A new type of exoplanet has been identified

Cambridge University astronomer Nick Madhusudan and his colleagues explain that these hot planets are covered by oceans and have a hydrogen-rich atmosphere.

These sea worlds (Ocean planets, In English) similar to other planets Super Earth And this Mini-NeptuneAnd may be 2.6 times the size of Earth. They reach atmospheric temperatures of about 200 degrees Celsius, but their oceans, like those on Earth, may be ideal for microbial life.

The artistic representation of Exoplanet K2-18b was discovered in 2016 by researchers at the Exoplanets Research Institute. It belongs to a new type of exoplanet.

Photo: UdM / ALex Boersma

Such planets, which are not in our solar system, are very abundant in our Milky Way galaxy.

Many of these planets are larger and warmer than Earth, but have the property of retaining large oceans, such as microorganisms found in some of Earth’s extreme water environments.Explain the researchers in a press release issued by the university.

Most of the asteroids discovered in the last 30 years are between the size of Earth and Neptune. They may be rock or ice giants with hydrogen-rich atmospheres or intermediate planets.

Most mini-Neptunes are 1.6 times the size of Earth: they are smaller than Neptune, but larger enough to have an Earth-like rock interior.

If the work carried out to date reveals that the pressure and temperature under their hydrogen-rich atmosphere will be too high to support life, the work of the British team dedicated to the Mini-Neptune K2-18b suggests that these planets could be life-threatening.

These results led researchers to conduct a detailed study of all the planetary and stellar properties that meet these conditions, so that known exoplanets could observe the biological signatures of life there.

It was this mission that helped British astronomers identify these new types of planets. In these exoplanets, we also see the marine worlds being manipulated by waves, which can provide the conditions for their permanent night life and survival only in the marine worlds. Cold They receive little radiation from their star.

Planets of this size dominate the known populations of the Exoplanets, although they have not been studied as extensively as Super-Earths., Add astronomers.

Size alone is not enough to confirm whether a planet belongs to a new type. Other features such as mass, temperature and atmospheric properties must be confirmed.

The Cambridge team succeeded in identifying a model of the planets suitable for the new type. They are the main candidates for a comprehensive study with next-generation telescopes such as the James Webb Space Telescope (TSJW), which will be launched in November.

All of these planets orbit red dwarf stars 35 and 150 light-years apart. They are therefore close by astronomical standards. Observations already planned by JWST of the most promising candidate K2-18b may lead to the detection of one or more biologically signed molecules., Say researchers.

Finding a living signature will change our understanding of cosmic life, Nikku Madhusudan added. As nature continues to amaze us in ways we can’t even imagine, we need to be open about where we can find life and what form that life will take.

Details of this work have been publishedJournal of Astronomy (New window) (In English).