1. Home
  2. Space
  3. News

Peering into the atmosphere of an ultra-hot exoplanet

By

Of the over 4,000 exoplanets discovered so far, one of the strangest has to be WASP-189b. This ultra-hot Jupiter orbits so close to its star that its surface temperature could be up to 3,200 degrees Celsius, which is hot enough for iron to evaporate. Now, astronomers using the CHEOPS space telescope have investigated WASP-189b’s atmosphere and found that it’s just as odd as the planet beneath.

It’s not easy to investigate the atmosphere of an exoplanet, but in this case, the researchers were able to look at the light coming from the extremely hot nearby star. “We measured the light coming from the planet’s host star and passing through the planet’s atmosphere,” lead author of the study, Bibiana Prinoth, explained in a statement. “The gases in its atmosphere absorb some of the starlight, similar to Ozone absorbing some of the sunlight in Earth’s atmosphere, and thereby leave their characteristic ‘fingerprint’. With the help of [the HARPS spectrograph], we were able to identify the corresponding substances.”

Artist’s impression of WASP-189b, an exoplanet orbiting the star HD 133112 which is one of the hottest stars known to have a planetary system. Bibiana Prinoth

The team found indications of gases including iron, chromium, vanadium, magnesium, and manganese. One substance that was indicated and is particularly intriguing is titanium oxide, which could act similarly to the way ozone acts in Earth’s atmosphere, absorbing ultraviolet radiation. There were also differences between what the team predicted and what they actually found, which suggests that the exoplanet atmosphere could be complex and affected by strong winds, having different layers which are composed of different gases.

Recommended Videos

While Earth’s atmosphere has layers, the assumption when studying exoplanet atmospheres has often been that they would be more simple. But this research shows that isn’t necessarily the case. “In the past, astronomers often assumed that the atmospheres of exoplanets exist as a uniform layer and try to understand it as such,” said co-author Jens Hoeijmakers. “But our results demonstrate that even the atmospheres of intensely irradiated giant gas planets have complex three-dimensional structures.”

“We are convinced that to be able to fully understand these and other types of planets – including ones more similar to Earth, we need to appreciate the three-dimensional nature of their atmospheres,” agreed co-author Kevin Heng. “This requires innovations in data analysis techniques, computer modeling and fundamental atmospheric theory.”

The research is published in the journal Nature Astronomy.

Editors' Recommendations

Topics
Georgina Torbet
Space Writer
Georgina is the Digital Trends space writer, covering human space exploration, planetary science, and cosmology. She…
Small exoplanet could be hot and steamy according to Hubble

One of the big topics in exoplanet research right now is not just finding exoplanets but also looking at their atmospheres. Tools like the James Webb Space Telescope are designed to allow researchers to look at the light coming from distant stars and see how it is filtered as it passes by exoplanets, allowing them to learn about the composition of their atmospheres. But scientists are also using older telescopes like the Hubble Space Telescope for similar research -- and Hubble recently identified water vapor in an exoplanet atmosphere.

“This would be the first time that we can directly show through an atmospheric detection that these planets with water-rich atmospheres can actually exist around other stars,” said researcher Björn Benneke of the Université de Montréal in a statement. “This is an important step toward determining the prevalence and diversity of atmospheres on rocky planets."

Read more
Astronomers discover extremely hot exoplanet with ‘lava hemisphere’

Astronomers have discovered an Earth-sized exoplanet with an unusually extreme climate where one half of the planet is thought to be covered in lava. The planet HD 63433 d is tidally locked, meaning one side of it always faces its star while the other half always faces out into space, creating a huge difference in temperatures between the planet's two faces.

Like Kepler-10 b, illustrated above, the exoplanet HD 63433 d is a small, rocky planet in a tight orbit of its star. HD 63433 d is the smallest confirmed exoplanet younger than 500 million years old.  NASA/Ames/JPL-Caltech/T. Pyle

Read more
See the weather patterns on a wild, super hot exoplanet

When it comes to understanding exoplanets, or planets outside our solar system, the big challenge is in not only finding these planets, but also understanding what they are like. And one of the biggest factors that scientists are interested in is whether an exoplanet has an atmosphere and, if so, what it is composed of. But, just like with weather here on Earth, exoplanet atmospheres aren't static. So the Hubble Space Telescope was recently used for an intriguing observation -- comparing data from an exoplanet atmosphere that had previously been observed, to see how it changed over time.

Hubble looked at planet WASP-121 b, an extreme planet that is so close to its star that a year there lasts just 30 hours. Its surface temperatures are over 3,000 Kelvins, or 5,000 degrees Fahrenheit, which researchers predict would lead to some wild weather phenomena. As it is such an extreme planet, WASP-121 b is well-known and has been observed by Hubble several times over the years, beginning in 2016.

Read more