Trond Helge Torsvik - Planetary Habitability

The idea that worlds around other stars could develop and maintain environments hospitable to life ― in a way like our planet ― has captivated scientists for centuries. Yet, to investigate this question, we must recognize and characterize the key conditions that make a planet habitable. This endeavour is the prime objective for the Centre for Planetary Habitability (PHAB). The only planet on which life is known to have originated (Earth) appears unique in many ways, including the presence of abundant surface water, a large moon, a long-lived magnetic field, and plate tectonics. Yet, which of these and other characteristics are essential for its long-term habitability? Equally, how have Earth’s physical and chemical attributes, and thus our planet’s proclivity for life, evolved? How can we recognize distant worlds around other stars that have been or could be habitable? These questions, and a new understanding of planetary habitability unfolding from them, are especially important as we now embark on an unprecedented era of exploration and discovery of extra-solar planetary systems.