NASA's Nancy Grace Roman Space Telescope has switched on its main science camera and captured its first starlight, confirming that the instrument survived launch and works in space. The 300-megapixel Wide Field Instrument, or WFI, recorded a field of out-of-focus stars that appear as broad, doughnut-like rings in the test image NASA released on Sept. 15.

The rings are not a problem. According to NASA's Roman mission blog, the image was taken with the detector array still stowed as it was for launch, far from best focus, and the ring-shaped features appeared as expected for that configuration. Engineers will use the image as a baseline to align the telescope's optics and tune its focus.

For the public, the milestone means the observatory remains on track. NASA expects to release Roman's first science images by early 2027, and the camera that will produce them is now confirmed operational.

Why the First Stars Look Like Doughnuts

A perfectly focused telescope squeezes a star's light into a tiny point. When the optics are far from focus, that light spreads over a wide area. In Roman's test image, each star is spread across many thousands of pixels.

The hole in the middle of each ring comes from the telescope's basic design. Like Hubble, Roman gathers light with a large primary mirror and a smaller secondary mirror mounted in front of it, which blocks the center of the incoming beam. When a star is badly out of focus, that blocked center shows up as a dark spot, producing a ring. As the team adjusts focus, those rings will shrink into crisp points.

"There is much to do, but we are on our way to groundbreaking science," said Josh Schlieder, the Wide Field Instrument scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland. The team will next activate the instrument's fine-guidance system so Roman can lock onto targets, then focus the observatory.

A Carefully Staged Power-Up

Activation followed a strict sequence. The team first let the instrument rest for 10 days with its detectors at about minus 85 degrees Fahrenheit (minus 65 Celsius) to dry out and decontaminate. On the morning of Sept. 11, engineers turned off the instrument heater and let the WFI cool to minus 225 degrees Fahrenheit (minus 143 Celsius), then activated all 18 infrared detectors, which together have a sensing area about the size of a laptop screen.

Over the following days, the team tested the calibration system, the element wheel of filters and prisms, and the focus mechanism, all of which worked as expected. Meanwhile, the detectors continued cooling toward their final operating temperature of about minus 300 degrees Fahrenheit (minus 183 Celsius).

Roman's Coronagraph Instrument, a technology demonstration designed to block starlight so faint planets can be seen, also passed an initial checkout. Operators at Caltech/IPAC in Pasadena, California, confirmed they could communicate with and control its software, thermal systems, mechanisms, cameras, and electronics. The coronagraph is now in a roughly 30-day decontamination period, according to Eric Cady of NASA's Jet Propulsion Laboratory, who leads its commissioning.

A Wider View Than Hubble for Dark Energy and Planets

Roman's 7.9-foot (2.4-meter) primary mirror matches Hubble's in size, but its camera sees far more sky at once. Each WFI image will cover a patch of sky larger than the full moon appears. According to NASA's Wide Field Instrument overview, Hubble's widest exposures are nearly 100 times smaller, and its infrared images are about 200 times smaller. Over its first five years, Roman is expected to image more than 50 times as much sky as Hubble covered in its first 30 years.

That speed serves two headline goals. The first is dark energy, the unexplained phenomenon driving the universe's accelerating expansion. By mapping enormous numbers of galaxies and distant exploding stars, Roman will help measure how that expansion has changed over time. The second is exoplanets. Roman will monitor vast numbers of stars toward the center of the Milky Way for tiny brightenings caused when a foreground star and its planets bend light from a background star, a technique called microlensing that can reveal planets missed by other methods.

The data will also serve researchers well beyond those core goals. NASA's general observer program for Roman is designed to let astronomers use the telescope for a wide range of additional studies.

Fuel for Two Decades, with Caveats

The camera news builds on a separate milestone announced the day before. Roman's first mid-course correction was so accurate, and the spacecraft launched so much lighter than budgeted, that NASA now projects fuel for at least 22 years of operations, more than double the 10-year design budget. "Roman has fuel for at least 22 years of potential science operations," Goddard Center Director Jamie Dunn said in a NASA statement on fuel savings.

That figure describes fuel capacity, not a guaranteed mission length. Part of the projected savings depends on a second course correction and orbit insertion that have not yet happened. How long Roman actually operates will also depend on the health of its hardware and on future funding decisions.

Still, extra fuel matters. At its destination, a gravitationally balanced point about 1 million miles (1.5 million kilometers) from Earth known as L2, Roman will need station-keeping burns roughly every 28 days to stay in place. When fuel runs out, science ends. More propellant means more years to extend dark energy measurements and catch rare planetary events.

What remains unknown is whether focusing and alignment will go as smoothly as activation. Commissioning often turns up minor issues that engineers must work around, and NASA has not yet released a sharp, focused image. The observatory is expected to reach its final orbit around L2 in early December, and NASA says the mission is on track for first science images by early 2027.

For readers following the mission, NASA's Roman commissioning page tracks each milestone. The bottom line: Roman's main camera works, the blurry rings are exactly what engineers expected, and the next test is turning them into sharp points of light.

What Readers Want to Know

What did NASA announce about Roman?

NASA activated Roman's Wide Field Instrument, a 300-megapixel infrared camera, and captured its first starlight. The Coronagraph Instrument also passed an initial checkout.

Why do the stars look like rings?

The camera was far from focus, with its detectors still in their launch position. Out-of-focus starlight spreads out, and the secondary mirror blocks the center of the beam, creating ring shapes that NASA said were expected.

When will Roman's first real images be released?

NASA expects to release the first science images by early 2027, after the telescope is focused and commissioning is complete.

How is Roman different from Hubble?

Roman has a primary mirror the same size as Hubble's but a far wider view. Hubble's widest exposures cover an area nearly 100 times smaller than a single Roman image.

What will Roman study?

Its main goals are measuring dark energy and finding exoplanets, especially through microlensing toward the center of the Milky Way. It will also support a wide range of other research.

How long could Roman operate?

NASA says Roman has fuel for at least 22 years, though actual mission length depends on hardware health, remaining maneuvers, and funding.