NASA’s Nancy Grace Roman Space Telescope opened its Coronagraph Instrument to cosmic light on September 22, 2026, marking the first time in orbit that an active, shape-shifting mirror system has successfully captured starlight. The milestone follows successful stability tests of the observatory’s fine-guidance system as it travels toward Lagrange point L2.
One month after launching aboard a SpaceX Falcon Heavy on August 30, 2026, NASA’s Nancy Grace Roman Space Telescope reached a major technical milestone. Designed and built by NASA’s Jet Propulsion Laboratory in Southern California, the coronagraph will demonstrate cutting-edge technology to block starlight and view planets and dusty disks around nearby stars. The observatory woke up its Coronagraph Instrument on September 1 and stretched its digital, electronic, and mechanical systems through mid-month. On September 22, the instrument opened its eyes to cosmic light for the very first time, followed by a second, sharper observation on September 27.
Fine-Guidance System Tests Hold the Observatory Steady
Before the coronagraph could capture its first light, engineers had to prove the observatory could remain locked onto targets with microscopic precision. A coronagraph requires extreme stability because any drift, vibration, or pointing error allows unwanted starlight to flood the image and overwhelm the faint planets scientists want to detect.
Between September 15 and 21, Roman’s fine-guidance system completed a successful series of tests. The system dedicates a small portion of each of the Wide Field Instrument’s 18 detectors to rapidly monitor guide stars with known positions. The fine-guidance system reports these star positions about four times each second to the attitude control system, which applies tiny corrective nudges to counter any drift.
Tests confirmed that the observatory can maintain stability better than 1/100,000 of a degree for half an hour at a time during Wide Field Instrument observations, or for up to eight hours at a time during longer coronagraph observations. Engineers note this level of stability is equivalent to keeping a laser focused on a U.S. dime from about 150 miles away, with goals to push that performance even further to roughly 230 miles.
Deformable Mirrors and Precision Piezo Actuators Power the Coronagraph
Unlike the Hubble Space Telescope and the James Webb Space Telescope, Roman’s coronagraph uses an active, shape-shifting mirror system. This system uses pistons to physically reshape the mirror surfaces in real time to compensate for optical errors, thermal fluctuations, and mechanical vibrations.
High-performance piezo actuators also drive the fast steering mirror at the center of the Coronagraph Instrument’s fine-pointing system. Physik Instrumente supplied the multilayer PICMA piezoelectric actuators used in this configuration. Integrated strain-gauge sensors provide closed-loop position feedback for nanoradian-scale pointing precision. NASA previously qualified this actuator technology for Mars surface operations, where testing demonstrated more than 100 billion operating cycles without failure.
First Light Observations in the Large Magellanic Cloud
During its initial test, the Coronagraph Instrument observed a faint star in the Large Magellanic Cloud, a neighboring galaxy. The resulting image contained extra noise because engineers intentionally kept the instrument’s detectors warmer than their eventual operating temperature.
The preliminary look helps researchers refine the instrument before demanding tests begin. Meanwhile, public interest in the mission remains high following the release of initial blurry green test images from the Wide Field Instrument. In reader surveys regarding the telescope’s upcoming science goals, 57% of respondents pointed to habitable exoplanets as what they are most excited about, while 27% selected the possible source of dark energy.