Webb does the ‘impossible’ – The Space Telescope captured the first look inside an exoplanet

The James Webb Space Telescope the data reveal that WASP-107 b has significantly less methane than expected and a surprisingly large core, providing key insights into its atmospheric chemistry and internal dynamics.

The cotton candy-like planet WASP-107 b harbors a surprisingly low amount of methane and a super-massive core.

The revelations, based on data obtained by the James Webb Space Telescope, mark the first measurements of an exoplanetcore matter and will likely support future studies of planetary atmospheres and interiors, a key aspect in the search for habitable worlds outside our solar system.

“Seeing the interior of a planet hundreds of light-years away sounds almost impossible, but when you know the mass, radius, composition of the atmosphere, and the heat of its interior, you have all the pieces you need to get an idea. what’s inside and how heavy that core is,” said lead author David Sing, Bloomberg Distinguished Professor of Earth and Planetary Sciences at Johns Hopkins University. “This is now something we can do for a lot of different gas planets in different systems.”

Recently published in NatureThe research shows that the planet has a thousand times less methane than expected and a core 12 times more massive than Earth’s.

Planetary composition and potential for habitability

A giant planet enveloped in a scorching cotton-fluffy atmosphere, WASP-107 b orbits a star about 200 light-years away. He is bloated because of his build: a Jupiter-a large world with only one-tenth the mass of this planet.

Although it has methane – the building block of life on Earth – the planet is not considered habitable due to its proximity to its parent star and lack of a solid surface. But it could contain important clues about the late phase of planetary evolution.

Methane Mysteries and Chemical Dynamics

In a separate study published in Natureother scientists also spotted methane using the Webb telescope, providing similar insights into the planet’s size and density.

“We want to look at planets more like gas giants in our own solar system that have a lot of methane in their atmospheres,” Sing said. “This is where the WASP-107b story got really interesting because we didn’t know why the methane levels were so low.”

The new measurements of methane suggest that the molecule is being transformed into other compounds as it flows upward from the planet’s interior and interacts with a mix of other chemicals and starlight in the upper atmosphere. The team also measured sulfur dioxide, water vapor, carbon dioxide and carbon monoxide – and found that WASP-107b contains more heavy elements than Uranium and Neptune.

Observational study and future research

Profiling the planet’s chemistry is beginning to reveal key pieces of the puzzle of how planetary atmospheres behave under extreme conditions, Sing said. His team will make similar observations over the next year on another 25 planets using the Webb telescope.

“We’ve never been able to study this mixing process in exoplanet atmospheres in detail, so it will go a long way toward understanding how these dynamic chemical reactions work,” Sing said. “It’s something we definitely need as we start looking at rocky planets and biomarkers.”

Internal heat sources and atmospheric influences

Scientists have speculated that the planet’s over-dense radius is the result of a heat source inside, said Zafar Rustamkulov, a Johns Hopkins doctoral student in planetary science who co-led the research. By combining atmospheric and internal physics models with Webb’s WASP-107b data, the team explained how the planet’s thermodynamics affect its observable atmosphere.

“The planet has a hot core, and this source of heat changes the chemistry of the gases more deeply, but also drives this strong, convective mixing bubbling up from the interior,” Rustamkulov said. “We think this heat causes the chemistry of the gases to change, specifically destroying methane and creating increased amounts of carbon dioxide and carbon monoxide.”

Ongoing investigations and future experiments

The new findings also represent the clearest connection scientists have been able to make between the interior of an exoplanet and the top of its atmosphere, Rustamkulov said. Last year, the Webb telescope spotted sulfur dioxide about 700 light-years away on another exoplanet called WASP-39, providing the first evidence of an atmospheric compound created by reactions driven by starlight.

The Johns Hopkins team is now focusing on what might be keeping the core hot, and expects that forces similar to those that cause tides in Earth’s oceans may be at play. They plan to test whether the planet is being stretched and pulled by its star and how the high heat of the core might explain this.

Reference:

“Neptune’s Warm Methane Reveals Core Mass and Vigorous Atmospheric Mixing” by David K. Sing, Zafar Rustamkulov, Daniel P. Thorngren, Joanna K. Barstow, Pascal Tremblin, Catarina Alves de Oliveira, Tracy L. Beck, Stephan M. Birkmann, Ryan C. Challener, Nicolas Crouzet, Néstor Espinoza, Pierre Ferruit, Giovanna Giardino, Amélie Gressier, Elspeth KH Lee, Nikole K. Lewis, Roberto Maiolino, Elena Manjavacas, Bernard J. Rauscher, Marco Sirianni, and Jeff A. Valenti, May 20 2024, Nature.
DOI: 10.1038/s41586-024-07395-z

“High internal heat flow and a large core in a warm Neptunian exoplanet” by Luis Welbanks, Taylor J. Bell, Thomas G. Beatty, Michael R. Line, Kazumasa Ohno, Jonathan J. Fortney, Everett Schlawin, Thomas P. Green, Emily Rauscher , Peter McGill, Matthew Murphy, Vivien Parmentier, Yao Tang, Isaac Edelman, Sagnick Mukherjee, Lindsey S. Wiser, Pierre-Olivier Lagage, Achrène Dyrek, and Kenneth E. Arnold, 20 May 2024, Nature.
DOI: 10.1038/s41586-024-07514-w

Other authors of the study are Daniel P. Thorngren and Elena Manjavacas of Johns Hopkins University; Joanna K. Barstow of the Open University; Pascal Tremblin of the Université Paris-Saclay; Catarina Alves de Oliveira, Stephan M. Birkmann and Pierre Ferruit European Space Agency; Tracy L. Beck, Néstor Espinoza, Amélie Gressier, Marco Sirianni, and Jeff A. Valenti of the Space Telescope Science Institute; Ryan C. Challener of Cornell University; Nicolas Crouzet, Giovanna Giardino and Nikole K. Lewis of Leiden University; Elspeth KH Lee; Roberto Maiolino of the University of Cambridge; and Bernard J. Rauscher of NASA Goddard Space Flight Center.

This research is based on data obtained from the Space Telescope Science Institute, operated by the Association of Universities for Research in Astronomy Inc., under NASA contract NAS 5-03127.