NASA is getting ready to launch the Nancy Grace Roman Space Telescope, a next-generation observatory to study dark energy, dark matter, gravity and planets outside the Solar System. It is named after Nancy Grace Roman, NASA's first chief astronomer, and succeeds Hubble (1990) and James Webb (2021). It will fly on a SpaceX Falcon Heavy from Kennedy Space Centre, Florida, to Lagrange Point 2, about 1.6 million km from Earth. Its main survey is expected to cover more than two billion galaxies to trace cosmic expansion.