Astronauts are returning to the moon…well, sort of

By the end of 2024, astronauts are due to return to the Moon for the first time in more than half a century. Well, sort of. As part of NASA’s Artemis II mission, four astronauts—Reid Wiseman, Victor Glover, Christina Hammock Koch and Jeremy Hansen—will travel 7,400km beyond the Moon, swing around and return to Earth, without landing on the lunar surface. Their ten-day voyage will test the Space Launch System (SLS) rocket and the Orion spacecraft for future missions. As well as being the first humans to reach the vicinity of the Moon since those of Apollo 17 in 1972, Mr Glover, Dr Koch and Mr Hansen will be the first black man, first woman and first non-American respectively to leave Earth orbit.

The earliest that Artemis II can launch is November, and it may be delayed to 2025. It will certainly be beaten to the Moon in May by the latest mission in the Chinese Lunar Exploration Programme (known as Chang’e). Like Chang’e 5 before it in 2020, Chang’e 6 aims to deliver a robotic lander to the Moon’s surface, collect a few kilograms of rocks and bring them back to Earth. The target location is on the far side of the Moon and the mission will also carry instruments from France, Italy, Pakistan and Sweden.

In September Japan will attempt to join the Mars club by launching its Martian Moons Exploration (MMX) mission to study the planet’s moons, Phobos and Deimos. Because the moons are too small to gravitationally capture the spacecraft, MMX will instead enter a “quasi-satellite orbit” around them. It is due to land on Phobos in 2025 to scoop up rock samples for return to Earth by the end of the decade.

In October NASA plans to launch Europa Clipper, a probe dedicated to studying the habitability of one of Jupiter’s moons. The observation in 2012 of water vapour near Europa’s south pole reignited interest among planetary scientists in studying the big moons of Jupiter and Saturn, which seemingly harbour subsurface oceans of water, and could be home to alien life. When it arrives at Europa in 2030, Europa Clipper will perform 45 fly-bys of the moon, varying in altitude from 2,700km to 25km, to study Europa’s magnetic field and icy shell, and the nature of the water and rocks underneath.

In December the Indian Space Research Organisation aims to build on the success of its Chandrayaan-3 mission in August 2023, which landed a spacecraft near the Moon’s south pole, by launching Shukrayaan to Venus. This will be the first dedicated mission to Earth’s “evil twin” since Japan’s Akatsuki in 2010. Scientists hope to study everything from the chemistry of Venus’s atmosphere to its lava flows—and find out whether or not the planet harbours phosphine (a molecule suspected to be present, which is normally associated with life).

Closer to home, private companies will be testing out new rockets. Blue Origin, Jeff Bezos’s company, could test its New Glenn rocket for the first time in 2024. It is a reusable heavy-lift vehicle, capable of placing 45 tonnes into low-Earth orbit, compared with 64 metric tonnes for SpaceX’s Falcon Heavy, or 95 tonnes for the expendable SLS. Rocket Lab, a startup, plans to fly its reusable Neutron rocket for the first time. ArianeGroup’s Ariane 6, an expendable rocket, may also make its maiden flight in 2024.

All these rockets, though impressive, will eventually be dwarfed by SpaceX’s reusable Starship which, when it works, will be capable of lofting 150 tonnes into orbit. Expect to see more trials of that behemoth in 2024. ■

Alok Jha, Science editor, The Economist