Ethan R. Siegel

Astrophysicist: Ph D.: University of Florida
Blog: Starts with a Bang: Forbes, Scienceblogs
Author: Beyond the Galaxy (WSPC: 2015)
Author: Treknology: The Science of Star Trek from Tricorders to Warp Drive (Voyaguer Press: 2017)

How will humanity first discover ET Life?
Best guess: biosignatures (distant exoplanets)
Here in our own Galaxy, we literally have tens of billions of Earth-like planets around other stars. Planets that are the same size as Earth, that are the same distance from our Earth from our Sun, that orbit around a Sun-like star, capable of (like-) sustaining temperatures for billions or even tens of billions of years. With next generation telescopes, we will be able to tell if they are greening and browning with seasons, and detect oxygen, nitrogen, and carbon dioxide -- signatures of life. This could be our very first hint of life beyond Earth.