Roman Space Telescope Headed to Deep Space

NASA’s Nancy Grace Roman Space Telescope is on its way to deep space. Launched aboard a SpaceX Falcon Heavy rocket, the observatory will shed new light on the mystery of dark energy, observe distant exoplanets, and explore the structure of the universe.

Falcon Heavy lifted off at 7:26 AM EDT from Launch Complex 39A at Kennedy Space Center in Florida, rising into a picturesque morning sky. The rocket’s twin side boosters separated two and a half minutes into flight and returned to the coast for their signature double landing, while the spacecraft itself continued into orbit aboard the core and upper stage.

After separating from Falcon’s upper stage, the Roman Space Telescope deployed its solar arrays and sunshade and made its first contact with Earth. Roman is now settling in for the long coast to the Earth-Sun L2 point, beginning a three-month commissioning period before the telescope is fully operational.

“We let the detectors cool down to their operating temperature, then we start turning on the system,” says Jason Hylan, the Observatory Manager for the Roman Space Telescope. “It’s kind of like turning on a custom-made computer with a custom-made operating system, so you’ve got to go put it through the paces.”

Once fully online, Roman will downlink about 1.4 terabytes of data per day—nearly 30 times that of the James Webb Space Telescope. When not in contact with Earth, either due to disruptions like weather or because the scope is pointing at a target, the spacecraft can store up to 10 TB in an onboard backlog, says Hylan.

Much of that data will contain new observations of exoplanets, worlds orbiting other stars. To date, most exoplanets have been studied indirectly, such as by watching for the wobbling or dimming of their parent stars. But Roman’s coronagraph instrument will help block and filter the light of these stars, enabling Roman to look at the planets themselves.

“What’s different here is that we can see the planet, and because we can see it we can get the spectrum,” says Dr. Bertrand Mennesson, Roman’s Deputy Project Scientist. “And if we can get the spectrum of the planet, we can tell exactly what its atmosphere is made of.”

Future telescopes, such as NASA’s Habitable Worlds Observatory, could use even more effective coronagraphs to view planets as small and faint as the Earth around other stars.

That technology is “much closer than people think,” says Dr. Mennesson, and useful for a wide range of observatories. “I think that the new norm could be that, from now on, every large telescope that we launch in the optical [range] will have a coronagraph.”

The telescope’s wide angle also allows it to view large portions of the sky at once, a crucial ability for its main science surveys. While other observatories are designed for detailed views of smaller targets, Roman can track targets like supernovae all throughout the galaxy, creating a better “map” of how the universe is expanding.

Astrophysicist Dr. Adam Riess is one of the leading experts in this field; in 2011, he and two other researchers discovered that the universe’s expansion was accelerating, a mystery Roman aims to help solve. That work was achieved by tracking supernovae—slow going with the older Hubble space telescope.

“We would take like 10 photos to find a supernova,” says Riess. “Now, every single photo that Roman takes will have dozens and dozens of supernovae in them, and of course we’ll take many. So basically we’re going to greatly increase the amount of supernovae we have, which will give us a more precise picture of the recent expansion history.”

Roman’s mission is off to a smooth start, and within the next few months it will begin seeking answers to some of astronomers’ and astrophysicists’ most pressing questions. But Hylan expects that Roman, like Hubble and Webb before it, will uncover secrets of the universe far beyond NASA’s predictions.

“We’re explorers, as humans, and discovering new things—things that you didn’t think of—that excites me the most.”