The Lunar Gateway: a shortcut to Mars?
Nasa plans to put a module in orbit around the moon as a springboard for missions to the red planet — and beyond,
SPACEFLIGHT will mark an important milestone this year — when Nasa celebrates the 50th anniversary of US astronauts reaching the moon. In December 1968 Frank Borman, Jim Lovell and Bill Anders, on Apollo 8, swept over the lunar surface and captured bright blue images of Earth rising above the grey plains of the moon. It was one of the most dramatic space missions ever flown. Manned landings followed, but after a few years, the US lost interest in lunar space flights.
But now Nasa has revealed plans to return to the moon and has asked European scientists and industry leaders to join the agency in a bold plan aimed at rebooting humanity’s conquest of the solar system — in the form of an international manned station that will orbit the moon within the next decade.
The proposed station, the Lunar Orbital PlatformGateway, known as Gateway, will allow astronauts to develop techniques that will open up the lunar surface to exploration and exploitation. At the same time, the station will help humans hone survival skills in deep space in preparation for future manned missions to Mars, Nasa says.
Taking part in the station’s construction would cost Europe more than £1 billion and a decision on whether to become involved will be taken at a meeting of European science ministers next year. If ministers give the goahead, the European Space Agency (ESA) — of which Britain is a key member — would join other international partners Nasa is recruiting to its Gateway project. These include the space agencies of Russia, Canada and Japan.
‘‘Essentially, Gateway will be a robotic outpost that will be visited by groups of astronauts, initially for weeks and then for months at a time,’’ said David Parker, director of human spaceflight and robotic exploration for ESA and a keen supporter of the project.
‘‘They will learn how to survive in deep space and deal with problems such as radiation and meteorites. At the same time they will also direct robot craft that will explore the moon’s surface.’’
A goahead for Gateway would also bring to an end the hiatus in manned space exploration that has lasted almost a decade. Since the grounding of the space shuttle, human spaceflights have been restricted to launches of Russia’s Soyuz space capsule, which is used to ferry crew and supplies to the International Space Station (ISS), and the few missions taken by taikonauts on China’s fledgling spacecraft.
Gateway should change that — and it will do so by taking advantage of a major advance in US space engineering which will occur when Nasa begins flights with its new deepspace capsule,
Orion, and its launcher, the Space Launch System, in a few years. These will form the core components of Gateway along with modules similar to those now used as stores and crew quarters on the ISS, though Nasa stresses Gateway will be considerably smaller than their current Earthorbiting space station.
And key to their lunar station will be the extraction, from lunar soil, of minerals, chemicals, and — most important — water.
‘‘Recent evidence suggests comets and asteroids have bombarded the moon for billions of years, depositing water — in the form of ice — on to its polar regions,’’ Mahesh Anand, reader in planetary science and exploration at the Open University, said.
Scientists like Anand believe it should be possible to use that water to turn the moon into a refuelling station for longterm missions to Mars and beyond. Ice would be harvested, melted and electrolysed — using power generated by solar panels — into its hydrogen and oxygen components.
‘‘You could then use that hydrogen and oxygen as liquid propellents,’’ Anand said.
‘‘That is what powered the space shuttle’s main engines after all. Then you could use the moon as a refuelling post to power spaceships to Mars.’’
It remains a faroff goal. For a start, astronomers do not have precise details of the most promising places to find water on the moon.
Finding those sources will not be easy, but not impossible — thanks to Gateway. It will orbit the moon from a height of a few hundred miles and from there astronauts will control robot rovers remotely and send them trundling over the lunar surface to pinpoint areas rich in water ice. Samples could even be sent back to the space station by unmanned spacecraft.
Scientists at Esa are already working with Canadian and Japanese space agencies to prepare a robot mission called Heracles, which would travel to the moon sometime in the next decade and which would use the Gateway as a halfway house to store lunar samples before being sent back to Earth.
‘‘It will be much easier to drive a robot rover from a height of only a few hundred miles above the moon than from the Earth which is 250,000 miles away,’’ Anand said.
European astronauts recently guided an automated rover on Earth using controls in the ISS — which orbits the Earth at roughly the same height that Gateway would orbit the moon. The technology is already well tested, ESA says.
‘‘The moon has lain virtually undisturbed for the last 4.5 billion years,’’ Parker said.
‘‘It is a museum of the history of our solar system. And yes, we visited it when we briefly landed Apollo spacecraft there. However, that was the equivalent of going to a museum, heading straight to the gift shop and then leaving. It is the dusty corners of a museum where you find the really interesting stuff — and that is where we are going to go with Gateway.’’
This point is backed by James Carpenter, a member of ESA’s lunar exploration team.
‘‘The major scientific impact of Gateway will undoubtedly come from the way it will open up access to the lunar surface,’’ he said.
‘‘However, there are many other areas of research that will benefit.
‘‘Apollo took astronauts into deep space but the missions lasted a few days. We are talking of spending months at Gateway.
‘‘We will be able to study the effects of radiation on human physiology; we will be able to collect dust particles that come from asteroids or comets or possibly objects outside our solar system. We will be able to study the interaction of the sun and the moon with Earth’s magnetosphere. Gateway would also be ideal for launching tiny CubeSat satellites and other devices that could open up exploration of the solar system.’’
Astronomers are also keen to use Gateway as a platform for assembling deepspace observatories, in particular to study lowfrequency radio waves that could give new insights into the early universe not long after its big bang birth 13.8 billion years ago.
In addition, Gateway’s location will take it far outside Earth’s protective magnetic field and will leave astronauts exposed to far more intense radiation than is experienced on the ISS. This will provide key opportunities to study the longterm impact of radiation on humans in deep space.
‘‘We will ultimately translate that experience toward human missions to Mars,’’ William Gerstenmaier, an associate administrator at Nasa headquarters in Washington, said.
The critical point about the Gateway project was that it did not depend on new or untested technologies, Carpenter said.
‘‘A huge expertise was built up during the design and assembly of the International Space Station. We know the risks involved in building a space station and the technologies that will ensure that its construction will go smoothly. That makes us very confident that Gateway will happen and that it will work.’’
The key component of the Gateway mission will be the Orion capsule now being built by space engineers. It is designed to take a crew of four people beyond Earth’s orbit and into deep space. Orion’s first manned flight is scheduled to take place by 2023. Once in operation, capsules will be blasted into space on the US’ new generation of highpowered rockets, the Space Launch System, which is designed to send heavy payloads towards the moon and planets. SLS rockets will also transport the modules that will be assembled to form Gateway in lunar orbit.
These will be based on the modules — such as ESA’s Columbus module — that hold stores, contain research equipment and provide sleeping accommodation for crew now working on the ISS.
Last month, Nasa announced Gateway would be fitted with two modules to house astronauts, one to be provided by the US and the other by Nasa’s international partners. — Guardian News and Media