The Nancy Grace Roman Space Telescope is ready to launch

**Sarah Al-Ahmed** (0:05)
We're looking forward to the launch of the Nancy Grace Roman Space Telescope, this week on Planetary Radio.
I'm Sarah Al-Ahmed of the Planetary Society, with more of the human adventure across our solar system and beyond. And boy, do we have an adventure this week. The launch of the most powerful survey telescope ever built is just days away. Today, we're talking about the Nancy Grace Roman Space Telescope, with two of the scientists leading the mission. Jason Rhodes, the Roman Project Scientist at NASA's Jet Propulsion Laboratory, and Julie McEnery, the Senior Project Scientist at NASA's Goddard Space Flight Center. Then Bruce Betts, our Chief Scientist at the Planetary Society, joins me for What's Up. We'll talk about the technology that could one day help us find Earth-like worlds around other stars, coronagraphs.
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After more than two decades of planning, building and testing, the Nancy Grace Roman Space Telescope is sitting on the pad at the Kennedy Space Center, ready to fly. The current launch date is August 30th, when a SpaceX Falcon Heavy is going to send it on a 100-day journey to its new home, about a million miles from Earth at the Sun-Earth Lagrange Point 2 Once it completes its commissioning and turns its instruments on the sky, it's going to show us the universe in a way that no telescope ever has. And over its mission, it's expected to discover thousands of new worlds, radically expanding our census of exoplanets. I sat down with two of the mission's project scientists to talk about what's coming. Dr. Julie McEnery is the Senior Project Scientist at NASA's Goddard Space Flight Center, which leads the Roman mission. Before Roman, she spent years as the Project Scientist for the Fermi Gamma-ray Space Telescope, studying some of the most energetic and violent events in the universe. I'm talking blazars, gamma-ray bursts, and merging neutron stars. Her background in high-energy astrophysics gives her a different perspective on a mission whose headline science is the slow, quiet work of mapping dark energy and dark matter. We're also joined by Dr. Jason Rhodes, who's the Roman Project Scientist at NASA's Jet Propulsion Laboratory. He's a cosmologist who helped pioneer a technique called weak gravitational lensing. Among other things, it's a way of mapping the invisible dark matter that holds the universe together by measuring how gravity subtly distorts the light from distant galaxies. He's been working on this mission since about 2002, back when it was still called the Supernova Acceleration Probe, and then later WFIRST. He's also worked on the European Space Agency's Euclid mission, and he's deeply involved in the Vera Rubin Observatory, making him one of the key people connecting all three of the major survey missions now coming online.
Hey, Jason and Julie, thanks for joining me.

**Jason Rhodes** (3:18)
Thanks for having us.

**Sarah Al-Ahmed** (3:20)
Before we talk about this telescope, which I am wildly excited for, I think the entire space community has been waiting for this for so long. But I want to talk a little bit about the person who it was named for.
Julie, who was Nancy Grace Roman?

**Julie McEnery** (3:35)
Nancy Grace Roman was NASA's first chief astronomer. She is the person who had the vision for space-based astrophysics. She's sometimes called the mother of Hubble, but I actually think she's the mother, or at least the instigator of an entire range of space-based astrophysics. I think it is not an exaggeration to say that without her, we might not be here today having this conversation.
She was explicitly interested in coronography. I think she would have been delighted that Roman includes an instrument that is going to test and debut new technologies in space to be able to image planets around other stars. She understood the technical details. She understood the engineering. She understood the project management. So she was, you know, she understood the science. And I think it was a combination of having all of those skills that allowed her to really push things forward.

**Sarah Al-Ahmed** (4:33)
Jason, how did you get involved in the mission? And what's kept you on it for so many years?

**Jason Rhodes** (4:38)
Well soon after the accelerating expansion of the universe was discovered in the late 90s, a group of people at the Department of Energy started planning a space mission to study supernova. And they called it the Supernova Acceleration Probe. And in about 2002, they realized there was more they could do with this space mission, including using a technique called weak gravitational lensing, which is a technique that I helped pioneer back then. So they invited me on to their mission, SNAP, as they called it. And SNAP became a concept for a NASA-DOE Joint Dark Energy Mission in the early 2000s.