The Artemis program is NASA’s plan to return humans to the Moon as a springboard for an eventual trip to Mars.
Twelve men walked on the moon between 1969 and 1972 and one of Artemis’ goals is to put the first woman and person of color on the lunar surface.
The first test flight of an uncrewed Artemis rocket is due to take place on Monday.
The name Artemis was chosen to echo that of the Apollo program.
Artemis, in Greek mythology, was the twin sister of Apollo and a goddess associated with the Moon.
Here is an overview of the Artemis program:
Artemis 1 is a test flight of the 322-foot (98-meter) Space Launch System rocket and the Orion crew capsule that sits atop.
Liftoff is scheduled for Monday at 8:33 a.m. (12:33 p.m. GMT) from Kennedy Space Center in Florida.
Manikins fitted with sensors will take the place of crew members on the flight, recording vibration, acceleration and radiation levels.
Orion will orbit the Moon before plunging into the Pacific Ocean.
Scheduled for 2024, Artemis 2 will be a crewed flight that will orbit the Moon but not land on the surface, similar to what Apollo 8 did.
The four crew members will be named before the end of the year. A Canadian should be among them.
The third Artemis mission will be the first to send astronauts to the Moon since Apollo 17 in December 1972.
NASA, for the first time, will land a crewed spacecraft on the South Pole of the Moon, where water in the form of ice has been detected.
Previous moon landings have taken place near the equator.
Artemis 3 is scheduled for 2025 but may not happen until 2026 at the earliest, according to an independent audit of the program.
Beginning with Artemis 3, NASA plans to launch crewed missions about once a year.
NASA has selected Elon Musk’s SpaceX to build the Artemis 3 lunar lander.
SpaceX’s Starship, which is still under development, will serve as a shuttle from Orion’s crew capsule to the lunar surface and back.
The Artemis program also plans to build a space station called Gateway which will orbit the Moon.
The launch of the first two elements – the habitation module and the power and propulsion system – is planned for the end of 2024 at the earliest by a SpaceX Falcon Heavy rocket.
Orion crews would be responsible for assembling Gateway.
Astronauts would spend between 30 and 60 days at Gateway and eventually gain access to a lander that would allow them to travel to the Moon and back.
Gateway would also serve as a stopping point for any future journeys to Mars.
The ultimate goal of the Artemis program is what NASA calls the “next giant leap – human exploration of Mars.”
NASA will use knowledge gained from Artemis about next-generation spacesuits, vehicles, propulsion, resupply and other areas to prepare for a trip to Mars.
The goal is to learn how to maintain a human presence in deep space for a long time.
The creation of a “base camp” on the Moon is part of the plan, with astronauts remaining on the lunar surface for up to two months.
While a trip to the Moon only takes a few days, a trip to Mars would take at least several months.