A new study has confirmed what a number of scientists have long suspected about the ice giant planet, Uranus.

Its upper atmosphere probably smells like rotten eggs.

Uranus taken by Voyager (Photo: NASA/JPL)

Photo of Uranus, taken by Voyager (Photo: NASA/JPL)

The rotten egg smell can be attributed to a flammable and poisonous gas called hydrogen sulfide.

An international group of scientists led by Patrick Irwin, from the UK’s University of Oxford, conducted what they describe as sensitive spectroscopic observations of the 7th planet from the Sun.

They used the Gemini North telescope’s Near-Infrared Integral Field Spectrometer (NIFS) located on the summit of Hawaii’s dormant volcano, Mauna Kea.

By splitting apart infrared light from Uranus, the astronomers found and confirmed the presence of noxious hydrogen sulfide gas swirling high in the giant planet’s cloud tops.

The study detailing the group’s findings has been recently published in the journal, Nature Astronomy.