Skip to main content

Heaviest element ever discovered in exoplanet atmospheres is a puzzle

When it comes to finding habitable exoplanets, the next big challenge is not just spotting exoplanets or looking at their orbits, but getting a better understanding of what conditions there might be like by analyzing their atmospheres. New tools like the James Webb Space Telescope will allow us to peer into the atmospheres of exoplanets and see what they are composed of, which can affect the planet’s surface temperature, pressure, and weather systems.

Now, astronomers using the European Southern Observatory’s Very Large Telescope (ESO’s VLT), a ground-based telescope located in Chile, have discovered the heaviest element ever in an exoplanet atmosphere. Looking at two ultra-hot gas giants called WASP-76 b and WASP-121 b, the researchers identified the element barium in their atmospheres.

Artist’s impression of an ultra-hot exoplanet as it is about to transit in front of its host star.
This artist’s impression shows an ultra-hot exoplanet, a planet beyond our Solar System, as it is about to transit in front of its host star. Using the ESPRESSO instrument of ESO’s Very Large Telescope, astronomers have found the heaviest element yet in an exoplanet’s atmosphere, barium, in the two ultra-hot Jupiters WASP-76 b and WASP-121 b. ESO/M. Kornmesser

These two planets orbit extremely close to their respective stars and thus have extremely high surface temperatures which can go over 1,000 degrees Celsius. On one of the planets, WASP-76 b, it gets so got that iron falls from the sky as rain. But the researchers were surprised to find barium high in the atmospheres of these planets because it is so heavy.

Recommended Videos

“The puzzling and counterintuitive part is: why is there such a heavy element in the upper layers of the atmosphere of these planets?” said lead author Tomás Azevedo Silva of the Instituto de Astrofísica e Ciências do Espaço (IA) in Portugal, in a statement.

“Given the high gravity of the planets, we would expect heavy elements like barium to quickly fall into the lower layers of the atmosphere,” said co-author Olivier Demangeon.

The researchers still aren’t sure what is causing this very heavy element to appear in the exoplanet atmospheres, but the fact it has been identified in not one but two different hot Jupiter atmospheres is interesting. Further research will be needed to discover where this barium came from and how it stays so high in the atmosphere.

The research is published in the journal Astronomy & Astrophysics.

Georgina Torbet
Georgina is the Digital Trends space writer, covering human space exploration, planetary science, and cosmology. She…
This extreme exoplanet has a highly unusual orbit
This artist’s impression shows a Jupiter-like exoplanet that is on its way to becoming a hot Jupiter — a large, Jupiter-like exoplanet that orbits very close to its star. Using the WIYN 3.5-meter telescope at the U.S. National Science Foundation Kitt Peak National Observatory, a Program of NSF NOIRLab, a team of astronomers found that this exoplanet, named TIC 241249530 b, follows an extremely elliptical orbit in the direction opposite to the rotation of its host star.

This artist’s impression shows a Jupiter-like exoplanet that is on its way to becoming a hot Jupiter — a large, Jupiter-like exoplanet that orbits very close to its star. NOIRLab/NSF/AURA/J. da Silva (Spaceengine)

Exoplanets come in all sorts of shapes and sizes, and can be weird in all sorts of ways. There are football shaped exoplanets and exoplanets where it rains gemstones; ones with the density of cotton candy and ones with one lava hemisphere. But new research has uncovered an exoplanet called TIC 241249530 b which is unusual in a different sort of way, as it has one of the most extreme orbits discovered to date.

Read more
Is this the most beautiful rocket launch ever?
A Falcon 9 rocket launches from California.

SpaceX chief Elon Musk has shared a video of an astonishingly beautiful Falcon 9 launch.

It shows the start of the NROL-186 mission, which took place last week and deployed next-generation spy satellites for the National Reconnaissance Office (NRO).

Read more
James Webb discovers the most distant galaxy ever observed
JADES (NIRCam Image with Pullout). The NIRCam data was used to determine which galaxies to study further with spectroscopic observations. One such galaxy, JADES-GS-z14-0 (shown in the pullout), was determined to be at a redshift of 14.32 (+0.08/-0.20), making it the current record-holder for the most distant known galaxy. This corresponds to a time less than 300 million years after the big bang.

JADES (NIRCam Image with Pullout). The NIRCam data was used to determine which galaxies to study further with spectroscopic observations. One such galaxy, JADES-GS-z14-0 (shown in the pullout), was determined to be at a redshift of 14.32 (+0.08/-0.20), making it the current record-holder for the most distant known galaxy. This corresponds to a time less than 300 million years after the big bang. Credit: NASA, ESA, CSA, STScI, B. Robertson (UC Santa Cruz), B. Johnson (CfA), S. Tacchella (Cambridge), P. Cargile (CfA). NASA

Researchers using the James Webb Space Telescope have discovered the most distant known galaxy to date, one that is so far away that it existed just a few hundred million years after the Big Bang. Since Webb began its science operations in 2022, astronomers have used it to look for very distant, very ancient galaxies and have been surprised by what they found. Not only have they found many of these distant galaxies, but the galaxies are also brighter and more massive than they expected -- suggesting that galaxies evolved into large sizes faster than anyone imagined.

Read more