NASA has launched the Nancy Grace Roman Space Telescope aboard a SpaceX Falcon Heavy rocket from Florida, marking the beginning of one of the most ambitious astronomical missions ever undertaken. Standing over 12 metres tall and developed over more than a decade at a cost exceeding $4 billion, Roman is designed to survey the cosmos on an unprecedented scale, creating the largest catalogue of astronomical objects ever assembled while probing two of the most fundamental unsolved questions in physics: the nature of dark matter and dark energy.

Roman's defining feature is its extraordinary field of view — between 100 and 200 times wider than that of the Hubble Space Telescope — while still producing images of comparable sharpness and resolution. Equipped with a 300-megapixel camera and a 2.4-metre mirror, the observatory can map the sky roughly 1,000 times faster than Hubble. To put that in perspective, what Roman observes in a single month would take Hubble a century. The telescope will operate from a vantage point 1.5 million kilometres from Earth, which it will take approximately 100 days to reach, and is expected to generate around 1.3 terabytes of data per day — more than Hubble has collected in its entire 35-year operational life.

The mission's primary scientific goals centre on dark matter and dark energy, two phenomena that together are believed to account for roughly 95 percent of the universe yet remain undetected and poorly understood. Dark matter is thought to act as a gravitational scaffold holding galaxies together, while dark energy is believed to be a repulsive force accelerating the universe's expansion. Roman will use its infrared vision to detect light emitted billions of years ago, effectively looking back in time, and will complement existing observatories including the James Webb Space Telescope and ground-based facilities such as the Vera C. Rubin Observatory in Chile and the European Space Agency's Euclid probe. A secondary instrument on board, a coronagraph, will block the intense light of individual stars to reveal orbiting planets — helping scientists expect to discover more than 100,000 new exoplanets, far exceeding the roughly 6,000 identified to date.

The telescope is named after Nancy Grace Roman (1925–2018), a pioneering American astronomer who became NASA's first chief of astronomy and one of the first women to hold an executive position at the agency. Her work in marshalling engineers and scientists to turn visionary ideas into concrete projects earned her the nickname