\n\t\t\t\t\t\t\t\tNASA\u2019s Roman Space Telescope Primary Mirror Gets Last Look\t\t\t\t\t\t\t<\/h1>\n<\/p><\/div>\n<\/p><\/div>\n<\/div>\n<\/div>\n![\"Wide](\"https:\/\/www.nasa.gov\/wp-content\/uploads\/2026\/05\/mirror01.jpg?w=1536\")
<\/figure>\n<\/p><\/div>\n<\/p><\/div>\n<\/p><\/div>\n\n\n\nThis photo peers down the barrel of the Roman telescope with its visor-like sunshade deployed.<\/figcaption><\/div>\n<\/p><\/div>\n\n\t\t\t\t\t\tCredits: <\/span>
\n\t\t\t\t\t\tNASA\/Sydney Rohde<\/span>\n\t\t\t\t\t<\/div>\n<\/figcaption><\/div>\n<\/p><\/div>\n<\/p><\/div>\nEngineers at NASA\u2019s Goddard Space Flight Center in Greenbelt, Maryland, have completed their final inspection of a key element for the agency\u2019s Nancy Grace Roman Space Telescope: the primary mirror. This 7.9-foot (2.4-meter) mirror will collect and focus light from cosmic objects near and far, helping Roman capture stunning panoramas of space.<\/p>\n\n\n<\/div>The primary mirror for NASA\u2019s Nancy Grace Roman Space Telescope has passed its final inspection. On May 20 and 21, engineers at NASA\u2019s Goddard Space Flight Center in Greenbelt, Md., confirmed that no specks fell onto the mirrors during testing and that there are no defects in the coating or alignment. With this milestone complete, the primary mirror is ready for its next view: space.
NASA\u2019s Goddard Space Flight Center<\/figcaption><\/figure>\n\u201cThe Roman engineering team laid eyes on the telescope for the final time before it, in turn, becomes the eyes of humanity, revealing the wonders of the cosmos,\u201d said J. Scott Smith, the Roman telescope manager at NASA Goddard. \u201cIt is a profoundly humbling moment to witness the culmination of hard work from so many dedicated individuals, teams, and partner organizations, including L3Harris.\u201d<\/p>\n
On May 20, engineers turned the Roman observatory onto its side and deployed the \u201chood<\/a>\u201d that will be stowed for launch to protect the mirror. Then the team conducted a meticulous visual inspection to ensure no specks fell onto the mirrors during testing and confirm there are no defects in the coating or alignment.<\/p>\n\u201cWe developed a method of using a high-resolution camera equipped with a very powerful zoom lens to do a multi-purpose inspection,\u201d said Bente Eegholm<\/a>, optics lead for Roman\u2019s Optical Telescope Assembly at NASA Goddard. \u201cThe mirror passed with flying colors, keeping the mission on track for an early September launch.\u201d<\/p>\n\n\n\n![\"Photo](\"https:\/\/www.nasa.gov\/wp-content\/uploads\/2026\/05\/mirror03.jpg?w=1365\")
<\/a><\/figure>\nTechnicians stow Roman\u2019s deployable aperture cover, a large sunshade designed to keep unwanted light out of the telescope.<\/div>\nNASA\/Sydney Rohde <\/div>\n<\/figcaption><\/div>\n<\/div>\n<\/div>\nThe team carefully observed the optics along the path light will follow to the Wide Field Instrument<\/a> detector array and confirmed it remains in proper alignment following the observatory shake test<\/a>.<\/p>\n\u201cIn order to gather very sensitive measurements of objects strewn throughout space, all of Roman\u2019s components have to be ultraprecise,\u201d Eegholm said. \u201cThe primary mirror certainly delivers on that precision.\u201d<\/p>\n
Roman\u2019s primary mirror sports a layer of silver less than 400 nanometers thick \u2014 about 200 times thinner than a human hair. The silver coating was specifically chosen for Roman because of how well it reflects near-infrared light. By contrast, the Hubble Space Telescope\u2019s mirror<\/a> is coated with layers of aluminum and magnesium fluoride to optimize visible and ultraviolet light reflectivity. Likewise, the James Webb Space Telescope\u2019s mirrors<\/a> have a gold coating to suit its longer wavelength infrared observations.<\/p>\nThe Roman mirror is so finely polished that the average bump on its surface is only 1.2 nanometers tall \u2014 more than twice as smooth as the mission requires. If the mirror were scaled up to Earth\u2019s size, these bumps would be just a quarter of an inch high.<\/p>\n
\n\n\n![\"Close-up](\"https:\/\/www.nasa.gov\/wp-content\/uploads\/2026\/05\/mirror02.jpg?w=2048\")
<\/a><\/figure>\nIn this photo, which peers directly down the barrel of Roman\u2019s telescope, the photographer\u2019s camera is reflected in the primary mirror.<\/div>\nNASA\/Sydney Rohde<\/div>\n<\/figcaption><\/div>\n<\/div>\n<\/div>\nSince it\u2019s made of a specialty ultralow-expansion glass, the mirror will resist flexing, which can happen to materials during temperature changes (like going from balmy Earth conditions to the deep freeze of space). This preserves Roman\u2019s image quality, because if the primary mirror changed shape, it would distort the images from the telescope.<\/p>\n
\u201cWe\u2019re really proud of the amazing optical system we\u2019ve delivered for the Roman mission alongside our partners at L3Harris,\u201d said Josh Abel<\/a>, lead Optical Telescope Assembly systems engineer at NASA Goddard.\u00a0\u201cNow that it\u2019s assembled, aligned, and all shined up, we\u2019re ready to go.\u201d<\/p>\nNow, the Roman team is preparing to ship the observatory to the launch site at NASA\u2019s Kennedy Space Center in Florida in the coming weeks. NASA expects the mission to begin returning incredible cosmic vistas within several months after launch.<\/p>\n
To learn more about NASA\u2019s Roman mission, visit:<\/p>\n
https:\/\/nasa.gov\/roman<\/strong><\/a><\/p>\nThe Nancy Grace Roman Space Telescope is managed at NASA\u2019s Goddard Space Flight Center in Greenbelt, Maryland, with participation by NASA\u2019s Jet Propulsion Laboratory and Caltech\/IPAC in Southern California, the Space Telescope Science Institute (STScI) in Baltimore, and scientists from various research institutions.<\/p>\n
Media contact:<\/strong><\/p>\nClaire Andreoli<\/a>
NASA\u2019s Goddard Space Flight Center<\/a>, Greenbelt, Md.
301-286-1940<\/strong><\/p>\n\n\n\nAbout the Author<\/h3>\n<\/div>\n<\/div>\n\n\n\n![\"Ashley](\"https:\/\/www.nasa.gov\/wp-content\/uploads\/2023\/10\/cropped-cropped-proff-300x300.jpg\")
<\/div>\n\n\nAshley Balzer<\/h2>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\nAshley is the lead science writer for NASA’s Nancy Grace Roman Space Telescope.<\/p>\n<\/div>\n<\/div>\n<\/div>\n
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<\/figure>\n<\/p><\/div>\n<\/p><\/div>\n<\/p><\/div>\n\n\t\t\t\t\t\tNASA\/Sydney Rohde<\/span>\n\t\t\t\t\t<\/div>\n<\/figcaption><\/div>\n<\/p><\/div>\n<\/p><\/div>\n
Engineers at NASA\u2019s Goddard Space Flight Center in Greenbelt, Maryland, have completed their final inspection of a key element for the agency\u2019s Nancy Grace Roman Space Telescope: the primary mirror. This 7.9-foot (2.4-meter) mirror will collect and focus light from cosmic objects near and far, helping Roman capture stunning panoramas of space.<\/p>\n \u201cThe Roman engineering team laid eyes on the telescope for the final time before it, in turn, becomes the eyes of humanity, revealing the wonders of the cosmos,\u201d said J. Scott Smith, the Roman telescope manager at NASA Goddard. \u201cIt is a profoundly humbling moment to witness the culmination of hard work from so many dedicated individuals, teams, and partner organizations, including L3Harris.\u201d<\/p>\n On May 20, engineers turned the Roman observatory onto its side and deployed the \u201chood<\/a>\u201d that will be stowed for launch to protect the mirror. Then the team conducted a meticulous visual inspection to ensure no specks fell onto the mirrors during testing and confirm there are no defects in the coating or alignment.<\/p>\n \u201cWe developed a method of using a high-resolution camera equipped with a very powerful zoom lens to do a multi-purpose inspection,\u201d said Bente Eegholm<\/a>, optics lead for Roman\u2019s Optical Telescope Assembly at NASA Goddard. \u201cThe mirror passed with flying colors, keeping the mission on track for an early September launch.\u201d<\/p>\n The team carefully observed the optics along the path light will follow to the Wide Field Instrument<\/a> detector array and confirmed it remains in proper alignment following the observatory shake test<\/a>.<\/p>\n \u201cIn order to gather very sensitive measurements of objects strewn throughout space, all of Roman\u2019s components have to be ultraprecise,\u201d Eegholm said. \u201cThe primary mirror certainly delivers on that precision.\u201d<\/p>\n Roman\u2019s primary mirror sports a layer of silver less than 400 nanometers thick \u2014 about 200 times thinner than a human hair. The silver coating was specifically chosen for Roman because of how well it reflects near-infrared light. By contrast, the Hubble Space Telescope\u2019s mirror<\/a> is coated with layers of aluminum and magnesium fluoride to optimize visible and ultraviolet light reflectivity. Likewise, the James Webb Space Telescope\u2019s mirrors<\/a> have a gold coating to suit its longer wavelength infrared observations.<\/p>\n The Roman mirror is so finely polished that the average bump on its surface is only 1.2 nanometers tall \u2014 more than twice as smooth as the mission requires. If the mirror were scaled up to Earth\u2019s size, these bumps would be just a quarter of an inch high.<\/p>\n Since it\u2019s made of a specialty ultralow-expansion glass, the mirror will resist flexing, which can happen to materials during temperature changes (like going from balmy Earth conditions to the deep freeze of space). This preserves Roman\u2019s image quality, because if the primary mirror changed shape, it would distort the images from the telescope.<\/p>\n \u201cWe\u2019re really proud of the amazing optical system we\u2019ve delivered for the Roman mission alongside our partners at L3Harris,\u201d said Josh Abel<\/a>, lead Optical Telescope Assembly systems engineer at NASA Goddard.\u00a0\u201cNow that it\u2019s assembled, aligned, and all shined up, we\u2019re ready to go.\u201d<\/p>\n Now, the Roman team is preparing to ship the observatory to the launch site at NASA\u2019s Kennedy Space Center in Florida in the coming weeks. NASA expects the mission to begin returning incredible cosmic vistas within several months after launch.<\/p>\n To learn more about NASA\u2019s Roman mission, visit:<\/p>\n https:\/\/nasa.gov\/roman<\/strong><\/a><\/p>\n The Nancy Grace Roman Space Telescope is managed at NASA\u2019s Goddard Space Flight Center in Greenbelt, Maryland, with participation by NASA\u2019s Jet Propulsion Laboratory and Caltech\/IPAC in Southern California, the Space Telescope Science Institute (STScI) in Baltimore, and scientists from various research institutions.<\/p>\n Media contact:<\/strong><\/p>\n Claire Andreoli<\/a> Ashley is the lead science writer for NASA’s Nancy Grace Roman Space Telescope.<\/p>\n<\/div>\n<\/div>\n<\/div>\n
NASA\u2019s Goddard Space Flight Center<\/figcaption><\/figure>\n<\/a><\/figure><\/a><\/figure>
NASA\u2019s Goddard Space Flight Center<\/a>, Greenbelt, Md.
301-286-1940<\/strong><\/p>\nAbout the Author<\/h3>\n<\/div>\n<\/div>\n
<\/div>\nAshley Balzer<\/h2>\n<\/div>\n
Share<\/h2>\n<\/p><\/div>\n