The experts agree: people will go to Mars
Physicists and astronauts come to together to discuss the prospects for settling on the Red Planet. Brian W Pulling reports.
A four-minute film titled A Trip to Mars was released in 1910. It was the first film to depict humans travelling to another planet. In it, a professor finds magic dust which allows him to float to Mars, there to encounter violent trees.
Since then, the Red Planet has been the subject of a constant stream of science fiction books and films, the most recent, arguably, being the successful movie adaptation of Andy Weir’s book The Martian.
But science fiction sometimes presages science fact, and on March 24, in a unique event, an international panel of scientists and astronauts will gather in the Australian city of Brisbane to discuss the challenges of long-distance space travel.
And it is clear that there is robust agreement on at least one point. It’s not a question of if humans will visit Mars, but when.
Rovers and landers have phenomenally expanded the understanding of life, or the lack thereof, on the planet's surface. This year saw the breakdown of the Opportunity rover, which had roamed and studied it for almost 15 years. Last year saw the arrival of a lander called InSight, and the continued development of new crewed space travel capability.
As the ability to shake off Earth’s gravitational hold grows more and more confident, and living in space becomes more hospitable, the limitations preventing interplanetary travel are fewer each year.
Exploration is in humanity’s nature. Andy Thomas, the first Australian astronaut in space, is clear in his support for sending people to Mars.
“There is one reason, and to my mind one reason alone, to take the risk of sending humans to Mars, and that is the search for evidence that life may have once formed there in ancient times,” he says.
“The discovery that life had also started on a second planet in our early solar system would be a crowning achievement of human intellectual enquiry. It would give us, for the first time, an honest assessment of our place in the universe.
“It would profoundly and constructively impact our society, our philosophy and our religions. I can think of few discoveries more important to us all.”
Christine Charles’ work in particle physics is likely to play a key role in facilitating communication between our planet and new colonies. Charles heads up the Space Plasma, Power and Propulsion laboratory at the Australian National University. Her work in propulsion systems is essential for interplanetary travel.
“Gas coming from a jet engine has an exit velocity of around 300 metres per second,” she explains.
“But we can apply strong electric fields to the plasma to pull the positive ions out with an exit velocity of 30 kilometres per second.”
She describes this effect – which is essentially 30 times faster and lasts 30 times longer than the output achieved by traditional systems – as “the interstellar protein bar”.
“Using our experience of 30 years we are developing micro-thrusters that can be used on tiny Cubesats that are only 10 centimetres cube and weigh one kilogram,” she says.
“Our tiny thrusters will be used on communication satellites to help transfer messages from the Earth colony on Mars to large interplanetary communication satellites to communicate with home base on the Earth.”
She notes that “plasma power can be used to get humans to Mars, but it would require a small nuclear reactor to power the plasma thruster”. She acknowledges that there are risks with this method if craft are launched from within Earth’s atmosphere.
Yvonne Cagle is an American physician and astronaut. Her work at NASA involves “generating a fully self-contained closed-loop regenerative life support system for space exploration and planetary habitation that also preserves the human muscle and bone and is radio-protective”.
The level of detail required in identifying and preparing for human survival on a planet with no atmosphere, no food, little water, and a climate only occasionally resembling the harshest night in Antarctica, is truly staggering.
In preparing for these conditions, Cagle described the most interesting recent scientific development.
“Quantum mechanics and the phenomenon of ‘entanglements’ that exhibits how atoms and particles separated at a great distance can influence each other,” she says.
“Quantum theory, as such, has the additional potential to generate countless advances across multiple industries from medicine and more precise magnetic resonance imaging, to communications and more secure encoding, to transportation, including space and a more precise GPS.”
In The Martian, Mark Watney is a botanist, stranded on the planet after his crew is forced to abandon their habitat during a severe storm. Data from rovers has shown how perilous these planet-wide dust storms can be. By relying on sheer force of will to grow potatoes in the barren Martian soil, for example, the character takes readers through many of the challenges astronauts will need to overcome in order to survive until he can be rescued.
Both the novel and the film were very well received, but US physicist, string theorist and best selling author Brian Greene notes that they got one detail glaringly wrong.
“The initial explorers will know they’re going on a one-way journey,” he says. “It’s an amazing commitment to exploration and human kind.”
Greene is the reason so many Mars-savvy experts are about to gather in one room – and in front of an audience.
The discussion, titled We Will Be Martians, is part of the annual World Science Festival, of which Greene is co-founder.
He is keen, like everyone else involved, to one day see humans land on Mars, but adds that the motivation for establishing what would be humanity’s first off-world settlement is important.
There are many possible reasons for setting foot on the planet, but doing so to shift humanity away from Earth to avoid the consequences of anthropogenic climate change should not be one of them.
“To solve a problem by running from a problem is not a solution,” he says.