The rocky exoplanet called LHS 1140b, located approximately 48 light years away from Earth, has again entered the agenda of the scientific world in the search for life. Astronomers have reached one of the strongest evidence yet that LHS 1140b may have an atmosphere, by detecting traces of helium escaping into space from the planet’s surroundings.
According to the research published in the journal Science, helium signals escaping from the planet’s upper atmosphere into space were detected during near-infrared observations. Since an atmosphere must first surround the planet for a gas to escape into space, this discovery strengthened the possibility that LHS 1140b carries an atmosphere.
IT IS LOCATED IN THE LIVIBLE ZONE
Another reason why LHS 1140b attracts attention is that it is located in the “habitable zone” of its star. This region represents the distance where liquid water could exist on the planet’s surface if suitable conditions occur. However, scientists underline that being in the habitable zone does not necessarily mean that there is water or life.
HELIUM WAS OBSERVED FOR ONLY A YEAR
As part of the research, scientists analyzed the filtering of starlight through the atmosphere as it passed in front of the star LHS 1140b using spectroscopy. Clues about the composition of the atmosphere were obtained thanks to the absorption of certain wavelengths of light by gases.
During the examinations, traces of helium absorption were detected in the near infrared spectrum. However, the remarkable point was that this signal was seen only in observations made in 2024. The same trace was not found in the observations in 2025. The researchers stated that this may indicate that gas escape from the atmosphere may vary over time.
The observations were made with the near-infrared spectrograph of the Magellan Clay Telescope at Las Campanas Observatory in Chile. A similar helium signal was not detected on the other planet called LHS 1140c in the same star system.
THE UPPER ATMOSPHERE MAY BE RICH IN HELIUM
Researchers stated that the data obtained suggests that the upper atmosphere of LHS 1140b may be rich in helium and poor in hydrogen. It was evaluated that heavier volatile gases may be held in the lower layers of the atmosphere.
Since helium is a light element, it accumulates in the upper atmosphere and escapes into space more easily. Therefore, the detection of escaping helium is considered indirect evidence for the existence of lower atmospheric layers that are difficult to observe directly.
Previous models developed by Collin Cherubim, the lead author of the research, and his team also predicted that helium could escape from the atmosphere in LHS 1140b. New observations have revealed data supporting this prediction.
MORE OBSERVATIONS ARE NEEDED FOR THE LIKELIHOOD OF SURVIVAL
LHS 1140b orbiting a low-mass red dwarf star; It is seen as one of the most important exoplanets to be examined in the search for life in the future, thanks to its rocky structure, location in the habitable zone and findings that it may contain an atmosphere.
Atmospheres can regulate planets’ climate, protect their surfaces from harmful stellar radiation, and prevent liquid water from escaping into space. However, the current study does not reveal that there is water in LHS 1140b or that the atmosphere has a structure that supports life.
Scientists state that more sensitive observations are needed to understand whether there is nitrogen, water vapor or other molecules that could be associated with life in the planet’s lower atmosphere.
IT IS TOO EARLY TO SAY “SECOND WORLD”
The researchers particularly emphasize that the results obtained do not show that there is life in LHS 1140b. Additionally, since the helium signal was detected only in a single observation period, the finding needs to be confirmed by independent studies.
Scientists state that they do not yet know the exact structure of the planet’s lower atmosphere and whether there is liquid water on its surface, and that the definition of LHS 1140b as the “twin of the Earth” or a planet hosting life is not supported by current scientific data.
