Exoplanets with ‘terminator zones’ may be able to host life, study finds

An artistic depiction of a planet with a habitable terminator. (Ana H Lobo / FOX Weather) A recent study shows that "terminator zones" on rocky planets outside our solar system may have the potential to harbor life.Unlike Earth, these exoplanets have one side that experiences permanent daytime and another with permanent nighttime.

The region where the two sides meet is called the terminator zone."Much like the equator is a band between the northern and southern hemisphere on Earth, the terminator is a band that separates the permanent dayside and the permanent nightside of these planets," said Ana Lobo, physics and astronomy researcher at the University of California at Irvine and lead on the new study.An exoplanet’s terminator zone, along with its perpetual dayside and nightside, is made possible by the planet’s proximity to its star.  NASA FINDS ‘TURBULENT SKIES' WITH CLOUDS, WATER MOLECULES ON EXOPLANETAccording to Lobo, planets included in their study closely orbit smaller, dimmer stars known as red or M-dwarf stars.

The orbits are quite small, bringing the planets closer to their stars than Mercury is to the sun.Because of this proximity, the star of a planet with a terminator zone has a strong gravitational pull on the planet, slowing down its rotation.

The rotation becomes so slow that the same side of the planet constantly faces the star. Called tidal locking, this phenomenon is also seen with Earth and the moon, Lobo said.Waxing gibbous moon is seen over Panama City on July 29, 2020.(Photo by Luis Acosta/AFP via Getty Images) This tidal locking results in the permanent dayside and nighttime on these planets.