NASA’s Nancy Grace Roman Space Telescope launched successfully Sunday, lifting off from Kennedy Space Center in Florida on a SpaceX Falcon Heavy rocket at 7:26 a.m. EDT. Tucked inside it is a secondary experiment, built in part with Canadian cameras, that will test technology that could one day help answer one of humanity’s oldest questions: are we alone in the universe?
Roman’s primary mission is to study dark energy, the mysterious force that appears to be pushing the universe apart faster and faster, by surveying the sky with a field of view at least 100 times larger than the Hubble Space Telescope’s. In an odd twist, Roman’s main mirror actually started out as U.S. military hardware: a spare spy-satellite telescope, matched to Hubble’s mirror size, that intelligence officials handed over to NASA years ago because they weren’t using it.
Riding along on that same telescope, though, is something built purely to test an idea: can a spacecraft photograph a planet around another star directly, instead of just detecting it indirectly the way astronomers mostly do today? That’s the job of Roman’s Coronagraph Instrument, a technology demonstration. It works by blocking a star’s light almost perfectly with a tiny mask, revealing the far fainter planets nearby that would otherwise be lost in the glare.
If it works, the same approach is meant to fly on NASA’s next big telescope, the Habitable Worlds Observatory, a mission built specifically to search nearby stars for a planet that looks like Earth: one with water, clouds, maybe even signs of life. NASA’s science chief, Nicky Fox, called the coronagraph’s first images “the first milestone” toward that future telescope.
That’s where Canada comes in. The coronagraph relies on two cameras — ExCam, which captures the faint planet’s light, and LoCam, which watches for tiny wobbles in the star’s leftover glare and helps correct for them in real time — both built around a detector sensitive enough to register almost no light at all. Nüvü Camēras in Montreal designed the cameras, drawing on its experience building similar low-light cameras for laboratories; ABB in Quebec City then built, tested and led the project to get them ready for spaceflight. The coronagraph’s masking technique, Frederic Grandmont of ABB’s space and defense systems group told SpaceQ, comes down to erasing the star from the picture: masking it as closely as possible to its own size, so whatever tiny bit of light the planet reflects finally becomes visible.
What might that eventually look like? Grandmont points to HR 8799, a well-known multi-planet star system. Three of its four planets were the first ones astronomers ever photographed together around another star, a breakthrough made in 2008 by a Canadian-led team at the National Research Council in Victoria, B.C. “This image was the first multi-planetary exoplanet system picture, and it was a Canadian science team that did it,” Grandmont said.
Roman’s coronagraph won’t be sensitive enough on its own to say whether a planet has water or could support life; that question is left for the Habitable Worlds Observatory, still more than a decade away. What Roman can do now is prove, for the first time in real space conditions, whether the technology behind it actually works the way scientists on the ground think it does. That work starts with a roughly 90-day commissioning period, with the observatory’s first images expected before the winter holidays, Roman project manager Jackie Townsend said after the launch today.
“We think we have the technology to do what I said on Habitable World, but we haven’t validated it on a real target,” Grandmont said. “If we are as good or even better than we think we are, it’s going to be super exciting.”