Laurence Perreault-Levasseur

Light born at the moment of the Big Bang has traveled to us for almost 14 billion years. But along the way, it passed through the gravitational fields of galaxies and clumps of dark matter, which bent its rays. To an observer, this looks like an image stretched and smudged by an old window pane.

Two hundred million stars. In the heart of the Galaxy, where the future survey by the Nancy Grace Roman telescope will aim, about 250 times during its mission the light of one of them will flicker at an invisible touch.