Artemis II was set to launch in February, but a leaky situation has caused a delay. Find out about the challenges NASA is facing with this moon mission.

NASA is inviting the public to join the agency's Artemis II test flight as four astronauts venture around the Moon and back to test systems and hardware needed for deep space exploration.

NASA aims to establish a long-term presence on the Moon and Mars through learnings of Artemis II.

In the early hours of February 2, with more than 700,000 gallons of cryogenic propellant flowing into the Space Launch System at Kennedy Space Center, a sensor flagged what mission controllers were hoping they would not see: hydrogen concentrations climbing past allowable limits at the tail service mast umbilical,

Artemis II will then use the push from Orion’s service module to break free from Earth’s orbit. It will take four days to go around the far side of the Moon and then return to Earth using the Earth-Moon gravity field. The daring journey will end in the Pacific Ocean off the coast of San Diego.

During the two-day dress rehearsal, running through launch-day procedures, crews found a liquid hydrogen leak in part of the rocket.

If the fueling test goes well, the Artemis II flight around the moon and back could take off as early as Feb. 8.

The O2O system could send more data to Earth than ever before, NASA says.

NASA has finally brought a stubborn hydrogen leak on its new Moon rocket under control, removing one of the last major technical risks before four astronauts climb aboard for the first crewed lunar voyage in more than 50 years.

The Artemis II mission will bring in experts from across the country, and that includes scientists in Boulder at the center for the National Oceanic and Atmospheric Administration.