An exciting discovery in the field of space exploration has captured the attention of astronomers. The exoplanet LHS 1140 blocated just 40 light-years from Earth in the constellation of Cetus, could be the Super-Earth most similar to our planet never identified so far.
Initially classified as Mini-Neptunefollowing its discovery in 2023 by NASA’s James Webb Space Telescope, new analyses suggest that LHS 1140 b is actually a super-Earth. This type of planet is more massive than Earth but retains terrestrial characteristics.
LHS 1140 b may be the exoplanet with the best chance of hosting water on its surface.
A team of researchers led by the astronomer Charles Cadieux of the University of Montreal conducted an in-depth study pubblicato su The Astrophysical Journal Letters.
The results indicate that LHS 1140 b could be theexoplanet with the best chance of hosting liquid water on its surfacemaking it potentially habitable.
The proximity of LHS 1140 b to its red dwarf star suggests that It could be a huge ice planet or a mostly frozen body with an ocean in the region closest to the star. This configuration would give it the appearance of a “cosmic eye”.
The study revealed “tantalizing evidence for a nitrogen-dominated atmosphere on a super-Earth in the habitable zone.” This finding is particularly significant for the search for potentially habitable worlds outside our solar system.
The researchers used the NIRISS (Near-Infrared Imager and Slitless Spectrograph) instrument of the Webb telescope to observe two transits of LHS 1140 b in December 2023. Using transit spectroscopy, they analyzed the light from the host star passing through the planet’s atmosphere.
To test the initial hypothesis of a mini-Neptune, the team created a 3D global climate model (GCM). By comparing several GCMs with the observed light spectrum, they found that the mini-Neptune model did not match the NIRISS observations.
The collected data instead support the idea of a super-Earth with asecondary atmosphere rich in nitrogen or CO2, similar to that of Earth. The lower density than expected for a rocky world suggests that it may be an “ocean planet” with a mass composed of 10-20% water.
Despite these promising findings, further observations are needed to confirm the nature of LHS 1140 bCadieux’s team plans to compare the NIRISS data with those of other super-Earths collected by Webb’s NIRSpec instrument.
At least are expected three transit observations of the planet with Webb’s MIRI (Mid-Infrared) instrument to exclude interference from stellar radiation in observations of the planet itself.
Scientists warn that “given the limited visibility of LHS 1140 b, it may be necessary several years of observations to detect its potential secondary atmosphere.”
The research on LHS 1140 b represents a significant step in our understanding of exoplanets and in the search for potentially habitable worlds. While we await further data, the possibility of an “icy Earth” just 40 light-years away continues to fascinate the scientific community and the public.
Source: www.tomshw.it
