NASA's Roman Telescope Clears Its Checkout and Starts the Last Tests Before Surveys

NASA's Nancy Grace Roman Space Telescope has completed the checkout of the observatory and its main instrument and has entered science commissioning, the agency said Oct. 22, 2026.

Science commissioning is the last phase before the telescope begins its sky surveys. NASA's mission blog said the team is now making planned test observations to measure how the observatory performs, calibrate how the instruments respond to light and refine image quality before science operations start.

"We've established that the observatory is fully functional," said Julie McEnery, Roman's senior project scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "The telescope can guide and take exposures, data flows appropriately, and we can slew from one place to another for observations."

NASA said scientists had expected two kinds of target to give the telescope trouble: sky crowded with stars and nebulae shrouded in thick dust. Roman aims by holding steady on individual stars in the direction it needs to point. Tom Barclay, Roman's operations project scientist at Goddard, said the team had worried that in those regions the fine guidance system "might get confused or have trouble staying tethered to those stars," and that test observations "have shown that Roman performs wonderfully in all cases."

Josh Schlieder, the mission's Wide Field Instrument scientist at Goddard, said even subtle flaws "could mask the small signals we are aiming to measure." He said that in a typical observation Roman will see "objects that are a hundred million times fainter than the human eye can detect."

The milestone follows NASA's report of Oct. 14, 2026, that the team had checked out the Wide Field Instrument, Roman's main camera, and sharpened the telescope's focus.

NASA also said some of the observatory's systems are performing better than the mission requires, which could open up new scientific capabilities.