NASA's newest flagship observatory lifted off Sunday on a mission to hunt for planets orbiting other stars, probe the mysteries of dark energy, and survey the cosmos on an unprecedented scale.

SpaceX launched the $4.3 billion Roman Space Telescope shortly after daybreak aboard a Falcon Heavy rocket configured with three booster cores. The observatory is headed for an observation point 1 million miles (1.6 million kilometers) from Earth — the same region of space occupied by the Webb Space Telescope, one of NASA's other premier instruments. That region, known as the second Lagrange point (L2), is gravitationally stable and keeps the Sun, Earth and telescope aligned, offering an uninterrupted vantage for deep-space observation.

The bus-sized telescope, named after the late Nancy Grace Roman, NASA's first chief astronomer, will take more than three months to reach its destination. Once in position, it will cast the widest gaze yet on the hidden parts of the universe from space, uncovering the unimaginable with unsurpassed speed.

"It's going to find thousands of supernovae, tens of thousands of planets, billions of galaxies and tens of billions of stars," said NASA science mission director Nicky Fox. "It's going to be able to do things that we've never been able to do before with its massive field of view."

Launch and a Presidential Call

Several minutes after the thunderous liftoff from Kennedy Space Center, the rocket's two reusable side boosters descended tail-first in a thrilling scene, producing sharp sonic booms as they touched down back at Cape Canaveral. Soon afterward, the telescope separated successfully from the rocket's upper stage, drawing applause from ground controllers. The mission adds to a growing NASA workload shouldered by SpaceX rockets, which have become the agency's workhorse for both crewed and science launches.

Fox was in tears as the events unfolded. "It's such a good day!" she said.

A couple of hours later, NASA Administrator Jared Isaacman was holding a news conference and predicting that the Roman Space Telescope would soon become a household name when his cellphone rang. President Donald Trump was on the line to offer congratulations.

"Boy, it looked beautiful on television," said Trump, who had visited Houston's Johnson Space Center on Friday to honor the Artemis II moon crew. "You're the hottest in space."

A Wider View Than Hubble

Roman's field of view is more than 100 times wider than that of NASA's Hubble Space Telescope, which continues to produce striking celestial imagery after 36 years in orbit. Webb joined the effort several years ago with an even narrower but razor-sharp vision capable of zooming in on objects nearly as old as the Big Bang.

The three orbiting observatories will work in concert — along with the European Space Agency's Euclid spacecraft and the National Science Foundation's Vera C. Rubin Observatory in Chile — to reveal some of the universe's biggest secrets. The pairing of wide-field surveyors like Roman, Euclid and Rubin with Webb's zoom capability reflects a broader division of labor in modern astronomy: discovery missions scan enormous swaths of sky, while more sensitive instruments follow up on individual targets.

Among the countless galaxies awaiting discovery are stars hosting planets. Once Roman spots these new worlds, the more powerful and sensitive Webb will take aim to fill in the blanks.

"Roman's vast reach will allow us to find the weird, the rare and the unusual," senior project scientist Julie McEnery said on the eve of launch. "We'll redefine what it means to find a needle in a haystack."

Shedding Light on Dark Matter and Dark Energy

Perhaps even more significantly, astronomers expect Roman to illuminate the dark matter and dark energy that make up most of the universe yet remain hidden from view. Scientists estimate that dark energy and dark matter together account for roughly 95 percent of the universe's contents, with ordinary matter — everything visible, from stars to planets — making up only a small fraction. Roman's catalog of galaxies will help scientists determine how quickly the universe is expanding under the influence of these puzzling, unseen forces.

Roman's defining strength is speed. According to McEnery, a month of Milky Way observations by Roman would take Hubble a century to complete. Roman should also make quick work of scanning the galactic bulge at the Milky Way's dead center, she added, providing the deepest look yet into the heart of our galaxy. By monitoring millions of stars for brief brightenings — a technique known as gravitational microlensing — Roman is expected to reveal planets that other methods often miss, including worlds orbiting far from their stars.

Besides a wide-field infrared camera that matches Hubble's sensitivity but operates 1,000 times faster, Roman carries an instrument designed to block out starlight. This experimental, eclipse-creating coronagraph will enable Roman to directly image any planet, however faint, that might be orbiting the masked star. The technology demonstration is aimed at proving techniques that future observatories could use to image Earth-like planets around other stars.

While Roman is not designed to search for life, Fox said it will pave the way for future observatories to answer what NASA considers the biggest question: "Are we alone? Is there another Earth 2.0 looking back at me?"

The telescope is also designed to be refueled, meaning that if a robotic tanker becomes available in the coming decade, its life could be extended.

A Tribute to Nancy Grace Roman

Launching nearly a year ahead of schedule and within budget, Roman is NASA's first space telescope named after a woman.

Retired NASA scientist Ed Weiler said the honor is long overdue. He coined the phrase "Mother of Hubble" for Roman, who hired him in 1978. After joining the newly formed NASA in 1959, she insisted that observatories placed above Earth's obscuring atmosphere could see farther and better. She died in 2018 at age 93.

"This is very, very fitting. I think Nancy would be very proud" that the namesake telescope will tackle some of the biggest lingering questions about the universe, such as dark energy, Weiler said.

Hubble launched in 1990 with a flawed mirror that required dramatic spacewalking repairs by astronauts. Roman's primary mirror is the same size as Hubble's — nearly 8 feet (2.4 meters) in diameter — and is actually surplus from a spy satellite program. The National Reconnaissance Office donated two leftover mirrors to NASA more than a decade ago for repurposing. The second mirror remains in storage. Once Roman completes its commissioning and begins science operations, its first images are expected to give astronomers their broadest infrared panoramic views of the universe to date.

This story was originally featured on Fortune.com.