NASA and SpaceX have launched NASA’s next great space observatory — the Nancy Grace Roman Space Telescope. Launched atop a Falcon Heavy from the Kennedy Space Center in Florida, Roman will travel to the Sun-Earth Lagrange Point 2, where it will use two instruments — the Wide Field Instrument and the Coronagraph Instrument — to search for exoplanets, dark energy, and other astrophysical phenomena.
Falcon Heavy and Roman lifted off at 7:26 AM EDT (11:26 UTC) from Launch Complex 39A (LC-39A) at the Kennedy Space Center in Cape Canaveral, Florida. Following launch, Roman will spend around a month cruising out to the Sun-Earth Lagrange Point 2 (L2), a time that telescope team members will use to commission the telescope and prepare it for breakthrough scientific observations.
Falcon Heavy’s two side boosters successfully returned to land at two Cape Canaveral Space Force Station landing zones. The center core was not recovered to ensure Falcon Heavy had enough performance to launch the telescope.
History of the Nancy Grace Roman Space Telescope
The concept of Roman first emerged in 2010, when the U.S. National Research Council Decadal Survey recommended that the Wide-Field Infrared Survey Telescope (WFIRST) be NASA’s top priority for the next decade of astronomy. Initially sharing similarities with the once-proposed Joint Dark Energy Mission from NASA and the Department of Energy, WFIRST’s design was studied from 2011-2012 under the name “WFIRST Design Reference Mission 1.” This first WFIRST design featured a 1.3 m three-mirror anastigmat architecture with a single-prism spectrometer instrument.
However, in 2012, the National Reconnaissance Office (NRO) offered NASA two unused Harris Corporation telescopes for the WFIRST mission. The Harris telescopes featured a mirror the same size as the joint NASA and European Space Agency (ESA) Hubble Space Telescope, but a wider field of view than Hubble’s due to the telescopes’ reduced focal length, the point at which light reflected by the mirror focuses. Although designing a completely new telescope likely would’ve been cheaper, NASA opting to use NRO telescopes for a science mission added political importance to the WFIRST mission.
After reviewing several WFIRST telescope design concepts, NASA ultimately selected one of the two Harris NRO telescopes for the WFIRST mission, with plans to implement a coronagraph instrument for the direct imaging of exoplanets.
NASA and WFIRST mission teams then spent several years planning and debating mission timelines, orbits, and goals. Throughout 2015, teams studied sending the telescope to either a geosynchronous orbit or L2, considering observing constraints, thermal stability, and the potential for future servicing missions at both locations. By February 2016, teams had decided to utilize a halo orbit at L2 for the mission.
Roman under construction at NASA’s Goddard Space Flight Center in Maryland. (Credit: NASA/Jolearra Tshiteya)
In November 2018, NASA awarded the contract for the construction and operation of the telescope to the agency’s Goddard Space Flight Center in Greenbelt, Maryland. The NASA center has extensive experience operating telescopes and deep-space missions, with the Hubble Space Telescope and the James Webb Space Telescope managed by teams at Goddard.
Members of the WFIRST team first published mission details and capabilities in a February 2019 white paper, and NASA approved the telescope for implementation and construction in March 2020. In May 2020, NASA Administrator Jim Bridenstine announced the renaming of WFIRST to the Nancy Grace Roman Space Telescope after NASA’s first female executive and Chief of Astronomy.
The telescope passed its critical design review (CDR) in 2021, clearing the way for construction to begin. While the COVID-19 pandemic led to several delays and disruptions in the telescope’s construction and launch timeline, team members set a 2027 launch date, with all flight hardware fabrication to be completed by the end of 2024.
NASA awarded the launch contract for the telescope to SpaceX’s Falcon Heavy in July 2022 for an estimated $255 million. Construction of the telescope’s bus, which houses the majority of the telescope’s instruments and electronics, was completed in September 2024, and Roman passed its spin test that October. By December 2024, Roman’s mirror and instruments had been integrated onto its bus. NASA announced that construction of the telescope was completed in November 2025.
Roman seen fully deployed at Goddard following final integration in November 2025. (Credit: NASA/Jolearra Tshiteya)
After completing final testing at Goddard, the telescope was placed in a specialized container and shipped from Maryland to the Kennedy Space Center in June 2026. Once removed from its container, Roman was moved to the Payload Hazardous Servicing Facility, where it was cleaned, inspected, fueled, and integrated onto launch hardware. The telescope was encapsulated inside its payload fairing on Aug. 24 and then moved to SpaceX’s Horizontal Integration Facility at LC-39A for integration onto Falcon Heavy.
Roman’s instruments and science goals
As mentioned, Roman, at its core, is a Harris NRO telescope retrofitted to conduct astrophysical observations. With a launch mass of 10,500 kg, the telescope features a 2.4 m-diameter three-mirror anastigmat with a focal ratio of 7.9, capable of observing wavelengths from 0.48 to 2.30 micrometers. This wavelength range will allow the telescope to observe the entire visible light and near-infrared regions of the electromagnetic spectrum. This makes Roman a sort of hybrid between Hubble and Webb: it shares Hubble’s mirror size and visible-light wavelength range, as well as Webb’s near-infrared wavelength range, though with different instruments.
The first of Roman’s two instruments is the Wide Field Instrument (WFI). This 288-megapixel camera will be capable of observing Roman’s full 0.48 to 2.30 micrometer wavelength range through one wideband and seven narrowband filters. A single image from the WFI will capture a portion of the sky larger than a full Moon and will be roughly 200 times larger than an infrared image from Hubble’s Wide Field Camera 3.
Roman’s primary mirror before integration. (Credit: NASA/Chris Gunn)
The WFI is also capable of conducting wide-field slitless spectroscopy, using a high-dispersion grism (a combination of a prism and a grating) and a low-dispersion prism. For calibration, Roman features a spectralon “dark element” that will block light from space and reflect calibration light onto the telescope’s detector. The wideband filter, seven narrowband filters, high-dispersion grism, low-dispersion prism, and dark element are all integrated onto an Element Wheel Assembly (EWA), which rotates an element into the “active” position for use during observations. The EWA will allow scientists to easily switch between imaging and spectroscopy modes on the telescope.
Even more important to the WFI is the mercury cadmium telluride-based focal-plane array (FPA), which features 18 detectors developed by Teledyne Technologies. These detectors will convert light reflected by the telescope’s mirror into electrical signals that scientists can analyze. The FPA has a 0.28-degree field of view and a resolution of 0.11 arcseconds, which can be repeatedly focused and calibrated by a set of hexapod actuators attached to the 18 detectors.
Roman is expected to conduct three main surveys with the WFI — the High-Latitude Wide-Area Survey, the High-Latitude Time-Domain Survey, and the Galactic Bulge Time-Domain Survey — comprising approximately 75% of the telescope’s five-year primary mission.
The second Roman instrument is the Coronagraph Instrument (CGI), which, by observing in a more focused 0.575 to 0.825 micrometer wavelength range, will directly image exoplanets as they orbit their host stars. The CGI, which is serving as a technology demonstrator for future coronagraph instruments and exoplanet missions, is capable of this direct imaging by severely suppressing — or “blocking” — the light from an exoplanet’s host star through dual deformable mirrors.
When Roman’s mirror reflects light from an exoplanet-hosting star system into the CGI, thousands of actuators attached to the two deformable mirrors move to change the shape of the mirrors to highlight the light from exoplanets. As the mirrors change shape, masks hide the host star, revealing the exoplanet(s) orbiting it. The changing shapes of the deformable mirrors during this process are so precise that they can compensate for errors smaller than the width of a strand of DNA, and will also be used to correct for small flaws and changes in Roman’s primary mirror over the course of its mission. Overall, the CGI is expected to reveal exoplanets as close as 0.15 arcseconds from their host stars.
Using these two instruments, Roman is expected to achieve several science goals. These goals include: researching dark matter by measuring how gravity warps light from distant galaxies through weak gravitational lensing; measuring how dark energy evolved over time by observing the shapes of galaxies and other astrophysical phenomena; discovering and monitoring exoplanets via microlensing, transits, and direct imaging; and conducting a variety of near-infrared astrophysics experiments and observations.
Roman’s launch on Falcon Heavy
SpaceX’s Falcon Heavy was contracted to launch Roman in July 2022. Falcon Heavy is a super heavy-lift launch vehicle capable of lofting payloads between 50,000 kg and 63,800 kg to low-Earth orbit depending on recovery configurations. A partially reusable launch vehicle, the two side boosters and center core are capable of landing on concrete landing pads in Florida or floating droneships downrange in the Atlantic. Falcon Heavy stands 70 m tall, with its first stage featuring 27 Merlin 1D engines (nine engines on each booster) and its second stage featuring a single Merlin 1D Vacuum engine. Both stages utilize liquid oxygen (LOX) and liquid kerosene (RP-1) propellants.
Launch occurred at 7:26 AM EDT (11:26 UTC) on Sunday, Aug. 30, from LC-39A at the Kennedy Space Center in Florida. The 45th Weather Squadron of the U.S. Space Force’s Space Launch Delta 45 initially forecasted a 50% chance of violating weather conditions for the Sunday launch window, though conditions improved to a 30% chance of violating weather conditions just hours before launch.
Booster B1072, flying for a third time, served as one of the two side boosters for this mission after previously supporting the ViaSat-3 F3 and GOES-U Falcon Heavy missions. The other side booster, B1104, was flying for the first time on this mission. Following booster engine cutoff (BECO) and separation, the boosters returned to land at the Cape Canaveral Space Force Station, with B1072 landing at Landing Zone 2 (LZ-2) and B1104 landing at Landing Zone 40 (LZ-40). The center core, which was expended, is booster B1105.
Roman during payload fairing encapsulation ahead of launch. (Credit: NASA)
After rolling out horizontally to LC-39A, Falcon Heavy — with Roman encapsulated on top — was raised to its vertical position. On launch day, the SpaceX launch director verified that Falcon Heavy is go for propellant load at T-53 minutes. SpaceX’s Falcon family of rockets uses super-chilled propellants that can quickly boil off once loaded onto the vehicle, requiring teams to load propellant within the last hour of the countdown rather than hours beforehand.
At T-50 minutes, loading of RP-1 onto the center core and boosters began, with LOX loading beginning five minutes later at T-45 minutes. At T-35 minutes, second stage RP-1 loading began. LOX loading on the second stage did not begin until T-18:30 minutes.
Falcon Heavy’s 27 first-stage engines underwent engine chill at T-7 minutes, a procedure that ensures the engines are not subjected to thermal shock at ignition. Falcon Heavy’s flight computer was commanded to begin final pre-launch checks at T-59 seconds, with the launch director giving the final “go” for launch at T-45 seconds. The rocket’s propellant tanks were fully pressurized for flight at T-20 seconds.
Finally, at T-6 seconds, the 27 Merlin 1D engines ignited, and Falcon Heavy and the Nancy Grace Roman Space Telescope lifted off from LC-39A at T0.
Falcon Heavy and Roman transit the Sun during launch on Aug. 30. (Credit: Max Evans for NSF)
Roman and Falcon Heavy experienced maximum aerodynamic pressure (MaxQ) at T+1:08 minutes. BECO occurred at T+2:24 minutes, with their separation coming three seconds later. Immediately after their separation, the boosters flipped 180 degrees and began their boostback burns to return to the Cape. Meanwhile, main engine cutoff (MECO) on the center core came at T+3:51 minutes, with stage separation three seconds later.
At T+4:15 minutes, the fairings separated, exposing Roman to the vacuum of space for the first time. The side boosters’ entry burns began at T+6:19 minutes. The boosters’ landing burns ignited at T+7:23 minutes, and the boosters landed successfully at T+7:40 minutes.
The second stage shut down its engine for the first time at T+8:28 minutes and then coasted for 16 minutes. The engine ignited for a final time at T+24:33 minutes and cut off at T+26:32 minutes. Roman was ultimately deployed from Falcon Heavy at T+31:31 minutes, beginning its multi-month journey to L2.
Immediately following deployment, Roman teams will attempt to establish communications with the telescope. Then, just a few hours later, they’ll begin deploying the telescope’s solar arrays and other supporting systems.
(Lead image: Falcon Heavy launches the Nancy Grace Roman Space Telescope on Aug. 30. Credit: Sawyer Rosenstein for NSF)
