Artistic vision of the Earth as a frigid planet in a snowball state. A new study indicates that aspects of axial tilt or planetary orbit can create a similar condition where oceans freeze and life cannot appear.
Researchers from Washington report that the aspects of tilt and orbital dynamics in planetary geometry can seriously affect the potential suitability of the planet for habitat. It can even lead to a “snowball” state, where the oceans freeze and there is no possibility of surface life.
The new analysis shows that the placement of the planet in the habitat zone (there is a possibility for the presence of liquid water) is not always sufficient evidence of the assessment of potential habitability. For the study they used computer simulation, having considered how two functions (the planet's inclination and eccentricity of the orbit) affect the potential of life. They were limited to planets in the habitats of G-dwarfs.
The inclination of the planet is its inclination relative to the axis of the orbit, which controls the seasons. Orbital eccentricity - form (circular, elliptical, oval) orbits. The Earth feels comfortable, because it revolves around the Sun with an axial tilt of 23.5 degrees, swaying weakly for thousands of years. But what happens if these vibrations are stronger? Early studies have shown that more severe axial tendencies in the habitat zone will make the world warmer. However, in a new analysis, researchers were surprised to find that the opposite reaction would be true. Such worlds are capable of entering into a snowball state if the inclination of the planet is increased by more than 35 degrees.
New research helps to understand the controversial ideas considered in the past. For this purpose, complex processing of ice cover growth and retreat in planetary modeling were used, which is a significant improvement over previous analyzes.
It turns out that the glacial periods on exoplanets may exceed earthly ones in severity, and the orbital dynamics can be the main factor in the habitability of the planet. Such a simulation will allow us to understand which planets are worthy of telescopic attention, which will significantly save time and resources.