Canadian astronauts will face a lonely existence on the new Lunar Gateway
Canada's most visible contribution will literally be a helping hand — the Canadarm 3
Now that Canada is officially part of a plan to return humans to the moon, our participation in the program will open up opportunities for Canadian astronauts to visit the lunar outpost, and even walk on the moon.
Canada has a long history of space flight. We were the third country in space after the former Soviet Union and the U.S., with our Alouette One satellite that was launched in 1962, just a year after Yuri Gagarin became the first human to orbit the Earth. Since then we have continued to build satellites, provided scientific instruments that have flown to other planets, developed robotics and trained astronauts as participants on international space programs. So it is fitting that our tradition of providing technology and expertise on space flight continues back to the moon.
Canada's contribution will literally be a 'helping hand'
Our most highly visible contribution will literally be a helping hand with a newer version of Canadarm, a robotic space crane that was used first on American space shuttles. A larger version than the original then became a permanent fixture on the International Space Station (ISS).
A Lunar Gateway arm, to be known as Canadarm 3, could be used to assemble the modules of the station itself, as well as to catch and release spacecraft coming and going from the Earth and from the surface of the moon. The new arm will be far more sophisticated than the current versions, which are flown manually, because the Gateway will not be occupied full-time, so the arm will need to have enough built-in intelligence to work autonomously on its own.
First Canadian moonwalker
Hopefully, the commitment by the Canadian government will include funds for smaller companies to provide scientific instruments for exploration of the moon and deep space. But as international partners, we will be offered rides for our Canadian astronauts, which raises the very real possibility that the first Canadian moonwalker is alive today.
It will take many years before a Canadian flag is planted on the moon because construction of the outpost is expected to take until 2026 and the first missions there will not involve landing on the lunar surface. And those astronauts who live on the station for up to three months at a time will have a very different experience than those on the current space station. For one thing, they will be forced into a much smaller, cramped space, about one-seventh the size as the living space in the ISS.
And instead of the spectacular view of the Earth passing 400 km below enjoyed by everyone who has been to the space station, the scene out the window of Gateway will be much darker, with both the Earth and the moon visible together, but each likely appearing smaller than your thumb most of the time, as seen from a great distance.
Eventual home for the Lunar Gateway
In order to remain in contact with the Earth at all times, and not disappear behind the moon for periods, Gateway will be placed into what's called a halo orbit which extends far beyond the moon to a Lagrange point — a spot in space where the gravity from the sun and Earth balance it out.
China recently sent a relay satellite into this orbit to communicate with its Chang'e 4 robot that landed on the far side of the moon. That means Gateway astronauts will be farther away from Earth than humans have ever ventured, giving them a much stronger sense of isolation.
Gateway residents will also be exposed to much higher doses of cosmic radiation out beyond the Earth's protective Van Allen Belts, which are regions of energetic particles that surround our planet and act as a shield for life below. The moon and its vicinity are beyond these belts, so radiation exposure from space is higher, posing a health hazard that is also a big concern for future astronauts travelling to Mars.
The Lunar Gateway has been criticized as the wrong way to return to the moon. Critics say it would be better to land directly, or since we have already been there, skip the moon altogether and focus on a mission to Mars. Whatever the choice, Canada as a space faring nation will be along for the ride.