NASA's Roman telescope set to launch on Falcon Heavy

NASA is set to launch its next great space observatory Sunday morning. The Nancy Grace Roman Space Telescope lifts off at 7:26 a.m. Eastern from Kennedy Space Center in Florida. It rides a SpaceX Falcon Heavy rocket. Roman carries a mirror as big as Hubble's. But its camera sees roughly 100 times more sky in a single shot. Its main job is hunting for dark energy, the mysterious force that's pushing the universe apart.

Dark energy is one of the biggest mysteries in physics. Scientists know something is pushing galaxies apart faster over time, but nobody knows what that something is. Roman will map millions of galaxies to track how that push has changed over billions of years. It will also survey for planets outside our solar system using a technique called gravitational microlensing. That method can spot planets too small or too far away for other telescopes to see. Roman's mission is designed to complement, not replace, Hubble and the James Webb Space Telescope.

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Will Roman actually get off the ground on schedule? Space launches slip often. Falcon Heavy missions carrying billion-dollar payloads get scrutinized closely before liftoff is confirmed. Once Roman reaches orbit, it still needs months of instrument checkout before it starts real science. If that goes well, Roman should start returning its first images before too long. The telescope could reshape how we understand the universe's biggest mystery. Why is the universe expanding faster over time?