphere made of mostly hydrogen, helium, and methane would take its toll long before the smell,” said Irwin.

Evidence for the presence of hydrogen sulfide gives an answer to scientists who have long debated the composition of the clouds. Some astronomers believed the gas was hydrogen sulfide, others said it was likely ammonia.