Finally, Europe’s long-awaited rocket is heading into space.
At 3 p.m. ET on Tuesday, a decade after the European Space Agency launched a plan for a powerful new vehicle that would carry the continent’s ambitions into orbit, Ariane 6 blasted off from the launch pad at Europe’s Spaceport in French Guiana. The vehicle reached orbit 18 minutes and 44 seconds after liftoff and, about an hour later, deployed a series of small satellites, after which the mission was deemed a success by its managers.
But an anomaly in the final phase of the flight caused Ariane 6 to deviate from its planned trajectory, preventing it from reaching the altitude needed to release the rest of its cargo. Officials at ArianeGroup, the French aerospace company that built the rocket, said it will take up to two weeks to analyze the data and determine what happened.
But Stéphane Israël, CEO of Arianespace, the company that operates the rocket, said the anomaly “has no impact on future launches.”
“We are perfectly on track to achieve a second launch this year,” he said at a press conference after the launch.
The rocket’s debut, after years of delay, was greeted with applause, whoops and cheers from ESA staff who watched the liftoff and were delighted to see European nations regain internal access to the final frontier, at least to some extent.
“This is a historic moment,” said Lucía Linares, head of space transportation strategy and institutional launches at ESA before the end of the final phase of the flight. “It’s a good thing for Europe. It’s also a good thing for the world.”
Europe’s need to go into space – for climate monitoring, navigation satellites and to explore the Moon, Mars and beyond – is growing year by year. A home-built rocket ensures that European missions will be prioritised on their own terms and that the continent’s space programme will not depend on the goodwill of non-European companies or international partners.
“We really need Ariane 6,” said Toni Tolker-Nielsen, ESA’s director of space transportation.
Critics of the Ariane 6 program, however, are unconvinced that the rocket will prove globally competitive in the long term, citing outdated technology and costs inflated beyond what was originally promised.
Before Tuesday, European countries had not had independent access to space since July 2023, when Ariane 5, the vehicle that preceded Ariane 6, last flew. Another, smaller ESA rocket, Vega-C, has been grounded since 2022 due to a flight failure.
In the past, many European missions have been carried out on board Russian Soyuz rockets. But Russia’s invasion of Ukraine led to a breakdown in relations between the two countries in 2022.
“Suddenly we found ourselves in a crisis situation, with no access to space,” Tolker-Nielsen said. Over the past year, key ESA missions have been flown aboard SpaceX vehicles, including the agency’s Earth Cloud Aerosol and Radiation Explorer, two Galileo navigation system satellites and the Euclid space telescope. Hera, an ESA spacecraft that will visit a pair of asteroids, is scheduled to be carried by SpaceX in the fall.
“When you don’t have it, you realize how important it is,” Tolker-Nielsen said of a European-designed way to get to orbit and beyond.
Ariane 6 is built by ArianeGroup, a French aeronautics company. It is the latest model in a family of rockets that have been in use since the 1970s.
The new rocket has a maximum height of 62 metres and is available in two versions. Ariane 62, equipped with two boosters, has a maximum take-off mass of 540 tonnes and is capable of carrying payloads of up to 10.3 tonnes into low orbit. Ariane 64 is equipped with four boosters with a maximum take-off mass of 870 tonnes and can carry up to 21.6 tonnes into low orbit.
The latest version of Ariane 5, on the other hand, could carry payloads of around 20 tonnes to low Earth orbit, while SpaceX’s Falcon 9 can carry nearly 23 tonnes.
ESA and Arianespace, a subsidiary of ArianeGroup, had aimed for a first flight by 2020, but technical challenges, the Covid-19 pandemic and an overly ambitious development schedule led to a four-year delay.
According to Philippe Baptiste, president of the National Center for Space Studies, the delay is partly due to a loss of technical knowledge, because too much time has passed between the development of Ariane 5, which began in 1988, and that of Ariane 6 in 2014.
Ariane 5 “was a very good launcher, and we kept it too long,” he said. The rocket was once one of the most frequently launched launchers on Earth, but it has recently been eclipsed by SpaceX’s Falcon 9, which offers comparable performance at a lower price.
“We didn’t make the changes at the right time, so we lost some capabilities in Europe,” Dr. Baptiste said.
Compared to its predecessor, Ariane 6 benefits from improvements, such as an upper stage powered by an engine that can be reignited up to four times. This makes it possible to carry out missions requiring orbits at different altitudes with a single rocket.
It was after the second relight that Tuesday’s Ariane 6 flight began to deviate from its flight plan. The vehicle’s auxiliary propulsion unit, which restarts the engine, fired up a third time and then immediately shut down as a safety precaution. Because of this problem, the upper stage engine failed to relight.
“We don’t know why it stopped,” said Martin Sion, ArianeGroup’s chief executive. “That’s something we’ll have to figure out when we have all the data.”
As a result, the upper stage will not be able to move out of orbit to burn up in Earth’s atmosphere and avoid contributing to the growing population of space debris, a goal that ESA has promoted with Ariane 6. Depending on the orbit, it could take years for the vehicle to fall back to Earth naturally.
“This is not a unique situation,” Sion said, adding that this is the scenario for many pitchers.
On Tuesday, ESA tested the capabilities of the two-thruster design with a series of small missions led by private companies, government agencies and research institutes. Some of the spacecraft, small CubeSats, were deployed into orbit around Earth, while others remained on board to collect data during the flight.
Two re-entry capsules were to be launched to demonstrate technology that could bring back cargo from space. But due to an anomaly, the re-entry capsules were not launched.
According to Mr. Sion, the main phases of the flight, namely the takeoff and the deployment of the satellites, went smoothly. The final phase of Ariane 6 allowed testing the behavior of the rocket’s upper stage in microgravity.
“A lot of missions don’t need to be relaunched in microgravity,” Sion said, noting that the rest of the mission went as planned. On future flights, “that’s a flexibility that we may or may not use,” he added.
The problems encountered during the final leg of Tuesday’s flight could, however, raise questions about Ariane 6’s competitiveness in the global space market.
In June, Eumetsat, the European government’s weather monitoring agency, moved the launch of a new satellite from an Ariane 6 to a Falcon 9. At a press conference following the launch, Mr. Israel responded to the development.
“What was demonstrated in the first 18 minutes was strictly sufficient to carry out a mission like Eumetsat’s,” he said.
Ariane 6 is also not partially reusable, a key factor that has reduced the cost of flying the Falcon 9 and boosted SpaceX’s competitiveness.
“It’s purely an economic issue,” says Laura Forczyk, a space industry analyst and founder of aerospace consultancy Astralytical. “If you throw away your rocket after every use, it’s not going to be cost competitive.”
Unfortunately, she added, in many ways this makes Ariane 6 “already obsolete, even before it is operational.”
Ariane 6 was supposed to be 50% cheaper than other ESA rockets, but its price has increased during its long development. ESA and ArianeGroup officials have remained evasive about the rocket’s total cost.
“Rocket reuse is going to be a long-term challenge,” said Clay Mowry, president of the International Astronautical Federation and a former head of Arianespace’s U.S. subsidiary. “They’ve made great strides, though,” he added, including improvements in ignition, vehicle flexibility and launch capability.
Walther Pelzer, the director general of the German space agency, said he believed Europe would master reusability in the future, but he did not think it was the only factor that would determine the success of Ariane 6.
“Whether a launcher should be reusable depends on the market,” he said, adding that Arianespace’s target customers for Ariane 6 are different from those using Falcon 9.
However long it takes a European rocket maker to achieve reusability, the new rocket is booked through mid-2028, with 30 flights planned for various customers. That includes 18 launches for Project Kuiper, Amazon’s effort to build a constellation of internet satellites in space that will attempt to rival SpaceX’s Starlink service.
After the maiden flight, another Ariane 6 rocket was scheduled to take off in December. Six more launches were planned in 2025; the following year, eight were planned, including ESA’s Plato mission, a space telescope designed to hunt exoplanets.
Despite the technical difficulties, Josef Aschbacher, ESA’s Director General, expressed his enthusiasm and relief at the press conference following the launch.
“Today we successfully launched Ariane 6,” he said. “This is an important milestone. Europe is back.”