# Coronagraph Instrument (CGI)

Roman’s second instrument blocks a star’s glare so the faint reflected light of nearby giant planets and dusty disks can be seen directly.

It carries deformable mirrors and advanced masks that actively correct starlight, aiming for contrast far beyond any coronagraph flown before. It works in visible light, roughly 0.4 to 1.0 microns, with imaging, spectroscopic and polarimetric modes.

Its goal is to show these technologies work in space — a stepping stone to NASA’s proposed Habitable Worlds Observatory, which would try to image Earth-like planets around Sun-like stars.

- **Type:** Technology demonstration
- **Wavelengths:** ≈ 0.4–1.0 µm
- **Modes:** Imaging, spectroscopy, polarimetry
- **Built by:** NASA JPL