Mirror Assembly for Roman Space Telescope Arrives to NASA Goddard

This footage depicts the mirror assembly for the Nancy Grace Roman Space Telescope arriving at NASA's Goddard Space Flight Center. It is transported at night to accommodate the slow-moving specialized transport vehicle called the "Chariot."

Within hours of arriving, the lid of the Chariot was removed, and the lower portion was pushed into NASA's largest cleanroom for further unpacking.

Designed and built by L3Harris Technologies in Rochester, New York, the assembly incorporates key optics (including the primary mirror) that were made available to NASA by the National Reconnaissance Office. The team at L3Harris then reshaped the mirror and built upon the inherited hardware to ensure it would meet Roman's specifications for expansive, sensitive infrared observations.

Roman's primary mirror is 7.9 feet (2.4 meters) across. While it's the same size as the Hubble Space Telescope's main mirror, it is less than one-fourth the weight. Roman's mirror weighs only 410 pounds (186 kilograms) thanks to major improvements in technology.

The newly resurfaced mirror sports a layer of silver less than 400 nanometers thick – about 200 times thinner than a human hair. The silver coating was specifically chosen for Roman because of how well it reflects near-infrared light. 

The primary mirror, in concert with other optics, will send light to Roman's two science instruments – the Wide Field Instrument and Coronagraph Instrument. The first is essentially a giant 300-megapixel camera that provides the same sharp resolution as Hubble across nearly 100 times the field of view. Using this instrument, scientists will be able to map the structure and distribution of invisible dark matter, study planetary systems around other stars, and explore how the universe evolved to its present state.