Technicians at NASA’s Goddard Space Flight Center in Maryland joined the observatory’s inner and outer sections on 25 November, completing full assembly inside the centre’s main clean room.
The telescope is now entering its final testing phase ahead of launch preparations at Kennedy Space Center in mid-2026. Although officially scheduled to launch no later than May 2027, the mission team said it remains on track for a potential lift-off as early as late 2026 aboard a SpaceX Falcon Heavy, bound for an orbit about 1.6 million kilometres from Earth.
NASA associate administrator Amit Kshatriya said the milestone capped years of disciplined engineering: “This observatory will expand our understanding of the universe. As Roman moves into final testing, we’re focused on preparing for a successful launch on behalf of the global scientific community.”
Once operational, Roman will combine wide-field imaging with extremely sensitive infrared vision, enabling astronomers to explore phenomena ranging from dark matter and dark energy to isolated black holes and distant exoplanets.
NASA expects the telescope to reveal more than 100,000 planets, hundreds of millions of stars and billions of galaxies in its first five years.
The observatory carries two key instruments: the 288-megapixel Wide Field Instrument, and the Jet Propulsion Laboratory-built Coronagraph Instrument, a technology demonstrator designed to directly image planets around other stars.
By blocking starlight, the coronagraph will attempt to capture visible light images of older and colder giant planets – a leap towards answering the question of whether life exists elsewhere.
The Wide Field Instrument will gather data hundreds of times faster than the Hubble Space Telescope, producing around 20 petabytes over the primary mission. Roman will run three major surveys covering the distant universe, the changing sky and the central bulge of the Milky Way.
These will probe dark energy, chart the growth of galaxies and galaxy clusters, discover rogue planets and detect microlensing signals from otherwise invisible objects like isolated black holes.
A further 25 per cent of observation time will support community-selected research, with all data released immediately to the public in line with NASA’s open science standards.
Named after NASA’s first chief astronomer, Dr Nancy Grace Roman, the mission continues her legacy of making the cosmos accessible. NASA leaders said the telescope stands ready to deliver discoveries that will shape astronomy for decades.