Planets capable of “pivoting” and altering their orientation in short periods of time, at least on a geological scale, could be good candidates to support life as we know it.
According to a model developed by a team of researchers from the NASA Astrobiology Institute, the climatic effects derived from this phenomenon would favor that the water on its surface would remain in a liquid state and would prevent them from becoming covered with ice, even if they were far from its surface. star.
“Until now we would describe these objects as icy worlds, and they would not be a priority in exploration projects,” says Shawn Domagal-Goldman, an astrobiologist with the US space agency. “However, this new approach broadens our idea of what a habitable planet is and where they can be found, ” he adds.
In the essay, published in the journal Astrobiology , the scientists studied the case of a hypothetical body with the same mass as the Earth , located in a system with one or two gas giants, such as Jupiter or Saturn, and presided over by a star similar to the Sun.
Thus, they observed that, on occasion, the gravitational pulls exerted by the large gaseous worlds could change the orientation of the axis of rotation of the object similar to ours even in a few tens of thousands of years, a sigh in geological terms. In fact, in the Upsilon Andromedae binary system, 44 light years away, conditions similar to those described in this model appear to exist.
Researchers ran thousands of simulations with 17 types of planetary assemblages and found that this kind of wobble had a great effect on glaciers in particular, as the amount of light they receive greatly affects how they grow and melt.
As a result, some worlds could hold liquid water on their surface despite being twice as far away from their star as Earth is from the Sun. “In those cases, the so-called habitable zone could extend far beyond what we might expect,” says John Armstrong of Weber State University in Utah, who coordinated the study.
