The rocket was set to make history, carrying satellites on what would be the first-ever orbital launch from the U.K. on Monday night. But Virgin Orbit says its LauncherOne rocket "experienced an anomaly" just before it could deliver its payload, and the craft was lost.

The mission had been dubbed "Start Me Up," channeling the Rolling Stones to herald a new era of British space travel. Now, officials say, they'll start again, noting that the mission set a new precedent for the U.K. and proved the viability of their long-term plans.

"Yes, space is hard, but we are only just getting started." said Melissa Thorpe, head of Spaceport Cornwall, in a statement about the operation.

The setback came on the precipice of success

The craft came tantalizingly close to completing its mission, needing just one more successful phase of engine burn before releasing its satellites into orbit. That would be "when we can start popping Champagne corks and dancing," Virgin Orbit's Chris Relf told the thousands of people watching a livestream video of the launch.

But around 24 minutes after making that statement, Relf, Virgin Orbit's director of systems engineering and verification, somberly announced that the craft had "suffered an anomaly which will prevent us from making orbit for this mission."

It wasn't clear what might have caused the anomaly, or how it put a premature end to what had been a highly anticipated launch — a vital step in the UK Space Agency's ambitious plan to become a major player in the spaceport and satellite-launching business.

"Cosmic Girl" jet took the rocket to high altitude

The launch plan for LauncherOne called for it to be carried to an altitude of 35,000 feet by Cosmic Girl — a Boeing 747 that Virgin Orbit converted into an aerial launch tool. The aircraft took off from Spaceport Cornwall in southwest England, and safely returned to its landing strip after releasing LauncherOne.

For a time, LauncherOne performed exactly as planned: after separating from Cosmic Girl, its first-stage engine, NewtonThree, ignited and blasted the craft above the threshold of space.

After a successful stage separation, LauncherOne's second-stage engines lit up to take it closer to the satellites' desired orbit level. The craft also shed the fairing around its nose, to prepare for the looming payload separation. It cut its engine as it began to coast halfway around the Earth.

Then came the "barbecue roll"

While coasting, LauncherOne also started rotating in the sunshine, in a maneuver NASA has long called passive thermal control — but for seemingly just as long, it's been known by a catchy nickname: the "barbecue roll." The goal is to expose all sides of a spacecraft to the sun, like a rotisserie above a fire's flames.

"Essentially, we are rifling through the atmosphere," Relf said. "What this does is, it avoids one side of the stage from getting too hot, and the other from getting too cold."

"We're waiting for the rocket to coast halfway around Earth, deploy its payload, and downlink telemetry," Virgin Orbit said as it narrated the craft's progress on Twitter.

The plan called for the engine to reignite so engineers could ensure the satellites were deployed at their target altitude of 555 kilometers in a sun-synchronous orbit, or SSO. But the craft didn't reach orbit.

Nine satellites were lost

Virgin Orbit says it's reviewing the flight data to determine exactly what went wrong.

"The failure resulted in the loss of nine satellites," reports Space.com. "Those payloads are an in-orbit manufacturing experiment by the U.K. company Space Forge; several U.K. defense cubesats, including two for studying the ionosphere, the upper layer of Earth's atmosphere where space weather occurs; and an experimental global navigation satellite co-funded by the European Space Agency."

More launches will follow, said Matt Archer, the UK Space Agency's director of commercial spaceflight.

"While this result is disappointing, launching a spacecraft always carries significant risks," Archer said. "Despite this, the project has succeeded in creating a horizontal launch capability at Spaceport Cornwall, and we remain committed to becoming the leading provider of commercial small satellite launch in Europe by 2030, with vertical launches planned from Scotland."