Scientists believe that the presence of life can affect the speed of rotation of the planet around its own axis.
Currently, the Earth rotates around its own axis with a period of 24 hours, but earlier our planet rotated with a period of only 2-3 hours. Over time, the planet's rotation slowed down due to the so-called "tidal braking" caused by the action of gravity from the Moon and the Sun. However, according to scientists led by Caleb Scharf, head of the Department of Astrobiology at Columbia University, USA, the planet's atmosphere is capable of partially compensating for this gravitational effect, which slows down rotation.
Under the influence of solar radiation on the daytime side of the Earth, the atmosphere heats up and becomes less dense, while on the nighttime, cold side of the planet, the density of the atmosphere is increased. This creates a "lever" for gravitational action, which, according to Scharf and his colleagues, slows down the deceleration of the Earth's rotation by the gravity of the Moon.
The composition of a planet's atmosphere can affect the rate at which it heats up and cools. For example, ozone, generated from oxygen by ultraviolet radiation, absorbs sunlight well and helps "warm up" the planet. Therefore, the oxygen released by hypothetical life forms that inhabit the exoplanet can be converted into ozone, which, by changing the mode of heating of the planet's atmosphere by the parent star, will thereby affect the planet's rotation rate, slightly accelerating its rotation around its own axis, Caleb suggests.
The study was published in the journal Astrobiology.