Nancy Grace Roman Space Telescope

Exoplanets, Galaxies, Goddard Space Flight Center, Nancy Grace Roman Space Telescope, Stars, The Milky Way, The Universe

NASA Announces Plan to Map Milky Way With Roman Space Telescope

December 12, 2025

NASA’s Nancy Grace Roman Space Telescope team has released detailed plans for a major survey that will reveal our home galaxy, the Milky Way, in unprecedented detail. In one month of observations spread across two years, the survey will unveil tens of billions of stars and explore previously uncharted structures.

This video begins with a view of the Carina Nebula — a giant, relatively nearby star-forming region in the southern sky. Roman will view the entire nebula as well as its surroundings, including a 10,000 light-year-long swath of the spiral arm it resides in. The observation will offer an unparalleled opportunity to watch how stars grow, interact, and sculpt their environments, and it’s just one of many thousands of highlights astronomers are looking forward to from the Galactic Plane Survey NASA’s Nancy Grace Roman Space Telescope will conduct.
Credit: NASA’s Goddard Space Flight Center

“The Galactic Plane Survey will revolutionize our understanding of the Milky Way,” said Julie McEnery, Roman’s senior project scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “We’ll be able to explore the mysterious far side of our galaxy and its star-studded heart. Because of the survey’s breadth and depth, it will be a scientific mother lode.”

The Galactic Plane Survey is Roman’s first selected general astrophysics survey — one of many observation programs Roman will do in addition to its three core surveys and Coronagraph technology demonstration. At least 25% of Roman’s five-year primary mission is reserved for astronomers worldwide to propose more surveys beyond the core programs, fully leveraging Roman’s capabilities to conduct groundbreaking science. Roman is slated to launch by May 2027, but the team is on track for launch as early as fall 2026.

While ESA’s (European Space Agency’s) retired Gaia spacecraft mapped around 2 billion Milky Way stars in visible light, many parts of the galaxy remain hidden by dust. By surveying in infrared light, Roman will use powerful heat vision that can pierce this veil to see what lies beyond.

“It blows my mind that we will be able to see through the densest part of our galaxy and explore it properly for the first time,” said Rachel Street, a senior scientist at Las Cumbres Observatory in Santa Barbara, California, and a co-chair of the committee that selected the Galactic Plane Survey design.

This infographic describes the 29-day Galactic Plane Survey that will be conducted by NASA’s Nancy Grace Roman Space Telescope. The survey’s main component will cover 691 square degrees — a region of sky as large as around 3,500 full moons — in 22.5 days. Roman will also view a smaller area — 19 square degrees, the area of 95 full moons — repeatedly for about 5.5 days total to capture things that change over time. The survey’s final component will image a smattering of even smaller areas, adding up to about 4 square degrees (the area of 20 full moons) and 31 total hours, with Roman’s full suite of filters and spectroscopic tools. The survey will reveal our home galaxy in unprecedented detail including many in regions we’ve never been able to see before because they’re blocked by dust, unveiling tens of billions of stars and other objects.

Credit: NASA’s Goddard Space Flight Center

The survey will cover nearly 700 square degrees (a region of sky as large as about 3,500 full moons) along the glowing band of the Milky Way — our edge-on view of the disk-shaped structure containing most of our galaxy’s stars, gas, and dust. Scientists expect the survey to map up to 20 billion stars and detect tiny shifts in their positions with repeated high-resolution observations. And it will only take 29 days spread over the course of the mission’s first two years.

Cosmic Cradles

Stars are born from parent clouds of gas and dust. Roman will peer through the haze of these nesting grounds to see millions of stellar embryos, newborn stars still swaddled in shrouds of dust, tantrumming toddler stars that flare unpredictably, and young stars that may have planetary systems forming around them. Astronomers will study stellar birth rates across a wide range of masses and stitch together videos that show how stars change over time.

“This survey will study such a huge number of stars in so many different stellar environments that we’ll be sampling every phase of a star’s evolution,” Street said.

Observing so many stars in various stages of early development will shed light on the forces that shape them. Star formation is like a four way tug-of-war between gravity, radiation, magnetism, and turbulence. Roman will help us study how these forces influence whether gas clouds collapse into full-fledged stars, smaller brown dwarfs — in-between objects that are much heavier than planets but not massive enough to ignite like stars — or new worlds.

The Galactic Plane Survey by NASA’s Nancy Grace Roman Space Telescope will scan the densest part of our galaxy, where most of its stars, gas, and dust reside — the most difficult region to study from our place inside the Milky Way since we have to look through so much light-blocking material. Roman’s wide field of view, crisp resolution, and infrared vision will help astronomers peer through thick bands of dust to chart new galactic territory.
Credit: NASA’s Goddard Space Flight Center

Some stars are born in enormous litters called clusters. Roman will study nearly 2,000 young, loosely bound open clusters to see how the galaxy’s spiral arms trigger star formation. The survey will also map dozens of ancient, densely packed globular clusters near the center of the galaxy that could help astronomers reconstruct the Milky Way’s early history.

Comparing Roman’s snapshots of clusters scattered throughout the galaxy will enable scientists to study nature versus nurture on a cosmic scale. Because a cluster’s stars generally share the same age, origin, and chemical makeup, analyzing them allows astronomers to isolate environmental effects very precisely.

Pulse Check

When they run out of fuel, Sun-like stars leave behind cores called white dwarfs and heavier stars collapse to form neutron stars and black holes. Roman will find these stellar embers even when they’re alone thanks to wrinkles in space-time.

Anything that has mass warps the underlying fabric of the universe. When light from a background star passes through the gravitational well around an intervening object on its journey toward Earth, its path slightly curves around the object. This phenomenon, called microlensing, can temporarily brighten the star. By studying these signals, astronomers can learn the mass and size of otherwise invisible foreground objects.

A separate survey — Roman’s Galactic Bulge Time-Domain Survey — will conduct deep microlensing observations over a smaller area in the heart of the Milky Way. The Galactic Plane Survey will conduct repeated observations over a shorter interval but across the whole center of the galaxy, giving us the first complete view of this complex galactic environment. An unobscured view of the galaxy’s central bar will help astronomers answer the question of its origin, and Roman’s videos of stars in this region will enable us to study some ultratight binary objects at the very ends of their lives thanks to their interactions with close companions.

“Compact binaries are particularly interesting because they’re precursors to gravitational-wave sources,” said Robert Benjamin, a visiting professor at the University of Wisconsin-Whitewater, and a co-chair of the committee that selected the Galactic Plane Survey design. When neutron stars and black holes merge, the collision is so powerful that it sends ripples through the fabric of space-time. “Scientists want to know more about the pathways that lead to those mergers.”

optical

infrared

This colorful image, taken by the Hubble Space Telescope and published in 2018, celebrated the observatory’s 28th anniversary of viewing the heavens.

This colorful image, taken by the Hubble Space Telescope and published in 2018, celebrated the observatory’s 28th anniversary of viewing the heavens.

optical

infrared

Optical vs infrared

Two Views

Roman’s repeated observations will also monitor stars that flicker. Ground-based surveys detect thousands of bright stellar outbursts, but often can’t see the faint, dust-obscured stars that produce them. Roman will pinpoint the culprits plus take high-resolution snapshots of the aftermath.

Some stars throb rhythmically, and the speed of their pulsing is directly linked to their intrinsic brightness. By comparing their true brightness to how bright they appear from Earth, astronomers can measure distances across the galaxy. Roman will find these blinking stars farther away than ever before and track them over time, helping astronomers improve their cosmic measuring sticks.

“Pairing Roman’s Galactic Plane Survey with other Milky Way observations will create the best portrait of the galaxy we’ve ever had,” Benjamin said.

Download additional images and video from NASA’s Scientific Visualization Studio.

For more information about the Roman Space Telescope, visit:

https://www.nasa.gov/roman

By Ashley Balzer
NASA’s Goddard Space Flight Center, Greenbelt, Md.

Media contact:

Claire Andreoli
NASA’s Goddard Space Flight Center, Greenbelt, Md.
301-286-1940

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Dec 12, 2025

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Ashley Balzer

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NASA’s Nancy Grace Roman Space Telescope Completed

December 5, 2025

Two people in white jumpsuits look up at a large telescope with three black and orange panels facing them. They are in a large white cleanroom with equipment and scaffolding.

Over the course of several hours, technicians meticulously connected the inner and outer segments of NASA’s Nancy Grace Roman Space Telescope.

NASA/Jolearra Tshiteya

Two technicians look up at NASA’s Nancy Grace Roman Space Telescope after its inner and outer segments were connected at the agency’s Goddard Space Flight Center in Greenbelt, Maryland on Nov. 25, 2025. This marked the end of Roman’s construction. After final testing, the telescope will move to the launch site at NASA’s Kennedy Space Center in Florida for launch preparations in summer 2026. Roman — named after Dr. Nancy Grace Roman, NASA’s first chief astronomer — is slated to launch by May 2027, but the team is on track for launch as early as fall 2026.

See more photos of the completed observatory.

Image credit: NASA/Jolearra Tshiteya

Source Link NASA’s Nancy Grace Roman Space Telescope Completed

Dark Energy, Dark Matter, Exoplanets, Goddard Space Flight Center, Nancy Grace Roman Space Telescope, Stars, The Universe

NASA Completes Nancy Grace Roman Space Telescope Construction

December 4, 2025

NASA’s next big eye on the cosmos is now fully assembled. On Nov. 25, technicians joined the inner and outer portions of the Nancy Grace Roman Space Telescope in the largest clean room at the agency’s Goddard Space Flight Center in Greenbelt, Maryland.

The complete observatory in a clean room

NASA’s Nancy Grace Roman Space Telescope is now fully assembled following the integration of its two major segments on Nov. 25 at the agency’s Goddard Space Flight Center in Greenbelt, Md. The mission is slated to launch by May 2027, but the team is on track for launch as early as fall 2026.

Credit: NASA/Jolearra Tshiteya

“Completing the Roman observatory brings us to a defining moment for the agency,” said NASA Associate Administrator Amit Kshatriya. “Transformative science depends on disciplined engineering, and this team has delivered—piece by piece, test by test—an observatory that will expand our understanding of the universe. As Roman moves into its final stage of testing following integration, we are focused on executing with precision and preparing for a successful launch on behalf of the global scientific community.”

After final testing, Roman will move to the launch site at NASA’s Kennedy Space Center in Florida for launch preparations in summer 2026. Roman is slated to launch by May 2027, but the team is on track for launch as early as fall 2026. A SpaceX Falcon Heavy rocket will send the observatory to its final destination a million miles from Earth.

“With Roman’s construction complete, we are poised at the brink of unfathomable scientific discovery,” said Julie McEnery, Roman’s senior project scientist at NASA Goddard. “In the mission’s first five years, it’s expected to unveil more than 100,000 distant worlds, hundreds of millions of stars, and billions of galaxies. We stand to learn a tremendous amount of new information about the universe very rapidly after Roman launches.”

An infographic tallying up several things Roman will observe

NASA’s Nancy Grace Roman Space Telescope will survey vast swaths of sky during its five-year primary mission. During that time, scientists expect it to see an incredible number of new objects, including stars, galaxies, black holes and planets outside our solar system, known as exoplanets. This infographic previews some of the discoveries scientists anticipate from Roman’s data deluge.

Credit: NASA’s Goddard Space Flight Center

Observing from space will make Roman very sensitive to infrared light — light with a longer wavelength than our eyes can see — from far across the cosmos. Pairing its crisp infrared vision with a sweeping view of space will allow astronomers to explore myriad cosmic topics, from dark matter and dark energy to distant worlds and solitary black holes, and conduct research that would take hundreds of years using other telescopes.

“Within our lifetimes, a great mystery has arisen about the cosmos: why the expansion of the universe seems to be accelerating. There is something fundamental about space and time we don’t yet understand, and Roman was built to discover what it is,” said Nicky Fox, associate administrator, Science Mission Directorate, NASA Headquarters in Washington. “With Roman now standing as a complete observatory, which keeps the mission on track for a potentially early launch, we are a major step closer to understanding the universe as never before. I couldn’t be prouder of the teams that have gotten us to this point.”

Double vision

Roman is equipped with two instruments: the Wide Field Instrument and the Coronagraph Instrument technology demonstration.

The coronagraph will demonstrate new technologies for directly imaging planets around other stars. It will block the glare from distant stars and make it easier for scientists to see the faint light from planets in orbit around them. The Coronagraph aims to photograph worlds and dusty disks around nearby stars in visible light to help us see giant worlds that are older, colder, and in closer orbits than the hot, young super-Jupiters direct imaging has mainly revealed so far.

“The question of ‘Are we alone?’ is a big one, and it’s an equally big task to build tools that can help us answer it,” said Feng Zhao, the Roman Coronagraph Instrument manager at NASA’s Jet Propulsion Laboratory in Southern California. “The Roman Coronagraph is going to bring us one step closer to that goal. It’s incredible that we have the opportunity to test this hardware in space on such a powerful observatory as Roman.”

The coronagraph team will conduct a series of pre-planned observations for three months spread across the mission’s first year-and-a-half of operations, after which the mission may conduct additional observations based on scientific community input.

The Wide Field Instrument is a 288-megapixel camera that will unveil the cosmos all the way from our solar system to near the edge of the observable universe. Using this instrument, each Roman image will capture a patch of the sky bigger than the apparent size of a full moon. The mission will gather data hundreds of times faster than NASA’s Hubble Space Telescope, adding up to 20,000 terabytes (20 petabytes) over the course of its five-year primary mission.

“The sheer volume of the data Roman will return is mind-boggling and key to a host of exciting investigations,” said Dominic Benford, Roman’s program scientist at NASA Headquarters.

Over the course of several hours, technicians meticulously connected the inner and outer segments of NASA’s Nancy Grace Roman Space Telescope, as shown in this time-lapse. Next, Roman will undergo final testing prior to moving to the launch site at NASA’s Kennedy Space Center in Florida for launch preparations in summer 2026.

NASA/Sophia Roberts

Survey trifecta

Using the Wide Field Instrument, Roman will conduct three core surveys which will account for 75% of the primary mission. The High-Latitude Wide-Area Survey will combine the powers of imaging and spectroscopy to unveil more than a billion galaxies strewn across a wide swath of space and time. Astronomers will trace the evolution of the universe to probe dark matter — invisible matter detectable only by how its gravity affects things we can see — and trace the formation of galaxies and galaxy clusters over time.

The High-Latitude Time-Domain Survey will probe our dynamic universe by observing the same region of the cosmos repeatedly. Stitching these observations together to create movies will allow scientists to study how celestial objects and phenomena change over time periods of days to years. That will help astronomers study dark energy — the mysterious cosmic pressure thought to accelerate the universe’s expansion — and could even uncover entirely new phenomena that we don’t yet know to look for.

Roman’s Galactic Bulge Time-Domain Survey will look inward to provide one of the deepest views ever of the heart of our Milky Way galaxy. Astronomers will watch hundreds of millions of stars in search of microlensing signals — gravitational boosts of a background star’s light caused by the gravity of an intervening object. While astronomers have mainly discovered star-hugging worlds, Roman’s microlensing observations can find planets in the habitable zone of their star and farther out, including worlds like every planet in our solar system except Mercury. Microlensing will also reveal rogue planets—worlds that roam the galaxy untethered to a star — and isolated black holes. The same dataset will reveal 100,000 worlds that transit, or pass in front of, their host stars.

The remaining 25% of Roman’s five-year primary mission will be dedicated to other observations that will be determined with input from the broader scientific community. The first such program, called the Galactic Plane Survey, has already been selected.

Because Roman’s observations will enable such a wide range of science, the mission will have a General Investigator Program designed to support astronomers to reveal scientific discoveries using Roman data. As part of NASA’s commitment to Gold Standard Science, NASA will make all of Roman’s data publicly available with no exclusive use period. This ensures multiple scientists and teams can use data at the same time, which is important since every Roman observation will address a wealth of science cases.

NASA’s freshly assembled Nancy Grace Roman Space Telescope will revolutionize our understanding of the universe with its deep, crisp, sweeping infrared views of space. The mission will transform virtually every branch of astronomy and bring us closer to understanding the mysteries of dark energy, dark matter, and how common planets like Earth are throughout our galaxy. Roman is on track for launch by May 2027, with teams working toward a launch as early as fall 2026. Credit: NASA’s Goddard Space Flight Center

Roman’s namesake — Dr. Nancy Grace Roman, NASA’s first chief astronomer — made it her personal mission to make cosmic vistas readily accessible to all by paving the way for telescopes based in space.

“The mission will acquire enormous quantities of astronomical imagery that will permit scientists to make groundbreaking discoveries for decades to come, honoring Dr. Roman’s legacy in promoting scientific tools for the broader community,” said Jackie Townsend, Roman’s deputy project manager at NASA Goddard. “I like to think Dr. Roman would be extremely proud of her namesake telescope and thrilled to see what mysteries it will uncover in the coming years.”

The Nancy Grace Roman Space Telescope is managed at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, with participation by NASA’s Jet Propulsion Laboratory in Southern California; Caltech/IPAC in Pasadena, California; the Space Telescope Science Institute in Baltimore; and a science team comprising scientists from various research institutions. The primary industrial partners are BAE Systems Inc. in Boulder, Colorado; L3Harris Technologies in Rochester, New York; and Teledyne Scientific & Imaging in Thousand Oaks, California.

To learn about the Roman Space Telescope, visit:

https://www.nasa.gov/roman

By Ashley Balzer
NASA’s Goddard Space Flight Center, Greenbelt, Md.

Media contact:

Claire Andreoli
NASA’s Goddard Space Flight Center, Greenbelt, Md.
301-286-1940

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Dec 04, 2025

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Ashley Balzer

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Ashley Balzer

ashley.m.balzer@nasa.gov

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NASA’s Roman Observatory Passes Spate of Key Tests

November 25, 2025

NASA’s nearly complete Nancy Grace Roman Space Telescope has made another set of critical strides toward launch. This fall, the outer portion passed two tests — a shake test and an intense sound blast — to ensure its successful launch. The inner portion of the observatory underwent a major 65-day thermal vacuum test, showing that it will function properly in space. As NASA’s next flagship space telescope, Roman will address essential questions in the areas of dark energy, planets outside our solar system, and astrophysics.

Core portion of Roman observatory exiting test chamber

The inner portion of NASA’s Nancy Grace Roman Space Telescope (which consists of the telescope, instrument carrier, two instruments, and spacecraft) recently passed thermal vacuum testing. In this photo, the assembly is being lifted out of the Space Environment Simulator after completing 65 days of assessments.

Credit: NASA/Jolearra Tshiteya

“We want to make sure Roman will withstand our harshest environments,” said Rebecca Espina, a deputy test director at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “From a mechanical standpoint, our heaviest loads and stresses come from launch, so we use testing to mimic the launch environment.”

The vibration and acoustic testing were the final round of launch simulations for the outer portion of the Roman observatory, which consists of the outer barrel assembly, deployable aperture cover, and recently installed flight solar panels.

During acoustic testing, a large chamber with gigantic horns emulated the launch’s thunderous sounds, which cause high-frequency vibrations. Test operators outfitted the chamber and assembly with various sensors to monitor the hardware’s response to the sound, which gradually ramped up to a full minute at 138 decibels — louder than a jet plane’s takeoff at close range!

After moving to a massive shaker table, Roman’s outer assembly went through testing to replicate the rocket launch’s lower-frequency vibrations. Each individual test lasts only about a minute, sweeping from 5 to 50 hertz (the lowest note on a grand piano vibrates at 27.5 hertz), but NASA engineers tested three axes of movement over several weeks, breaking up the tests with on-the-spot data analysis.

Like in acoustic testing, the team installed sensors to capture the assembly’s response to the shaking. Structural analysts and test operators use this information not only to evaluate success but also to improve models and subsequent assessments.

“There’s a real sense of accomplishment when you get a piece of hardware this large through this test program,” said Shelly Conkey, lead structural analyst for this assembly at NASA Goddard. “I am proud of the work that our team of people has done.”

The outer portion of the Roman observatory stands in the acoustic testing chamber

The outer portion of NASA’s Nancy Grace Roman Space Telescope (which consists of the outer barrel assembly, deployable aperture cover, and solar panels) recently passed vibration and acoustic testing. The structure is shown here in the acoustic testing chamber at NASA’s Goddard Space Flight Center in Greenbelt, Md., where it was blasted with intense sound to simulate launch conditions.

Credit: NASA/Jolearra Tshiteya

The core portion of the observatory (the telescope, instrument carrier, two instruments, and spacecraft bus) moved into the Space Environment Simulator test chamber at NASA Goddard in August. There, it was subjected to extreme temperatures to mimic the chill of space and heat from the Sun. A team of more than 200 people ran simulations continuously for more than two months straight, assessing the telescope’s optics and the assembly’s overall mission readiness.

“The thermal vacuum test marked the first time the telescope and instruments were used together,” said Dominic Benford, Roman’s program scientist at NASA Headquarters in Washington. “The next time we turn everything on will be when the observatory is in space!”

Gif of the inner portion of the observatory exiting thermal vacuum testing

Following extensive assessments, the core portion of NASA’s Nancy Grace Roman Space Telescope was removed from the test chamber (as shown in this gif) and returned to the largest clean room at NASA’s Goddard Space Flight Center in Greenbelt, Md. Next, it will be prepped for final integration.

Credit: NASA/Sophia Roberts

The team expects to connect Roman’s two major parts in November, resulting in a complete observatory by the end of the year. Following final tests, Roman will move to the launch site at NASA’s Kennedy Space Center in Florida for launch preparations in summer 2026. Roman remains on schedule for launch by May 2027, with the team aiming for as early as fall 2026.

For more information about the Roman Space Telescope, visit:

https://www.nasa.gov/roman

By Laine Havens and Ashley Balzer
NASA’s Goddard Space Flight Center, Greenbelt, Md.

Media contact:

Claire Andreoli
NASA’s Goddard Space Flight Center, Greenbelt, Md.
301-286-1940

Details

Last Updated

Nov 25, 2025

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Ashley Balzer

Contact

Ashley Balzer

ashley.m.balzer@nasa.gov

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Goddard Space Flight Center

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