Coolest lava world yet with signs of an atmosphere offers clues to early Earth

A newly cataloged planet, HD 3167 b, has been found to have an atmosphere despite its extreme heat, offering new insights into planetary formation and atmospheric retention. This super-Earth, located 154 light-years away in the constellation Pisces, orbits its star in just one Earth day and is one of the hottest known exoplanets. The discovery challenges previous assumptions about the difficulty of forming atmospheres on rocky planets, as it shows that some ultra-hot lava worlds can retain atmospheres. The study, led by University of Chicago scientist Brandon Park Coy, used the James Webb Space Telescope to detect mid-infrared light, which helps estimate a planet's temperature and potential atmosphere.

The study found that HD 3167 b's dayside is cooler than expected, suggesting it has an atmosphere. This is significant because it helps understand the temperature transition between planets with and without atmospheres. The planet is the coolest lava world found with an atmosphere, and it is part of a program led by Megan Weiner Mansfield that aims to study 10 ultra-hot lava worlds to determine if there's a critical temperature for atmosphere formation. The research indicates that these planets may have silicate-rich atmospheres, with possible traces of heavier gases like carbon dioxide or water. The findings raise questions about the conditions under which silicate atmospheres form and how they affect planetary temperatures.

The discovery is important because it provides a window into early Earth's conditions. It suggests that early in the solar system's history, terrestrial planets might have been extremely hot, similar to HD 3167 b. The study highlights the complexity of planetary formation and the role of atmospheres in shaping planetary surfaces. The result supports the idea that planets with atmospheres can form even in the most extreme conditions, offering clues about the origins of Earth's early atmosphere.

AI-generated summary of the original article — see the source for the full story.