In the past year, scientists have discovered an astounding number of planets beyond our solar system. On Monday, February 6, Harvard astronomer Dimitar Sasselov will discuss these “exoplanets” and the possibility of discovering life beyond Earth at February’s Frontiers in Astrophysics lecture. Sasselov recently answered a few questions about the search for other worlds.
Have discoveries of exoplanets within the last few months changed any of our views on the potential for life beyond our solar system?
They haven’t overturned any of our views, but they’ve strengthened our understanding that there are plenty of places out there where life could emerge and sustain itself. The question has shifted now from being astronomical—are there habitable planets?—to being biological—what does it take for life to emerge? The new discoveries have also brought about the good news that we should be able to discover and study many nearby planets in the coming few years.
As we search for other life forms beyond Earth, how do we define “life”?
That is the big question. My hope is that the synergy of lab work and exoplanet exploration will bring us a new understanding of the basic nature of life. For the time being, we understand life as a chemical system capable of Darwinian evolution.
How does this moment compare to other breakthroughs in the history of science?
A historic shift in our universal human frame of reference is about to occur, much like the one that occurred 400 years ago with the Copernican Revolution and the creation of classical mechanics. Except this time, it involves life—the synthesis of Darwin’s breakthrough in the 19th century and planetary science of the 21st century.