NASA launches $4.3bn Roman telescope to unlock universe's biggest mysteries

NASA has launched its newest flagship space observatory on a mission to investigate some of the most profound mysteries in the universe, from the nature of dark energy to the search for planets beyond our solar system.

The $4.3bn Nancy Grace Roman Space Telescope blasted off shortly after dawn on Sunday aboard a powerful SpaceX Falcon Heavy rocket from NASA's Kennedy Space Center in Florida.

The telescope is now travelling towards Lagrange Point 2, a stable region of space about 1.6 million kilometres (1 million miles) from Earth where it will operate alongside the James Webb Space Telescope. The journey is expected to take more than three months.

Roman is scheduled to operate for at least five years, although NASA says its mission could potentially be extended for another five years. The spacecraft has been designed with the possibility of future refuelling, meaning a robotic servicing mission could further extend its operational life if suitable technology becomes available.

The bus-sized observatory has been built to conduct enormous surveys of the cosmos while investigating questions about how the universe formed, evolved and continues to expand.

Among its primary goals is the search for exoplanets - worlds orbiting stars beyond our Sun. Scientists expect Roman to identify thousands of previously unknown planets and provide the first large-scale statistical picture of planetary systems across the galaxy.

The telescope will also investigate dark matter and dark energy, two mysterious components believed to account for the vast majority of the universe.

Scientists estimate that ordinary matter - including stars, planets, gas and dust - makes up only about 5 percent of the universe. Dark matter is thought to account for roughly 27 percent, while dark energy makes up the remaining 68 percent.

Although neither dark matter nor dark energy can be directly seen, their effects can be detected through the way galaxies, stars and the universe itself behave.

Roman's principal survey is expected to examine more than two billion galaxies over a period of more than a year. By mapping this enormous population of galaxies and studying exploding stars known as supernovae, researchers hope to determine more precisely how rapidly the universe is expanding.

NASA Science Mission Directorate chief Nicky Fox said the telescope would dramatically expand scientists' ability to observe the cosmos.

Roman is expected to detect thousands of supernovae, tens of thousands of planets, billions of galaxies and tens of billions of stars, she said.

The launch proceeded smoothly, with Falcon Heavy's two side boosters returning to Earth and landing at Cape Canaveral shortly after liftoff. The telescope then separated successfully from the rocket's upper stage, prompting cheers and applause from NASA's mission control team.

Fox became emotional as the successful launch unfolded.

"It's such a good day," she said.

The mission has also reached orbit nearly a year earlier than originally planned and within its allocated budget.

A telescope named for a NASA pioneer

The observatory is named after Nancy Grace Roman, NASA's first chief astronomer and a pioneering figure in the development of space-based astronomy.

Roman joined the newly established NASA in 1959 and became a strong advocate for placing observatories above Earth's atmosphere, where they could obtain clearer views of the universe.

Her work helped lay the groundwork for the Hubble Space Telescope, earning her the nickname "Mother of Hubble".

Roman died in 2018 at the age of 93.

Ed Weiler, a retired NASA scientist who worked with Roman, said naming the new observatory after her was a fitting tribute.

He said Roman would have been proud to see the telescope pursuing answers to some of astronomy's most persistent questions.

Hubble, Webb and Roman form powerful cosmic team

Roman will become the latest member of a growing international fleet of powerful observatories studying the universe.

Its field of view is more than 100 times wider than that of Hubble, which has been observing the cosmos for decades and continues to produce detailed images of distant celestial objects.

The James Webb Space Telescope, launched in 2021, has a different but complementary role. Its highly sensitive instruments allow astronomers to examine extremely distant objects and study some of the earliest galaxies formed after the Big Bang.

Webb has already challenged established theories about the early universe by revealing galaxies that appear to have formed and grown much earlier than scientists had expected.

NASA describes Roman as a wide-angle camera and Webb as a powerful zoom lens.

Nicky Fox said Roman would effectively provide a much broader view of the universe, complementing the detailed observations produced by Hubble and Webb.

The three telescopes will work alongside other major observatories, including the European Space Agency's Euclid mission and the Vera C Rubin Observatory in Chile.

Together, the observatories are expected to provide an unprecedented amount of information about galaxies, stars, planets and the fundamental forces shaping the universe.

Roman will be particularly useful for surveying enormous regions of space quickly. NASA scientists say observations of the Milky Way that would have taken Hubble around a century could potentially be completed by Roman in about a month.

The telescope will also help identify intriguing objects for Webb to study in much greater detail.

Scientists expect the combination of Roman's huge field of view and Webb's extraordinary sensitivity to transform the search for distant worlds and the study of the early universe.

The mission survived repeated attempts during Donald Trump's first and second presidential administrations to cancel or sharply reduce funding for the project. Congress intervened on each occasion to preserve the telescope's financing.

Now in space, Roman begins a mission that NASA hopes will reshape scientists' understanding of the universe - and answer questions that have remained unresolved for generations.