It has been 50 years since humanity left space-boot prints on the Moon, but in a few short years, astronauts could once again walk the lunar surface.

Inverse breaks down exactly what NASA needs to do — and what they have already accomplished — in the quest to get mankind back on the Moon in the next decade.

In 2024, NASA plans to send the first woman and more men to the Moon as part of the agency’s Artemis mission. But getting to the Moon is no easy feat.

To make the journey a success, these crewed flights require the agency to clear a number of hurdles technical and safety first.

NASA has an ambitious timeline for its next lunar mission, targeting June 2022 for the launch of the uncrewed test flight to the Moon. Artemis I is the first phase for humanity’s return to the lunar surface, setting off a series of increasingly more complex trips to the Moon.

So, what comes next? Inverse has put together a timeline of the events we can expect leading up to humanity’s return to the lunar surface.

March and April 2022: Artemis I first steps

On March 17, NASA will bring out a fully assembled Space Launch System rocket with an Orion capsule out to Launchpad 39B at Kennedy Space Center in Florida. The rocket will make an achingly slow four-mile journey from the Vehicle Assembly Building to the launchpad in order to prepare for a wet dress rehearsal.

A wet dress rehearsal is when NASA engineers and other mission control members simulate a launch with a fully-fueled rocket. It differs from a static test fire in that the rockets are never ignited. This prepares Artemis team members for contingencies that may arrive during a real launch.

While the rocket will be rolled out on March 17, the actual wet dress rehearsal won’t take place until April 3, and will take two days in total. The rocket will be fueled up just prior to the wet dress rehearsal, which will take about eight hours.

If all goes well, the Artemis team will be one step closer to the launch of its first uncrewed mission: Artemis I, bound for the Moon.

June 2022: Artemis I launches

Scheduled to take off in June 2022, Artemis I kicks off the program officially. But there will be no humans on board this spacecraft.

To convey astronauts safely to the Moon, NASA first needs to send a test spacecraft there with no humans on board. But NASA will be sending up dummies with a battery of sensors to test forces that might be placed on Artemis II astronauts.

“This is a mission that truly will do what hasn’t been done and learn what isn’t known.”

Artemis I will take place on the first Space Launch Systems (SLS) vehicle, which will place Orion on a lunar transfer trajectory.

Instead of landing on the Moon, Artemis I will overshoot it by thousands of miles. During its trip, Orion will travel 280,000 miles from Earth and spend more time in space without docking at a space station than any other spacecraft of its kind has ever done before, NASA hopes — some three weeks.

After it makes its way beyond the Moon, Artemis I will, if all goes to plan, turn back and return to Earth.

“This is a mission that truly will do what hasn’t been done and learn what isn’t known,” Mike Sarafin, Artemis I mission manager at NASA Headquarters in Washington, said in a statement.

“It will blaze a trail that people will follow on the next Orion flight, pushing the edges of the envelope to prepare for that mission.”

The mission will also test “skip entry,” in which a spacecraft uses Earth’s atmosphere to partially aerobrake, slowing down its velocity enough to be captured by Earth. This fuel-saving measure has the added benefit of making landings more precise as the ship can cruise in the high atmosphere.

May 2024: Artemis II takes off

If Artemis I succeeds, then it is our turn. Artemis II is designed to carry humans on board the Orion spacecraft, although they will not land on the Moon, either. Instead, the spacecraft is designed to orbit the Moon and return back to Earth. This is similar to the Apollo program. While Apollo 11 was the first mission to land on the Moon, Apollo 8 and Apollo 10, both of which orbited the Moon with a full crew without landing on it.

Artemis II is currently scheduled to launch in May 2024.

It will be the first crewed mission to leave Earth’s low orbit in the 21st century, following in the flight path of Apollo 17, which made the trip in 1972.

“During this mission, we have a number of tests designed to demonstrate critical functions, including mission planning, system performance, crew interfaces, and navigation and guidance in deep space.” Bill Hill, deputy associate administrator of Exploration Systems Development at NASA, said in a statement.

The spacecraft will circle the Earth twice and periodically fire its engine in order to build up enough speed to propel it towards the Moon. It will briefly swing around the Moon before returning to Earth. It will fly about 4600 miles above the lunar surface. This will put astronauts at the farthest distance they will have ever been from Earth, eclipsing the Apollo 13 record of 157 miles above the Moon’s surface. Crew for the mission has not yet been decided, but it will consist of three American astronauts and one Canadian astronaut.

After it swings by the Moon, the spacecraft will use the Moon’s gravitational pull to slingshot itself back to Earth, where it will (fingers crossed) land safely.

2025: Artemis III takes center stage

Artemis I and II are the support acts to a killer headliner: Artemis III.

If NASA meets these two tests of its engineering ingenuity, then in 2025, we will finally come to the main event: A second crewed Artemis flight aboard the Orion spacecraft. But this time, the mission will land on the Moon.

Once it reaches the Moon, the spacecraft will connect with the lunar gateway, a small spaceship that will be orbiting the Moon. The gateway is already under construction, although NASA predicts it won’t be fully completed until 2026. A lot rests on whether the power and propulsion element of the gateway can be completed pre-2025, the agency says.

The element is a solar electric propulsion spacecraft. It will serve as a mobile command and service module, enabling communications between human and robotic expeditions to the lunar surface and ground control here on Earth.

The gateway will also allow astronauts to have access to different areas on the lunar terrain, including the Moon’s South Pole.

If all goes according to plan, two or more astronauts carried by Artemis III will touch down on the Moon’s South Pole. The South Pole is an unexplored region of the Moon. Previous missions have landed on the near side of the Moon that faces the Earth, but the South Pole lies on the far side that is obscured from our Earth-bound view.

And unlike the Apollo missions, this time when humans land on the Moon, they plan on being frequent lunar flyers. Ultimately the Artemis program wants to set up a sustainable presence of astronauts on the Moon, sending a crew up to the lunar surface once every year.

The initial missions will be focused on establishing the capabilities on the lunar surface to do that and building a gateway in orbit around the Moon, as well as a modern landing system for humans on the Moon.

And to do that, the agency needs a rolling supply of astronauts. Do you have what it takes to join the mission? Find out what two qualities you really need to make it onto NASA’s list of candidate astronauts here.