A new study examining the dynamics of two potentially habitable exoplanets hundreds of light-years away from Earth has shown that the climate on these worlds could be stable, similar to Earth's.
Identified over Four Years The Kepler-186f and Kepler-62f exoplanets sit in the habitable zone or so-called "Goldilocks" zone of their host stars – the place where the amount of star warming that reaches a planet is just enough, Collecting Liquid Water
While the ability to house liquid water makes these worlds particular candidates for attention, it is not the only thing needed to create conditions for habitability. Factors such as climate and the ability to hold on to an atmosphere also play an important role, prompting researchers at the Georgia Technical University to study thoroughly. [1
To understand the climatic conditions prevailing on the two exoplanets, the group conducted a series of simulations to study the dynamics and evolution of their axial tilt.
Angle, where the axis of a planet is tilted, determines how much starlight reaches the surface. This drastically affects the regulation of the climate and seasons in the world in question. For example, if the axial slope varies greatly, the climate on a planet could be very unstable, just as it was on Mars.
"Mars is in our solar system in the habitable zone, but in its axial system The inclination was very unstable – from zero to 60 degrees," said Gongjie Li, the lead author of the study, in a statement. "This instability has probably contributed to the decay of the Martian atmosphere and the evaporation of surface water."
However, this is not the case for the two exoplanets, the researchers found. According to their simulations, Kepler-186f and Kepler-62f have a much smaller pitch variation of the axles, suggesting that the climate is stable and the seasons on both worlds are regular, similar to Earth's. The axis inclination of the planet moves about every 10,000 years between 22.1 and 24.5 degrees back and forth.
"Our study is one of the first to study the climate stability of exoplanets and contribute to the growing understanding of these potentially habitable nearby worlds," Li added in the statement. Although this discovery does not suggest that the two exoplanets can harbor life, it suggests that they are well suited to this possibility.
Axial slope variations are, as the researchers have described, a result of the interaction between bodies in the same system. When planets interact, the resulting gravitational influence can cause the orientation angle of their orbit to oscillate. And if the speed of this oscillation is equal to the precession of the axis of rotation of the planet (as seen in the orbital motion of a gyroscope), the axis of the planet can undergo dramatic variations.
Our neighboring planets are subject to the same interaction, but the Earth has a large moon that increases the precession of the spin axis of our planets and ensures that it differs from the vibrational frequency of the orbit. In this way, it stabilizes the variation of our axial tilt relative to that of Mars and provides us with stable climatic conditions.
"It seems that both exoplanets are very different from Mars and Earth because they have a weaker connection to their sibling planets," Li added. "We do not know if they have moons, but our calculations show that the spin axes It also concluded that without Kepler-186f and 62f satellites would have remained constant over millions of years, "he concluded.
The study" Obliquity Variations of Habitable Zone Planets Kepler 62-f and Kepler 186-f "was published in the Astronomical Journal. 19659016]