Since the world is a world, the first humans were already fascinated by the sky and the stars that were seen. As technology advanced and scientific thinking became more elaborate, the enchantment of space and environments around the universe only increased. Of course, with the fascination with space and the increase in resources, the fascination with the possibility of life beyond Earth has also grown.
Of course, for complex life to exist elsewhere than on Earth requires several factors, but scientists seem to have found the feature crucial to this. It is the way a planet is tilted on its axis of rotation relative to its orbital plane around a star. This is known as axial tilt.
According to a new study, a modest axial tilt, like that of our planet , helps increase the production of oxygen that is vital to life as we know it. And planets that have this tilt or too small or too large may not be able to produce enough oxygen for complex life to thrive.
“The end result is that worlds that are modestly tilted on their axes may be more likely to develop complex life. This helps us narrow the search for complex, perhaps even intelligent, life in the Universe,” said planetary scientist Stephanie Olson of Purdue University.
Obviously it is possible for life to arise outside known parameters on Earth. But since it’s the only planet known for sure to harbor life, it’s convenient for researchers to model research after Earth.
When looking for life outside Earth, the first thing researchers look for is whether the planet is relatively small and rocky like ours. In addition to seeing if it orbits the star at a distance called the habitable zone, where temperatures allow liquid water to enter the surface.
These factors are good to analyze, but those that contribute to the emergence of life are probably far more complex. For example, the presence of a magnetic field is considered quite important because it protects the planetary atmosphere from stellar winds. Besides the eccentricity of the planet’s orbit and what kind of other planets are present in your system are also quite important factors.
The factor that Olson and his team noticed the most was the presence and production of oxygen. More specifically, conditions on the planet that can impact the amount of oxygen that is produced by photosynthetic life .
The researchers’ goal is to understand how the conditions where cyanobacteria could thrive came about. They do this through modeling.
“The model allows us to change things like the length of the day, the amount of atmosphere or the distribution of the earth to see how marine environments and oxygen-producing life in the oceans respond,” explained Olson.
This model showed that several factors may have influenced the transport of nutrients in the oceans in such a way that they contributed to the emergence of oxygen-producing organisms, such as cyanobacteria.
Out Of Earth
Over time, the Earth’s rotation slowed, days got longer, and continents formed and migrated. The researchers found that all these changes could have helped increase oxygen.
Another factor considered was the axial inclination. Our planet’s axis is not exactly perpendicular to its orbital plane around the sun. It is tilted at an angle of 23.5 degrees from the perpendicular. It is this inclination that gives us the seasons. And temperature changes also influence the oceans, resulting in convective mixing and currents and nutrient availability.
Given all of this, it is perhaps not so surprising that axial tilt has such a significant effect on oxygen production.
“The greater slope increased photosynthetic oxygen production in the ocean in our model, in part increasing the efficiency with which biological ingredients are recycled. The effect was similar to doubling the amount of life-sustaining nutrients,” explained University of Chicago planetary scientist Megan Barnett.
This is another parameter that researchers can use to help them narrow down planets in other galaxies where there is likely to be life as we know it.