NASA’s Artemis II astronauts fired their engines and surged toward the Moon on Thursday night, finally breaking free of the low Earth orbits that have kept humanity tethered since the end of the Apollo era.

The critical translunar ignition occurred about 25 hours after launch, sending the three Americans and one Canadian on a path for a lunar flyby early next week. Their Orion spacecraft slipped out of Earth orbit precisely on schedule and set course for the Moon, roughly 250,000 miles (400,000 kilometres) away.

NASA’s Lori Glaze said at a news conference: “Ladies and gentlemen, I am so, so excited to be able to tell you that for the first time since 1972 during Apollo 17, human beings have left Earth orbit.”

The burn went flawlessly, she added.

Canadian astronaut Jeremy Hansen said he and his crewmates were pressed against the capsule windows, mesmerised by the “phenomenal” sight of Earth shrinking behind them. Their faces were so close to the glass they had to wipe it clean afterward.

Hansen said: “Humanity has once again shown what we are capable of, and it’s your hopes for the future that carry us now on this journey around the moon.”

NASA kept the crew in Earth orbit for a full day to thoroughly test the capsule’s life-support systems before committing to the lunar journey.

Now headed for deep space, Artemis II serves as the first major step toward NASA’s ambitious plans for a sustained lunar presence and eventual Moon base.

Commander Reid Wiseman, pilot Victor Glover, mission specialist Christina Koch and Hansen will swing past the Moon, make a U-turn, and return home without landing.

In doing so, they will travel farther from Earth than any humans since Apollo 13 in 1970 and could set a new speed record during reentry on April 10.

Glover, Koch and Hansen have already entered the history books as the first Black person, first woman and first non-American to fly toward the Moon. All 24 Apollo lunar travellers were white men.

Glover said after seeing Earth from pole to pole: “Trust us, you look amazing. You look beautiful. And from up here you also look like one thing: homo sapiens. No matter where you’re from or what you look like, we’re all one people.”

To set the tone, Mission Control woke the crew with John Legend’s “Green Light” featuring Andre 3000, followed by cheers from NASA teams.

Glover replied: “We are ready to go.”

Minutes before the engine firing, controllers cleared the crew for departure, calling it “humanity’s lunar homecoming arc.” The spacecraft is using a free-return trajectory that relies on the gravity of Earth and the Moon to trace a giant figure-eight loop back home. The burn pushed Orion to more than 24,000 mph (38,000 kph) to escape Earth’s grasp.

Wiseman said: “I’ve got to tell you, there is nothing normal about this. Sending four humans 250,000 miles away is a herculean effort, and we are now just realizing the gravity of that.”

Flight director Judd Frieling said his team stayed focused during the burn but would later reflect on the historic moment.

Frieling told reporters: “I suspect everybody understands that this is a once-in-a-lifetime moment.”

The next big milestone comes Monday with the lunar flyby. Orion will pass about 4,000 miles (6,400 kilometres) beyond the Moon, offering rare views of the lunar far side and even treating the crew to a total solar eclipse from space.

While still waiting to leave Earth orbit earlier Thursday, the astronauts enjoyed sweeping views of the planet from tens of thousands of miles away. Koch reported seeing entire coastlines and even the South Pole, her former research territory.

NASA hopes the test flight will pave the way for the full Artemis program, including a crewed Moon landing targeted for 2028.

The so-called lunar loo may need some tweaks, though. Orion’s toilet failed shortly after reaching orbit Wednesday night. Mission Control talked Koch through some emergency fixes until it worked, forcing the crew to use contingency urine collection bags in the meantime.

Those same bags were pressed into extra service Thursday. After a water dispenser valve issue appeared post-launch, controllers had the astronauts fill empty urine pouches with more than 2 gallons (7 litres) of drinking water using straws and syringes—just in case the problem returned before the trip to the Moon.