Looking for Alien Life: Goldilocks Planets and Alien Smog

Superheroes of Science

Are there habitable planets outside of our solar system? Dr. Ravi Kopparapu, Planetary Scientist at NASA Goddard, explains that almost every star in our galaxy has a planet around it. This means there may be 100 billion planets in our Milky Way galaxy! Most of these planets range between the sizes of Earth and Neptune. Data available to exoplanet scientists is limited to what can be collected through remote observations with telescopes. Therefore, scientists tend to focus on terrestrial planets (similar to Earth), with suitable atmospheres (nitrogen and oxygen), that are able to maintain liquid water on the planet’s surface. A biological presence could interact and change the gas composition of the atmosphere, which could then be detected by remote telescopes and lead to potential discoveries of life.