Where did we come from? How did we get here? Are we alone?

At its core, astronomy is the science tasked with addressing these existential questions that lie at the heart of what it means to be human. And for more than a quarter century one observatory more than any other has brought us closer to answers: The Hubble Space Telescope.

Stationed in low Earth orbit above the starlight-scattering atmosphere, Hubble’s 2.4-meter mirror and state-of-the-art instruments have allowed scientists to glimpse far-distant galaxies formed in the universe’s infancy, the births of stars right here in our own Milky Way and even a handful of worlds orbiting other suns. With each groundbreaking observation, Hubble helped fill in details of what might be the greatest story ever to be told: How galaxies, stars, planets and ultimately life itself emerged from the big bang’s primordial chaos. But Hubble is reaching its limits, leaving us just on the cusp of peering farther into the unknown. A successor 100 times more powerful—the James Webb Space Telescope—will launch in 2018 to continue the revolution in astronomy that Hubble began, says NASA astrophysicist and Webb deputy project scientist Amber Straughn.

Join Straughn this evening at the Perimeter Institute for Theoretical Physics in Ontario for a behind-the-scenes look at Webb’s immense scientific promise—and the immense technical challenges NASA overcame to build it. In a special presentation that will be broadcast live at 7 P.M. Eastern time on this page, Straughn will explain how Webb will unveil the universe’s very first stars and galaxies, and how it might even find the first signs of extraterrestrial life on planets beyond our solar system. The talk, “A New Era in Astronomy,” is part of Perimeter’s public lecture series presented by BMO Financial. Online viewers can pose questions by tweeting to @Perimeter using the #piLIVE hashtag.