How do we find life outside our solar system? We start by looking for planets that resemble Earth, the only planet we know of that is habitable. This means we look for planets that are roughly the same size as Earth and orbit the right distance from their star to support liquid water at the surface, known as the habitable zone. Early planet hunters, like NASA’s Kepler/K2 mission, have discovered thousands of planets orbiting distant stars, including several that are small, like Earth, and reside in their star’s habitable zone. NASA’s Transiting Exoplanet Survey Satellite (TESS), will search for small planets that orbit stars in our solar neighborhood. Because these planets are much closer to us than the planets discovered by Kepler/K2, astronomers will be better able to characterize them and potentially find some with solid surfaces and detectable atmospheres.
The planets TESS discovers will be the touchstone planets for many years to come, allowing more powerful telescopes like the upcoming James Webb Space Telescope to look at them in greater detail. The Webb telescope will be able to probe planet atmospheres and look for biosignatures that could only be attributed to life on that planet. Future missions may one day directly image other planets, allowing researchers to complete a census of our galaxy and better understand not only if other habitable planets exist, but how common they are.
Key Questions Guiding SEEC Research
By studying ways that biospheres interact with planetary environments, SEEC researchers are pioneering methods to detect life on other worlds.
A vast multitude of physical, chemical, and geological processes combine to produce the characteristics of a specific exoplanet’s atmosphere and surface that will be visible to future telescopes.
Planetary habitability results from a complex network of interactions between the planet, its planetary system, and host star.
In our quest to find life outside of our solar system, we look for planets that resemble Earth, the only planet that we know of that is habitable.
Earth is our only example of a planet that is habitable and inhabited, and as such represents the archetypical habitable environment for remote sensing and mission development studies.