Study Finds No Signs of Life-Supporting Atmosphere on Trappist-1 d

Astronomers from the University of Chicago, using the James Webb Space Telescope, have found that Trappist-1 d—a rocky exoplanet located approximately 40 light-years from Earth—shows no signs of an atmosphere capable of supporting life. The findings were published on Wednesday, August 14, 2025, in The Astrophysical Journal, and mark a significant development in the ongoing search for extraterrestrial life.

Trappist-1 d is the third of seven planets orbiting the red dwarf star Trappist-1, a small, cool star slightly larger than Jupiter. The system first gained attention in 2017 when scientists announced that all seven planets were Earth-sized and potentially habitable. Its proximity and compact orbits make it ideal for transmission spectroscopy—a method that analyzes starlight as it passes through a planet’s atmosphere to detect chemical signatures.

Researchers had hoped Trappist-1 d might possess Earth-like conditions, but recent data suggest otherwise. Lead researcher Caroline Piaulet-Ghorayeb explained that the starlight reaching the Webb telescope showed no signs of filtering through molecules essential to life, such as water or carbon dioxide. “Maybe that tells us that it’s going to be harder than we thought to find atmospheres on these rocky planets,” she said.

While the study doesn’t entirely rule out the presence of an atmosphere, it suggests that red dwarfs like Trappist-1 may be too volatile to support life. These stars often emit intense radiation and flares, which could strip away planetary atmospheres over time.

The Trappist-1 system was once considered one of the most promising locations for finding life outside Earth. But with no signs of life-supporting atmospheres on the inner planets—including Trappist-1 d—scientists may need to rethink their strategies and shift focus to planets orbiting brighter, more stable stars like our sun.

Jacob Bean, an astronomer at the University of Chicago who advises Dr. Piaulet-Ghorayeb, said future discoveries may require new telescopes and different targets. “We still have this burning question: Can life develop elsewhere?” he said. “If we go look, sometimes we come up disappointed. But if we hadn’t looked, we wouldn’t know. And it’s always better to know.”

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