Researchers have used a special astronomy technique, called optical interferometry, to study the atmosphere of an exoplanet roughly 129 light-years from Earth. This is the first direct detection of an exoplanet using this method and it has revealed that this distant world is being thrashed by a global storm.
HR8799e, as the planet is known, is completely inhospitable. It’s a super-Jupiter weighing between five and 10 times the mass of the Solar System’s gas giant. It is only 30 million years old, a baby planet in cosmic terms. Despite not having anything like it in our Solar System, this object could provide us with insights into the formative years of planets.
This planet still has leftover energy from its formation and for this reason, it is really hot. HR8799e glows red with a temperature of roughly 1,000°C (1,800°F). As reported in Astronomy & Astrophysics, its extreme characteristics give rise to complex atmospheric phenomena, including a planet-wide storm.
“Our observations suggest a ball of gas illuminated from the interior, with rays of warm light swirling through stormy patches of dark clouds,” team leader Sylvestre Lacour, a researcher at the Observatoire de Paris and the Max Planck Institute for Extraterrestrial Physics, said in a statement. “Convection moves around the clouds of silicate and iron particles, which disaggregate and rain down into the interior. This paints a picture of a dynamic atmosphere of a giant exoplanet at birth, undergoing complex physical and chemical processes.”
To reach this level of detail, the team used the GRAVITY instrument, which turns the observatories that make up ESO’s Very Large Telescope into a single giant telescope with 25 times more resolving power. And this led to some surprising discoveries about the planet.
“Our analysis showed that HR8799e has an atmosphere containing far more carbon monoxide than methane – something not expected from equilibrium chemistry,” explained Lacour. “We can best explain this surprising result with high vertical winds within the atmosphere preventing the carbon monoxide from reacting with hydrogen to form methane.”
While exoplanet observations are extremely important, this is just one of the things that the technique has been used for. GRAVITY has already been employed to study the supermassive black hole at the center of the Milky Way, witnessing material swirling around it at 30 percent of the speed of light.