Five Weeks Before Liftoff, a Pasadena Scientist Previews NASA’s Next Great Telescope

The Nancy Grace Roman Space Telescope is at Kennedy Space Center in Florida right now, being prepped for an August 30 launch. Five weeks before liftoff, Lee Armus will try to explain what it can do — in 30 minutes, to anyone who walks through the door.

Armus, a senior research scientist at Caltech’s IPAC, leads the Roman Science Support Center, one of three centers that will operate the telescope once it reaches its orbit about 930,000 miles from Earth. On Friday, July 24, he will give a free public lecture at the Cahill Center for Astronomy and Astrophysics in Pasadena as part of Caltech’s monthly Stargazing Lecture Series.

The talk, titled “The Roman Space Telescope: NASA’s Next Great Observatory,” is timed to a milestone: the $4.3 billion telescope is scheduled to launch on a SpaceX Falcon Heavy just over a month later, about eight months ahead of its required launch readiness date of May 2027, according to NASA.

The lecture runs from 8:00 to 8:45 p.m., followed by a panel Q&A with Caltech scientists and, weather permitting, guided stargazing with telescopes on the athletic fields adjacent to the building.

Roman is named for Nancy Grace Roman, NASA’s first chief astronomer, who was known as the “Mother of Hubble” for her role in making that telescope a reality. The new observatory that bears her name shares Hubble’s mirror diameter — 2.4 meters — but its Wide Field Instrument captures a field of view at least 100 times larger, according to NASA. Where Hubble looks deep at small patches of sky, Roman will survey enormous stretches of it.

NASA has said the telescope could measure light from a billion galaxies over its lifetime and is expected to discover tens of thousands of new exoplanets. It will also map the distribution of dark matter, investigate the mysterious force known as dark energy, and reveal how galaxies have formed and evolved over billions of years of cosmic time.

Caltech’s role in the mission runs through IPAC, the institute’s infrared data center on campus in Pasadena. IPAC’s Roman Science Support Center, which Armus leads, is responsible for operating the Coronagraph Instrument, processing spectroscopic and microlensing data, managing research proposals from the scientific community, and conducting outreach, according to IPAC. Two other centers — the Space Telescope Science Institute in Baltimore and NASA’s Goddard Space Flight Center in Maryland — share the remaining operational responsibilities.

The Stargazing Lecture Series, organized by Caltech research scientist and Director of Astrophysics Outreach Cameron Hummels, has run monthly since 2016. Each event draws community members to the Cahill Center for a 30-minute talk followed by an hour of stargazing and Q&A.

Doors open at 7:30 p.m. The event is free, open to all ages, and requires no reservations. Those unable to attend in person can watch the lecture and Q&A live-streamed on YouTube at youtube.com/live/gGVa-uOXpHY.

The Stargazing Lecture, “The Roman Space Telescope: NASA’s Next Great Observatory,” takes place on Friday, July 24, 2026. Doors open at 7:30 p.m. and the lecture begins at 8:00 p.m. Admission is free. The event is at the Cahill Center for Astronomy and Astrophysics, 1216 East California Boulevard. Parking is free in any Caltech garage or lot after 5:00 p.m. on weekdays; the closest lot is the underground garage just south of the Cahill Center. Street parking on California Boulevard requires no permit at any hour. For more information, email Cameron Hummels at chummels@caltech.edu or visit outreach.astro.caltech.edu.