Tucson Standard

NASA's James Webb Space Telescope has provided a team of astronomers, including University of Arizona researcher Everett Schlawin, with new insights into the composition of a common type of exoplanet. These findings have revealed what Schlawin describes as a "new class of planet."

Within our solar system, planets like Mercury, Jupiter, and Earth are familiar. However, over 5,000 exoplanets around other stars differ significantly from those in our solar system. Among them is GJ 1214 b, a sub-Neptune located 48 light-years away. This planet represents an entire category unlike any found here.

Schlawin and Kazumasa Ohno from the National Astronomical Observatory of Japan led an international team using the James Webb Space Telescope to study GJ 1214 b's atmosphere for the first time. Their research is published in The Astrophysical Journal Letters.

Discovered in 2009 and formally named Enaiposha by the International Astronomical Union in 2023, this planet was initially thought to be oceanic. However, previous atmospheric studies were inconclusive. Matthew Murphy from the University of Arizona noted it had been a long-standing puzzle.

Using JWST's Near-Infrared Spectrograph (NIRSpec), researchers applied transmission spectroscopy to detect gases in GJ 1214 b's atmosphere. Contrary to expectations of a water world, they found carbon dioxide dominance.

"The detected CO2 signal from the first study is tiny," said Ohno. He used theoretical models to determine that GJ 1214 b's atmosphere is likely carbon-dominated.

Schlawin compared detecting this small atmospheric signature to finding a changed sentence in two copies of Leo Tolstoy's "War and Peace."

The research underscores JWST's capabilities and highlights future study needs for understanding these mysterious exoplanets. As Murphy put it, "It's amazing what you can do when you have a team from all over the globe."

These findings may lead to further exploration of smaller rocky planets that could address fundamental questions about life beyond Earth.