NASA switched on a 300-megapixel camera now a million miles from Earth

NASA has powered up the Wide Field Instrument on the Nancy Grace Roman Space Telescope, a 300-megapixel infrared camera, while the observatory is roughly one million miles from Earth and still coasting toward its working position. The switch-on happened on September 11, and the agency confirmed it in a mission blog post four days later.

The camera is the main instrument on a telescope launched on August 30 aboard a SpaceX Falcon Heavy. Its first science images are scheduled for early 2027, which makes this month’s checkout the first proof that the hardware survived the trip and works as built.

The Wide Field Instrument in numbers

Roman is named for Nancy Grace Roman, NASA’s first chief astronomer, often called the mother of the Hubble Space Telescope, and it is meant to take on three jobs: measuring dark energy, taking a census of planets across the galaxy, and surveying infrared sources that visible-light telescopes miss. The Wide Field Instrument carries most of that load, which is why its power-up is the single most important checkpoint before the observatory settles into its orbit.

NASA’s post on activating Roman’s primary instrument describes a camera built around 18 infrared detectors whose combined light-sensitive area is about the size of a laptop screen. A single exposure takes in a patch of sky wider than the full Moon while keeping the fine detail that made Hubble famous. The mission overview puts the field of view at least 100 times larger than Hubble’s, which is why the project expects to measure light from as many as a billion galaxies over its lifetime.

The detectors only work cold. Engineers let the instrument cool in space, then brought the focal plane down to its operating temperature of about minus 300 degrees Fahrenheit, or minus 183 degrees Celsius, before applying power. Space.com’s account adds that the detectors were switched on on September 11 after the instrument chilled from minus 85 to minus 225 degrees Fahrenheit, and that by September 13 the focus components had been verified and the first starlight photons collected, as out-of-focus test images of stars.

Schlieder and the Goddard team

Josh Schlieder, the Wide Field Instrument scientist at NASA’s Goddard Space Flight Center, carried the announcement. After years of effort to build and test the instrument on the ground, Schlieder said in the agency’s post, the team finally has confirmation that it is operational in space. He also called the activation a huge milestone for the team at Goddard, for the industry teams at BAE Systems and Teledyne that helped build the camera and its detectors, and for the mission’s science centers.

The checkout went beyond the detectors, and it moved quickly. Over September 11 and 12 the team exercised the instrument’s calibration system and the pathway that carries data to the ground, which are the pieces that decide whether a 300-megapixel stream can reach scientists intact. A camera of this size produces far more data per exposure than most space instruments, so the link from detector to downlink is as much a part of the test as the detectors themselves, and both passed their first checks within a day of power-on.

A million miles out and still travelling

Counting from the August 30 launch, the camera was switched on twelve days into the flight, well before the observatory reached its destination.

Roman is headed for the second Sun-Earth Lagrange point, L2, on the far side of Earth from the Sun. ScienceDaily’s version of the NASA release gives the distance as roughly one million miles, and space.com says arrival is expected about 12 weeks after launch. Because the spacecraft is still moving outward, the figure is a snapshot: a Tech Times report dated September 30 puts it nearer 930,000 miles, or 1.5 million kilometres.

The camera is not the only instrument waking up. The Coronagraph Instrument, run from Caltech’s IPAC in Pasadena, finished its own early checkout and entered a 30-day decontamination period, and Tech Times reports that it captured real starlight on September 22 and again on September 27. Goddard’s Begoña Vila said the observatory held stable to better than one hundred-thousandth of a degree during those tests, and JPL’s Vanessa Bailey said the observation confirmed that the instrument can produce a focused image.

The Wide Field Instrument has not yet begun its primary survey work. NASA’s schedule holds the first science images to early 2027, after the telescope reaches L2 and the remaining calibration is finished. Space.com reports that the observatory carries enough propellant for 22 years of operations, so the commissioning schedule is not racing a fuel clock. Schlieder’s group still has to turn the out-of-focus test frames into the sharp, wide mosaics the mission was designed to deliver.

This article was produced with the assistance of AI and reviewed by Morning Overview editors prior to publication.

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