How to watch NASA’s Artemis I lunar mission launch

Artemis I, a mission to the Moon that will test out a trio of key systems in NASA’s Artemis programme, is due for launch on 29 August. The uncrewed flight will test the Orion astronaut capsule, the 98-metre tall Space Launch System (SLS) rocket and the ground systems at Kennedy Space Center in Cape Canaveral, Florida ahead of a projected crewed mission to the Moon in 2025.

Watch the Artemis I launch live

Artemis seeks to end 50-year wait to return to Moon

Initiated in 2017, the Artemis programme aims to return humans to the Moon for the first time since the Apollo 17 mission in 1972, before establishing a base camp on the surface and a mini-space station in lunar orbit, allowing for longer-duration stays on the Earth’s satellite. Artemis also seeks to lay the foundations for future crewed missions to Mars.

Artemis’ initial aim was to land humans on the Moon in 2024, but NASA Administrator Bill Nelson said in November that this objective won’t be met. “2024 was not a goal that was really technically feasible,” Nelson told reporters. “We are estimating no earlier than 2025.” The projected launch in 2025 will involve four crew members, two of whom will spend about a week on the lunar surface after arriving via the Human Landing System (HLS). NASA has previously stated the plan of the Artemis III mission is for the landing crew to consist of at least one female astronaut.

Artemis I mission

On launch day, Artemis I will take off from Launch Complex 39B at Kennedy Space Center, the SLS rocket generating some 8.8 million pounds of thrust during liftoff. The SLS will carry the Orion into Earth orbit, before the rocket’s core stage separates from the spacecraft. The SLS’ interim cryogenic propulsion stage will then produce the thrust required to take the Orion out of Earth orbit and towards the Moon.

Once the Orion reaches the Moon, it will come to within 62 miles of the lunar surface, before settling into an orbit at an altitude of about 40,000 miles. After six days in lunar orbit, it will begin its journey back to Earth, where the final stage of the mission will test the craft’s ability to complete a safe return home. After re-entering the Earth’s atmosphere - its heat shield enduring temperatures of around 5,000ºF, roughly half as hot as the Sun - the Orion is due to splash down close to a US Navy recovery ship off the coast of Baja, California.

“This is a mission that truly will do what hasn’t been done and learn what isn’t known,” said Artemis Mission Manager Mike Sarafin. Orion will remain in space for a longer period than any other craft for astronauts has managed without docking to a space station – up to 42 days if all goes according to plan - and will “return home faster and hotter than ever before”, NASA says.

Artemis III first crewed Moon landing flight since 1972

As part of Artemis, NASA has pledged to land the first woman and the first person of colour on the Moon, with Artemis III slated as the programme’s first crewed Moon landing mission. Early Artemis flights will involve short stays on the Moon, the crew transferring directly from the Orion to a lunar-landing vehicle that will take them to the surface. After arrival on the Moon, the lander will double up as their base.

NASA recently awarded developmental contracts for initial design concepts to create fission power systems that could have an operational life expectancy of 10 years on the lunar surface. NASA hopes that such a system could be ready to be sent to the Moon for testing before the end of the 2020s. Among the goals of fission surface power technology is to help NASA to develop nuclear propulsion systems that can be used in deep space missions, such as sending a manned mission to Mars.

Once the mini-space station (known as the ‘gateway’) is built, astronauts will transfer to the lander via this staging point, and as the base camp begins to take shape - it is to be constructed near the Moon’s south pole - the facility will take over from the lander as the crew’s lunar habitat. The base camp is also set to include a lunar rover and a mobile home. The plan is for subsequent Artemis missions to grow in length to up to two months.

How to watch the Artemis I launch

Artemis I is scheduled to lift off from Launch Pad 39B at the Kennedy Space Center in Florida on Monday 29 August, within a two-hour window that opens at 8:33 am EDT.

The launch will be broadcast by NASA Television, the NASA app, and the agency’s website, nasa.gov. Coverage will also be available on the agency’s Facebook, Twitch and NASA YouTube channel, as well as in 4k on NASA’s UHD channel.

The launch countdown will begin on Saturday 27 August at 10:23 am EDT.

NASA will also be running a live stream of the launch and will provide audio of the launch control commentator, which can be accessed via cell phone and radio.

If bad launch weather or a minor technical issue triggers a delay on 29 August, NASA has slated alternative launch dates for 2 September and 5 September.