Signs of life on exomoons a distinct possibility too

Although we are yet to witness an exomoon, there are far greater chances for exomoons to harbour life like exoplanets, a thrilling research has indicated.

Researchers at University of Edinburgh have highlighted various factors that may make an exomoon more or less habitable.

They investigated how the climate of an exomoon will be affected by tidal stresses which provide a source of internal heating for the exomoon as it is stretched and deformed by the gravitational pull of its planet.

They also investigated how light reflected from the exoplanet, and eclipses by the exoplanet, can also subtly alter the exomoon's climate.

The reseachers Duncan Forgan and Vergil Yotov classified exomoons into "habitable", "hot", "snowball" or "transient" categories.

Exomoons in the fourth, transient class are on average habitable but the amount of habitable surface area varies widely with time, said a report in the journal Conversation.

There are various techniques proposed to find habitable exomoons.

One way is by studying the effects that an exomoon will have on the exoplanet it is orbiting.

"Overall, the research shows that exomoon climates are rather more complex than previous research has supposed," the report added.

An exomoon, or extrasolar moon, is a natural satellite that orbits an exoplanet or other extrasolar body.

So far, scientists have discovered over 1,000 exoplanets but only a few of them are believed to be habitable.

Perhaps the most habitable planet found till date is the recently announced Kepler-186f, an earth-sized planet.