Summary
NASA says the Roman Space Telescope passed fine-guidance stability tests and captured its first coronagraph images during commissioning in September 2026. The initial coronagraph observations tested focus and pointing rather than reporting a planet detection.
NASA reports that the Nancy Grace Roman Space Telescope passed tests of its fine-guidance system and, on Sept. 22, 2026, took its first observation with the Coronagraph Instrument. Follow-up work on Sept. 27 checked the instrument’s pointing. The observations mark commissioning progress: they tested whether the telescope could stay aimed steadily and produce focused images, not whether it had found a planet.
How Roman keeps its aim
Roman’s attitude control system points the observatory toward a target. Its fine-guidance system then helps hold that position during an observation, which can last from minutes to hours. To do this, the system rapidly measures guide stars—stars whose positions are known—and reports their positions to the attitude control system about four times per second. Small adjustments counter drift.
Rather than using a separate guider instrument, Roman assigns small portions of each of the 18 detectors in its Wide Field Instrument to observe guide stars. NASA says tests from Sept. 15 to 21 showed the telescope could maintain stability better than 1/100,000 of a degree for half an hour during Wide Field Instrument observations, and for as long as eight hours during Coronagraph Instrument observations. NASA compares the current pointing stability to holding a laser on a U.S. dime from about 150 miles (240 kilometres) away, and says the team aims to improve it further through tuning.
Roman is also intended to guide using patterns in the spectra it measures for science, rather than only the point-like appearance of a star. NASA said it planned to validate this spectral-guiding mode in the weeks following the tests.
First light for the coronagraph
A coronagraph is designed to block a star’s bright light so that much fainter objects, such as nearby planets and dusty disks, can be observed. Even small pointing errors or vibrations can let unwanted starlight through, making precise guidance especially important for this instrument.
After the team confirmed that the guidance system was holding the Coronagraph Instrument steady, it adjusted the instrument’s focus. On Sept. 22, the coronagraph captured a faint star in the Large Magellanic Cloud. NASA described this as a limited test that confirmed the instrument could produce a focused image. The detectors were warmer than their intended operating temperature, creating noise in the image; NASA said they were kept warmer at this stage to reduce the risk of contamination sticking to them.
For the Sept. 27 follow-up, the team cooled the detectors to improve sensitivity and observed a different location in the Large Magellanic Cloud where it expected to see many stars. NASA said the image showed stars and confirmed the telescope’s pointing.
These are early instrument checks, followed by a planned sequence of more complex tasks. The initial images demonstrate focus and pointing under test conditions; Roman’s intended planet and dusty-disk observations depend on further commissioning of the coronagraph and its associated systems.