We all have seen the film “Waterworld” where Earth’s polar ice caps were completely melted, and the sea level had risen to over 5 miles, covering nearly all of the terrain.
Astronomers have discovered a couple of planets that are true “water worlds”. These planets are called exoplanets that contain oceans that are at least 500 times deeper than those on Earth. They have a wet surface on a rocky ball.
These planets are unlike any other found in our solar system.
They are somewhat bigger than Earth yet lack the solidity of rock.
Researchers believe that these planets aren’t likely covered in oceans like some of Kevin Costner’s films, instead, they are covered in an atmosphere of steam.
The water worlds are part of a planetary system that is called Kelper-138.
The Kelper-138 is almost 218 light-years away from Earth in the Lyra constellation.
At the University of Montreal, the planets were studied by the team at the Trottier Institute for Research on Exoplanets using the Hubble and retired Spitzer space telescopes.
In 2014, NASA’s Kepler Space Observatory
saw the planets which must be primarily made of water, as revealed by follow-up measurements made with the Hubble and Spitzer satellite observatories.
However, it was impossible to directly see the spectral sign of water. this is why their density is measured by comparing their mass and size therefore, this determination led to revealing this result.
However, the newly found planets might not have fish in the oceans. The reason is that they are probably too warm and under very high pressure, which makes it difficult to live in them.
Researchers at the University of Montreal discovered that two exoplanets are revolving around the red dwarf star.
On these planets, water covers a large area of the entire planet.
The team of researchers at the University of Montreal published an extensive study of this planetary system called Kelper-138 in the journal” Nature Astronomy”. This research was led by Caroline Piaulet of the Trottier Institute for Research on Exoplanets (iREx).
The researchers observed exoplanets Kepler-138 c and Kepler-138 d with NASA’s Hubble and the retired Spitzer space telescopes. They speculated that the planets could be largely made up of water.
According to reports, water wasn’t directly discovered at Kepler-138 c and d, but with the help of comparing the sizes and masses of the planets to models, astronomers deduce that a substantial fraction of their volume, should be composed of materials that are lighter than rock but heavier than hydrogen or helium.
These materials are spread up to half of the planets. As a result, this could constitute the bulk of gas giant planets like Jupiter. The most common of these candidate materials is water.
The study co-author and professor of astrophysics at the University of Montreal, Björn Benneke described the experience “We previously thought that planets that were a bit larger than Earth were big balls of metal and rock, like scaled-up versions of Earth, and that’s why we called them super-Earths,”
He also explained, “However, we have now shown that these two planets, Kepler-138 c, and d, are quite different in nature and that a big fraction of their entire volume is likely composed of water.
He continued, “It is the best evidence yet for water worlds, a type of planet that was theorized by astronomers to exist for a long time.”
Planets c and d have substantially lower densities than Earth while having volumes that are more than three times as large and masses that are twice as great. This is unexpected considering that the majority of planets that are only marginally larger than Earth that have been thoroughly researched thus far all appeared to be rocky worlds similar to our own. According to experts, several of the icy moons in the outer solar system that also have a rocky core and are mostly made of water would be the most comparable.
The waters on the planets’ surface may not be similar to those on Earth, according to researchers. We anticipate a thick, dense atmosphere formed of steam on Kepler-138 d since the planet’s atmosphere is most likely above the boiling point of water.
Only in that steam environment could there possibly be high-pressure liquid water or even water in another phase that happens at high pressures, known as a supercritical fluid, according to Piaulet.
Astronomers announced the discovery of three planets around Kepler-138 in 2014 thanks to data from NASA’s Kepler Space Telescope. This was predicated on the planet briefly passing in front of their star, which caused a significant reduction in brightness.
Kepler-138 c and d, two potential water planets, are not found in the habitable zone, which is the region surrounding a star where temperatures permit liquid water to exist on the surface of a rocky planet. However, scientists also discovered proof of a brand-new planet in the system, Kepler-138 e, in the habitable zone in the Hubble and Spitzer data.
This recently discovered planet takes 38 days to complete an orbit and is smaller and located farther away from its star than the other three. However, since it doesn’t appear to transit its host star, the nature of this new planet is still unknown. Astronomers may have measured the exoplanet’s size by observing its transit.
Another surprise for the researchers was that, contrary to what was previously believed, the two water worlds Kepler-138 c and d are really “twin” planets, nearly identical in size and mass. On the other hand, Kepler-138 b, the planet that is closer in, is proven to be a tiny Mars-mass planet and one of the tiniest exoplanets that has been discovered so far.