Roman Telescope to Map Cosmic Voids Down to 20 Million Light-Years

NASA's Nancy Grace Roman Space Telescope will detect and measure tens of thousands of cosmic voids upon launch, resolving structures as small as 20 million light-years across. Current ground-based surveys typically resolve voids hundreds of millions of light-years wide. Roman's wide-field capabilities will enable researchers to map void density profiles and distribution with unprecedented precision, constraining measurements of cosmic expansion and structure formation across 95% of the universe's volume.