You can squeeze in 30 Earthsized planets between here and the Moon
AS THE INTERNATIONAL SPACE STATION NEARS THE END OF ITS LIFE, WE LOOK AT THE PLANS TO BUILD A NEXT-GENERATION OUTPOST NEAR THE MOON
Adistance of 410,000km. That’s how far away astronauts will be when they’re living aboard a new space station that’s set to be built in orbit around the Moon. To put it in context, you could fit 30 Earth-sized planets across that distance. Currently in development, the ‘Lunar Orbital Platform-Gateway’ will take humans further from Earth than ever before. Known as Gateway for short, and previously named Deep Space Gateway, the space station is being developed by NASA and other space agencies, including the European Space Agency (ESA) and Russia’s Roscosmos. It will be a replacement for the International Space Station (ISS), which this month celebrates its 20th birthday. While the fate of the ISS hangs in the balance, one thing is certain – the White House has asked NASA to stop funding the ISS in 2025. Instead, the Trump administration wants the space agency to focus its efforts on returning to the Moon and then to Mars. And that’s where Gateway comes in.
“Gateway has been developed to take humans beyond low Earth orbit and out into the cosmos,” says Dr James Carpenter, an ESA scientist working on the new space station. “The idea is that it provides an infrastructure for future exploration, and somewhere we can learn how to live and work in deep space.” Whereas the ISS flies in low Earth orbit, just 400km (250 miles) above our heads, Gateway will be hundreds of thousands of kilometres away.
Gateway will make the surface of the Moon one short hop for astronauts, allowing them to explore like never before, and creating a new generation of Moonwalkers in the process. It’ll also enable a new wave of science experiments to probe some of the mysteries of deep space. In the longer term, it is hoped that Gateway will act as a service station for spacecraft taking astronauts to Mars and beyond. But building a space station way out in lunar orbit is strewn with challenges. How do you lug tonnes of hardware all the way out to the Moon? How do you keep astronauts safe? Unlike those on the ISS, the astronauts aboard Gateway won’t be shielded from cosmic radiation by Earth’s magnetic field. And they can’t just be whisked back home if something goes wrong. Aboard the ISS, they can return in hours. The journey between Earth and the Moon takes days.
SIZE MATTERS
Gateway will be different from the ISS. For starters, it will be much smaller. At 109m long and 73m wide, the ISS is slightly larger than an American football field. The main body of Gateway will be 30-35m long and 5m wide. For comparison, a typical London Underground carriage is around 17m long and 3m wide. And while the ISS is occupied by at least three astronauts 365 days a year, Gateway will be occupied by four crewmembers, but only for 30 days a year, due to the cost of getting astronauts there. The rest of the time, it won’t have a soul on board.
Those lucky enough to make it to Gateway will be in for one heck of a ride. On the space station’s most likely path around the Moon, astronauts will pass within 3,200km of the lunar surface. “Once a week, you would see the Moon very large beneath you,” says Jim Clark, an aerospace engineering PhD student, who works in a lab that conducts research on the design and controls of Gateway. “It would fill the view out of the window.” At the furthest point on its orbit, however, Gateway will be about 70,000km from the Moon and 410,000km from Earth. The two celestial bodies will be nothing but distant spheres: unprecedented isolation.
This far away, communications will be a huge challenge. If the same radio technology was used aboard Gateway as is used on the ISS, the data rate would be 1/160,000th that on the ISS. “This would only be useful for minimal status signals and possibly voice 2