Scientists believe that some potentially habitable planets are tidally locked, with one side permanently facing their star. This means one hemisphere experiences eternal daylight, while the other is in perpetual darkness.

Research on Earth’s organisms living in sun-deprived environments shows that the absence of sunlight doesn’t hinder life. Such creatures offer a glimpse into what alien life without a circadian rhythm might look like, according to Marie Cohen from the Open University in the UK.

Researchers estimate that our Milky Way galaxy, which contains between 100 and 400 billion stars, hosts billions of potentially habitable planets.

Around 70% of the stars in the Milky Way are red dwarfs, and about 40% of them have at least one planet orbiting within their habitable zone. This means these planets could potentially have liquid water on their surface, increasing the chances of life.

However, rocky planets orbiting red dwarfs differ from Earth. Red dwarfs are cooler than the Sun, so their planets orbit closer, experiencing stronger gravitational forces.

As a result, many of these planets are tidally locked, with one side always facing their star, similar to how the Moon always shows the same face to Earth.