homehome Home chatchat Notifications


JWST finds a planet with an atmosphere like no other

The JWST is becoming an exoplanet researcher's dream.

Jordan Strickler
November 23, 2022 @ 10:27 pm

share Share

The James Webb Space Telescope just won’t stop finding new stuff. This time, it was a detailed chemical and molecular picture of the atmosphere of a faraway world that is unlike anything we’ve seen so far.

With the JWST, new observations of WASP-39b have given us a better idea of what it’s atmosphere looks like. (Credit: Melissa Weiss/Center for Astrophysics | Harvard & Smithsonian)

The telescope’s array of highly sensitive instruments was trained on WASP-39 b‘s atmosphere, a planet with roughly the same mass as Saturn but much hotter (it is referred to as a “hot Saturn”). The planet, which lies some 700 light-years away, has an atmosphere at a toasty 1,600 degrees Fahrenheit (871 degrees Celsius). While the JWST, along with Hubble and Spitzer, have previously revealed isolated components of this planet’s atmosphere, the new readings provide a comprehensive menu of atoms, molecules, and even indications of active chemistry and fragmented clouds.

“The clarity of the signals from a number of different molecules in the data is remarkable,” says  Mercedes López-Morales, an astronomer at the Center for Astrophysics | Harvard & Smithsonian and one of the scientists who contributed to the new results. “We had predicted that we were going to see many of those signals, but still, when I first saw the data, I was in awe.”

The new findings continue to make JWST a great go-to source for conducting a variety of investigations on exoplanets, as this study indicates that figuring out various bits of information about planets’ atmospheres will be possible. This includes investigating the atmospheres of smaller, rocky planets in the TRAPPIST-1 system.

The telescope that keeps on giving

The discoveries are described in five recently submitted scientific papers, available on the preprint website arXiv. One of the most groundbreaking discoveries is the first detection of sulfur dioxide in an exoplanet’s atmosphere. This molecule is produced by chemical reactions triggered by high-energy light from the planet’s parent star. A similar process creates the protective ozone layer in the upper atmosphere on Earth.

“The surprising detection of sulfur dioxide finally confirms that photochemistry shapes the climate of ‘hot Saturns,’” says Diana Powell, a NASA Hubble fellow, astronomer at the Center for Astrophysics and core member of the team that made the sulfur dioxide discovery. “Earth’s climate is also shaped by photochemistry, so our planet has more in common with ‘hot Saturns’ than we previously knew!”

Sodium, potassium, and water vapor are some of the other atmospheric components that JWST detected. These observations have been confirmed by ground- and space-based telescopes and JWST has also discovered new water features at longer wavelengths.

The JWST also observed carbon dioxide with greater clarity, with the spacecraft providing twice as much data as has been previously reported. While CO2 was found, neither methane nor hydrogen sulfide showed up in the data. If they are actually present, these molecules occur at very low levels. However, if they are in WASP 39 b’s atmosphere, it would be a significant finding for scientists making inventories of exoplanet chemistry in order to better understand the formation and development of these distant worlds.

To find these chemicals, JWST tracked WASP-39 b as it passed in front of its host star, allowing some of the star’s light to pass through the planet’s atmosphere and allowing observers to detect light from the object. Astronomers can identify the molecules by looking at the colors that are and aren’t present because different kinds of chemicals in the atmosphere absorb different colors of the starlight spectrum.

Eight times closer to its star than Mercury is to our Sun, WASP-39 b serves as an excellent testing ground for the effects of radiation from host stars on exoplanets. A deeper comprehension of the star-planet relationship should result in a better understanding of how these processes produce the variety of planets seen in the galaxy.

“We observed the exoplanet with multiple instruments that, together, provide a broad swath of the infrared spectrum and a panoply of chemical fingerprints inaccessible until JWST,” said Natalie Batalha, an astronomer at the University of California, Santa Cruz, who contributed to and helped coordinate the new research. “Data like these are a game changer.”

share Share

Researchers Turn 'Moon Dust' Into Solar Panels That Could Power Future Space Cities

"Moonglass" could one day keep the lights on.

Three Secret Russian Satellites Moved Strangely in Orbit and Then Dropped an Unidentified Object

We may be witnessing a glimpse into space warfare.

This strange rock on Mars is forcing us to rethink the Red Planet’s history

A strange rock covered in tiny spheres may hold secrets to Mars’ watery — or fiery — past.

We Should Start Worrying About Space Piracy. Here's Why This Could be A Big Deal

“We are arguing that it’s already started," say experts.

The most successful space telescope you never heard of just shut down

An astronomer says goodbye to Gaia, the satellite that mapped the galaxy.

Astronauts are about to grow mushrooms in space for the first time. It could help us live on Mars

Mushrooms could become the ultimate food for living in colonies on the moon and Mars.

Dark Energy Might Be Fading and That Could Flip the Universe’s Fate

Astronomers discover hints that the force driving cosmic expansion could be fading

Curiosity Just Found Mars' Biggest Organic Molecules Yet. It Could Be A Sign of Life

The discovery of long-chain organic compounds in a 3.7-billion-year-old rock raises new questions about the Red Planet’s past habitability.

Astronomers Just Found Oxygen in a Galaxy Born Only 300 Million Years After the Big Bang

The JWST once again proves it might have been worth the money.

New NASA satellite mapped the oceans like never before

We know more about our Moon and Mars than the bottom of our oceans.