A WATER ‘super-Earth’ about 50 light-years away may have the conditions to host life.
LHS 1140 b is an exoplanet orbiting a red dwarf star in the constellation Cetus. It falls in the star’s habitable zone, or the region with temperatures that support liquid water.
Now, a team of scientists has determined that the planet may harbor an Earth-like atmosphere and ocean.
An article published this week in The letters from the astrophysical journal identified LHS 1140 b as one of the most promising candidates capable of sustaining life.
“Of all the currently known temperate exoplanets, LHS 1140 b may well be our best bet to one day indirectly confirm liquid water on the surface of an alien world beyond our solar system,” said the lead author. Carlos Cadieux said in a statement.
“This would be an important milestone in the search for potentially habitable exoplanets.”
The team, led by researchers at the University of Montreal, examined data collected by NASA’s James Webb Space Telescope.
It added to previous data from other telescopes, including Spitzer and Hubble.
In their analysis, scientists ruled out the possibility that LHS 1140 was a mini-Neptune with a hydrogen-rich atmosphere.
Instead, they found evidence that it is, in fact, a super-Earth – a rocky or watery planet with a radius approximately twice that of Earth.
Further analysis found reasons to believe that the exoplanet may have a nitrogen-rich atmosphere, similar to that of our home planet.
“This is the first time we have seen a hint of an atmosphere on a rocky or ice-rich habitable-zone exoplanet,” said Ryan MacDonald, NASA Sagan Fellow in the UM Department of Astronomy.
“LHS 1140 b is one of the best small exoplanets in the habitable zone, capable of supporting a thick atmosphere, and we could have found evidence of air on this world.”
These findings suggest that the planet retained a substantial atmosphere and could accommodate liquid water.
And scientists have made another discovery that further supports the ocean theory.
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LHS 1140 b is less dense than expected for an Earth-like planet, indicating that a large fraction of its mass may be contained in water.
This indicates that LHS 1140 b is indeed a water world, likely similar to a snowball with an ocean pointing toward the red dwarf as a target.
Current models indicate that LHS 1140 b could contain an ocean about 4,000 kilometers in diameter, equivalent to half the surface of the Atlantic Ocean.
The surface temperature can be 20 degrees Celsius or 68 degrees Fahrenheit.
What is an exoplanet?
Here’s what you need to know…
- An exoplanet is a planet that is located outside our solar system and orbits its own star, in the same way that Earth orbits the Sun.
- They are very difficult to see with telescopes because they are often hidden by the brightness of their star.
- NASA put the Kepler space telescope into orbit to find Earth-sized exoplanets that could support life
- More than 5,500 exoplanets have been discovered so far, and more missions to find even more exoplanets are planned
- A good way to detect an exoplanet is to look for unstable stars, because a break in starlight can indicate that a planet is orbiting it and therefore occasionally blocking the light.
- Exoplanets are very common in the universe, and the more we discover that they look like Earth, the closer we get to knowing if we are alone out there.
“Our initial reconnaissance of LHS 1140 b with JWST revealed that this is perhaps the best habitable zone exoplanet currently known from atmospheric characterization,” said MacDonald.
“Although we need more JWST observations to confirm the nitrogen-rich atmosphere and to look for other gases, this is a very promising start.”
This story originally appeared on The-sun.com read the full story
