[00:00.00]Researchers say new telescope observations suggest an Earth-like planet outside our solar system may hold a large liquid ocean.
[00:15.49]The exoplanet is known as LHS 1140 b. Astronomers believe it sits about 48 light years away from Earth.
[00:30.02]A light year is the distance light travels in a year - about 9.5 trillion kilometers.
[00:39.61]The research - led by astronomers at the University of Montreal in Canada - shows the possibility the exoplanet might hold the right conditions to support some form of life.
[00:57.24]A study explaining the findings recently appeared in The Astrophysical Journal Letters.
[01:06.18]The study is based on observations collected in December 2023 by the James Webb Space Telescope.
[01:17.51]The American space agency NASA operates the orbiting observatory.
[01:24.66]Researchers combined the information from the James Webb with existing data to make new estimates for the exoplanet's mass and size.
[01:39.22]These suggest that LHS 1140 b is "a promising super-Earth ice or water world," the University of Montreal said in a statement.
[01:56.06]Some past studies had suggested the exoplanet might be a gas giant, also known as a mini-Neptune.
[02:07.14]But the researchers said the new study provides evidence that LHS 1140 b is more likely a super-Earth, a rocky planet bigger than Earth.
[02:23.63]The new research supports a NASA-led study from October 2023 that suggested at least 17 observed exoplanets could hold oceans of liquid water.
[02:40.22]That study noted that sometimes water from these oceans likely breaks through large pieces of ice to form geysers.
[02:53.31]Scientists had already identified LHS 1140 b as being within its star's "habitable zone."
[03:04.88]Exoplanets found within this zone are believed to have temperatures that would permit water to exist in liquid form.
[03:15.68]Measurements made by the James Webb data suggest the exoplanet "is less dense" than expected for a rocky, Earth-like body.
[03:29.53]The researchers estimated that 10 to 20 percent of LHS 1140 b's mass might be made up of water.
[03:41.04]The possibility of a large liquid ocean would be found on the side of the planet always facing the star that it orbits.
[03:52.22]The new data collected by the James Webb showed the exoplanet might also have a nitrogen-rich atmosphere.
[04:02.46]This differs from earlier research that suggested a possible atmosphere that was mostly hydrogen.
[04:12.26]Charles Cadieux is a doctoral student at the University of Montreal's Trottier Institute for Research on Exoplanets.
[04:24.59]He was the lead writer of the study.
[04:27.86]Cadieux said in a statement, "Of all currently known temperate exoplanets, LHS 1140 b could well be our best bet to one day indirectly confirm liquid water on the surface of an alien world beyond our solar system."
[04:50.98]He noted that if the study's findings can be confirmed, the data would represent "a major milestone" in the search for exoplanets that could possibly support life.
[05:06.73]René Doyon is a project scientist at the University of Montreal.
[05:13.95]He helped lead the research. He said more observations will be needed to confirm the current study's findings.
[05:24.28]"The current hint of a nitrogen-rich atmosphere begs for confirmation with more data," Doyon said.
[05:34.75]He estimated that at least one more year of observations will be needed "to confirm that LHS 1140 b has an atmosphere."
[05:48.07]The process of confirming whether carbon dioxide is present in the atmosphere and liquid water exists on the surface would likely require several years of observations, Doyon noted.
[06:04.76]Ryan MacDonald is a NASA Sagan Fellow in the University of Michigan's Department of Astronomy who helped examine the James Webb data.
[06:17.82]He said, "This is the first time we have ever seen a hint of an atmosphere on a habitable zone rocky or ice-rich exoplanet."
[06:29.98]With further data collection and investigation, MacDonald noted there is a good possibility "we might just have found evidence of air on this world."
[06:44.67]I'm Bryan Lynn.
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Words in This Story
geyser - n. a hole in the ground from which hot water and steam come out
habitable - adj. able to support life
best bet - idiom. the action that is most likely to be successful
alien - n. relating to creatures from another planet
milestone - n. an important event in the development or history of something
hint - n. to suggest or indicate something in an indirect way
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