Research into the TRAPPIST-1 star system reveals that the fourth planet, known as TRAPPIST-1e, may have lost its original atmosphere and faces uncertainty regarding the possibility of rebuilding one. Scientists utilized the James Webb Space Telescope to gather these early findings, which suggest that the planet, located approximately 40 light-years from Earth, is not likely to have retained a hydrogen-helium atmosphere due to intense stellar flares from its host star, a red dwarf.
The TRAPPIST-1 system, discovered by NASA around eight years ago, consists of seven rocky exoplanets. Among these, TRAPPIST-1e has emerged as a strong candidate for supporting life because it resides within the so-called habitable zone, where temperatures may allow for liquid water if an atmosphere is present. According to Nikole Lewis, an astronomy professor at Cornell University, “TRAPPIST-1 is a very different star from our sun, and so the planetary system around it is also very different.”
Initial Findings and Future Research
The two scientific papers detailing these findings were published in the Astrophysical Journal Letters. These results follow shortly after findings regarding TRAPPIST-1d, another planet in the same system, which also indicated a bleak outlook for potential habitability.
Scientists are employing a technique known as transmission spectroscopy to investigate the atmospheres of these planets. This method involves analyzing starlight that filters through a planet’s atmosphere as it transits in front of its star. Each gas absorbs specific wavelengths of light, allowing researchers to identify the chemical composition. Yet, this approach can produce ambiguous results due to factors like sunspots and other stellar activities.
The research team, having conducted only four of a planned nineteen observations, aims to share their methodology with the broader scientific community to foster collaboration and enhance the interpretation of their findings. As they continue their work, they plan to compare signals from TRAPPIST-1e with those from TRAPPIST-1b, which appears to be a bare, airless rock. By synchronizing their observations of both planets, the team can distinguish between signals originating from the star and those that are characteristic of TRAPPIST-1e’s atmosphere.
Exploring the Possibility of New Atmospheres
While current data indicates that TRAPPIST-1e likely lost its original atmosphere, the potential for it to develop a new one remains. Just as Earth underwent this process billions of years ago, researchers are curious whether TRAPPIST-1e could have experienced a similar transformation. The researchers have devised a strategy to investigate this by timing their observations to capture both planets crossing the star simultaneously.
A major focus for scientists using the James Webb Space Telescope is whether red dwarfs can host planets with atmospheres. To address this question, Webb scientists have initiated a comprehensive survey of rocky planets, recently reported by Mashable. This new survey will utilize the “secondary eclipse” method, which mitigates some complications caused by stellar activity compared to transmission spectroscopy.
According to Ana Glidden, a lead author from MIT, “We are really still in the early stages of learning what kind of amazing science we can do with Webb. We’re in a new age of exploration that’s very exciting to be a part of.” As the research progresses, the findings from the TRAPPIST-1 system could significantly enhance our understanding of exoplanets and their potential for harboring life.
