Earth is a great place for life to survive and thrive. For starters, it has liquid water on its surface, it’s just the right distance from the Sun, has a protective atmosphere filled with gases, and it’s equipped with a magnetic field to shield us from dangers like solar flares.
Surely, some might say, it must be an unbelievably rare occurrence to have such an ideal setting for life as we know it, even within the limitless bounds of the universe. However, this might not be the case.
A new piece of research suggests that it’s likely other planets are out there with better conditions for life to thrive than those on Earth. As such, they could even have a greater variety of life than exists on Earth.
Presenting their work in a Keynote Lecture at the Goldschmidt Geochemistry Congress in Barcelona, Dr Stephanie Olson of the University of Chicago explains how their team modeled likely conditions on different types of exoplanets using NASA-developed computer software to simulate the habitats that could theoretically exist on exoplanets. The work primarily focused on oceans since liquid water is essential for the kind of delicate chemistry that makes life possible (at least, based on our own planet’s lifeforms).
"Life in Earth's oceans depends on upwelling (upward flow) which returns nutrients from the dark depths of the ocean to the sunlit portions of the ocean where photosynthetic life lives," Dr Olson said during their lecture at the Goldschmidt Geochemistry Congress. “More upwelling means more nutrient resupply, which means more biological activity. These are the conditions we need to look for on exoplanets."
Scientists have previously hinted at the possibility that some exoplanets might have colossal continents and vast oceans, but we don’t yet have the technology to gather direct evidence of this. While that dream is still out of reach, for now this new research could help astronomers determine what kind of exoplanets to look for.
"We have used an ocean circulation model to identify which planets will have the most efficient upwelling and thus offer particularly hospitable oceans,” Olson continued. “We found that higher atmospheric density, slower rotation rates, and the presence of continents all yield higher upwelling rates. A further implication is that Earth might not be optimally habitable – and life elsewhere may enjoy a planet that is even more hospitable than our own.”
Of course, this is all theoretical so far, but hey – I want to believe.