The big questions that challenge the field of astrobiology are as old as humanity: Are we alone in the Universe and how did life on Earth begin?

There are no firm answers to those questions yet, but the intensity and breadth of the effort was on display April 24-28 when more than 800 scientists gathered for the biennial Astrobiology Science Conference (AbSciCon), this year held in Mesa, Arizona. All the technical talks, plenaries and endless exchanges and debates among scientists highlighted how much the field has evolved, with some consensus forming around a few fundamental themes.

When it comes to extraterrestrial life, no longer is the main question whether bodies like Mars or the outer Solar System’s icy moons could be habitable. Rather, researchers have moved on to determining how they can find evidence of life, past or present, through the presence of bio-signatures and other techniques.