Astronomers have used a “super-telescope” to discover a violent storm raging on an alien planet some 129 light-years away from Earth. The team studied this planet, with the catchy name HR8799e, using the Very Large Telescope (VLT) in Chile.
The VLT is composed of four individual telescopes, each of which is over eight metres in diameter. These four can be used together, effectively forming one much bigger telescope.
Bigger is better when it comes to astronomy: the bigger the telescope, the sharper the image. Astronomers combine telescopes in a process known as interferometry to study objects that are too far away to observe with just one telescope.
This is the first time that optical interferometry has been used to study an exoplanet, and it revealed more detail about the HR8799e’s atmosphere than any previous observations.
“Our analysis showed that HR8799e has an atmosphere containing far more carbon monoxide than methane,” said Lacour. This is unusual since methane is created when carbon monoxide reacts with hydrogen, which is the most abundant element in the Universe.
For all of these to exist in the atmosphere together, the astronomers believe that a violent storm must be stirring up the clouds. “This paints a picture of a dynamic atmosphere of a giant exoplanet at birth, undergoing complex physical and chemical processes,” Lacour explained.
HR8799e was discovered in 2010, the fourth and innermost found around its host star, which is a young star, 129 light-years from Earth. Even without its tempestuous weather, it would be an uninhabitable planet: it is a gas giant with a temperature that soars to at least 1,000°C.