Are we alone in the universe? Revisiting the Drake equation – Exoplanet Exploration: Planets Beyond our Solar System
![The search for habitable planets with biosignature gases framed by a 'Biosignature Drake Equation' | International Journal of Astrobiology | Cambridge Core The search for habitable planets with biosignature gases framed by a 'Biosignature Drake Equation' | International Journal of Astrobiology | Cambridge Core](https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20180904130652529-0254:S1473550417000052:S1473550417000052_fig1g.jpeg?pub-status=live)
The search for habitable planets with biosignature gases framed by a 'Biosignature Drake Equation' | International Journal of Astrobiology | Cambridge Core
![Choose Your Own Alien Adventure – The Drake Equation Gets Interactive | Smart News | Smithsonian Magazine Choose Your Own Alien Adventure – The Drake Equation Gets Interactive | Smart News | Smithsonian Magazine](https://thumbs-prod.si-cdn.com/om-3NH-bNGlA3T9-HE8Q3Y1q5CE=/fit-in/1600x0/https://public-media.si-cdn.com/filer/20120824114005drake.png)