Taking a picture of a planet around another star is extremely difficult. The star is very bright, while the planet is small and dark. It is like trying to see a tiny firefly next to a powerful light from many kilometers away.

NASA’s Nancy Grace Roman Space Telescope will solve this problem with its Coronagraph Instrument. First, special masks block most of the star’s light. However, some light can still bend around the masks or spread because of tiny problems in the telescope’s mirrors.

To remove this extra light, Roman uses two “deformable mirrors.” Thousands of small parts behind these mirrors can move like tiny pistons. They change the mirrors’ shape in real time and correct very small errors in the incoming light. Other masks then reduce the remaining starlight. Finally, a sensitive camera records the weak light reflected by a planet. Computer processing makes the image even clearer. (science.nasa.gov)

Roman’s coronagraph is designed to see planets that are about 100 million times fainter than their stars. It may directly photograph large gas planets that are similar to Jupiter in size, temperature, and distance from their parent stars. Unlike many planets photographed before, these worlds may be older and colder. Roman will observe them in visible light, so it will detect starlight reflected from their clouds or surfaces. The planets will probably appear as small points of light, not as detailed round worlds. (science.nasa.gov)

Roman launched on August 30, 2026, and its Coronagraph Instrument was successfully powered on two days later. The telescope is now traveling toward its observation area while engineers test and adjust its systems. (nasa.gov)

This instrument is mainly a technology test, but its success could help future telescopes take pictures of smaller, more Earth-like planets—and perhaps search their atmospheres for signs of life.