Life beyond earth? Water-rich exoplanets discovered outside our solar system: Report

In a major accomplishment in the investigation of life beyond our Earth, researchers have found a third category of exoplanets – rich in water – revolving around the red dwarf stars, the most common and long-lived stars. It is an epochal step because, for the first time, the habitability of other planets can be scientifically proven, a report in Popular Science says.

What are exoplanets?

According to the National Aeronautics and Space Administration (NASA), an exoplanet is a planet that is orbiting other stars beyond our solar system.

Nasa’s Kepler Space Telescope has shown that the galaxy has more numbers of planets than stars. The elements of some of these planets are similar to the planets of our solar system, although they do not necessarily revolve around any stars, as there are some exoplanets which are free floating and orbit around the galactic centre.

Nasa estimates that apart from iron or carbon, some may have an abundance of water or ice.

What are the two category of planets?

Astronomers have long divided the planets into two categories based on their radii – rocky planets with shorter radius and gaseous planets with larger radius.

Although water is found on Earth, it is placed into the category of rocky planets because water amounts to only 0.02 percent of its total weight.

Experts believed that the reason behind the difference in radii is the varied effect on erosion of a planet’s atmosphere due to the star’s radiation, around which the planets are rotating.

Rocky planets were left with very thin atmospheres, making up a largely exposed rocky surface. Gaseous stars had larger radii because they were able to keep thick, puffy atmospheres.

What is the new finding?

However, in the new study published in the journal Science on September 8, researchers have categorised the planets based on density rather than radius, adding one more category of water-rich planets.

The report says that these types of exoplanets are alien to us because we don’t have any such similar planets in our solar system. This new founding is tantalising the astronomers in the hope of a life beyond Earth. Water is considered as the prerequisite for life, though not a sufficient condition to foster habitation.

The report says that although water is present on the planet; it is not in the form found here on Earth. The sample suggests that the water cannot be on the surface, but either in combined form with magma or trapped below the surface.

The exuberant researchers are expecting to find more about these exoplanets by focusing the James Webb Space Telescope (JWST) to investigate the possibility of habitation on other planets.