NASA's Webb Telescope Could Find Life On Habitable Earth-Like Exoplanet TRAPPIIST-1e
Fresh data from NASA's James Webb Space Telescope (JWST) has provided new clues about the nature of the exoplanet TRAPPIST-1 e, a rocky world located just 40 light-years from Earth. Even if researchers have yet to definitively confirm it, JWST's initial findings have hinted at an exciting possibility: a nitrogen-rich atmosphere, which could in turn increase the odds of the planet being habitable.
TRAPPIST-1 e is one of seven Earth-sized planets orbiting a small, cool red dwarf star ("e" denotes it as the fifth planet in the system). Of these, it's been considered a prime target in the search for life because it sits squarely in the star’s habitable zone—the sweet spot where temperatures can allow for liquid water to exist on the planet’s surface. However, the potential for life hinges entirely on whether the planet can maintain a stable atmosphere. In TRAPPIST-1 e's case, the host star (TRAPPIST-1) is known to emit powerful flares that could easily strip a planet of its gaseous envelope.
TRAPPIST-1 e is one of seven Earth-sized planets orbiting a small, cool red dwarf star ("e" denotes it as the fifth planet in the system). Of these, it's been considered a prime target in the search for life because it sits squarely in the star’s habitable zone—the sweet spot where temperatures can allow for liquid water to exist on the planet’s surface. However, the potential for life hinges entirely on whether the planet can maintain a stable atmosphere. In TRAPPIST-1 e's case, the host star (TRAPPIST-1) is known to emit powerful flares that could easily strip a planet of its gaseous envelope.
To find the answer, astronomers used JWST’s Near-Infrared Spectrograph (NIRSpec) instrument to observe the planet as it transited its star. The idea was to analyze starlight that filtered through TRAPPIST-1 e’s atmosphere, if one exists, to hopefully detect any telltale signs of various gases. Interference from the star’s immense activity, which can mimic or obscure faint signals from the planet, made it extra challenging for the team.
Following a year of analysis, the research team from the University of St Andrews and other institutions published their initial findings in the Astrophysical Journal Letters. The report indicates that TRAPPIST-1 e is unlikely to have a thick, hydrogen-dominated or a carbon dioxide atmospheres like those on Venus and Mars, respectively. This narrows the possibilities to two main scenarios: either the planet is a barren, airless rock, or it possesses a so-called secondary atmosphere composed of heavier gases.
The most exciting scenario to emerge is a nitrogen-dominated atmosphere with trace amounts of methane. Such an environment would be a crucial step toward creating conditions for a stable climate and liquid water, potentially supporting a global ocean or an ice-covered surface. While the initial data cannot definitively confirm the existence of an atmosphere, it does provide a tentative preference for this model over the airless one.
Subsequently, the team is scheduled to conduct 15 additional transit observations of TRAPPIST-1 e to gather more data and perhaps confirm or rule out the presence of an atmosphere.
