From going where no one has gone before, to boldly going back to a place from which few have returned
When U.S. President John F. Kennedy set the goal of sending and safely returning astronauts from the moon within a decade, people believed the timeframe to be overly ambitious. When it was achieved on July 20 1969, humans became an inter-terrestrial species, “one giant leap for mankind” as dubbed by Neil Armstrong.
Humankind has its sights set on visiting our neighbour Mars, but faces several, much more difficult milestones in order to make it there. NASA’s Apollo 11 mission took about three days to reach its destination and could carry enough fuel and equipment to make the return trip eight days after its launch. Mars is an exponentially more complicated mission. If travelling to Mars is like crossing an ocean, the Moon by comparison was like reaching an island just offshore.
Space agencies around the world seem to have reignited their ambitions to send people to both the Moon and Mars. Russia’s Roscosmos Energia and the European Space Agency (ESA) have their sights set on going back to the Moon by 2030. Russia wants to put a lander on the surface by 2024, followed with a manned mission for 2029.
Space exploration has been an anomaly when it comes to international cooperation, in which nations have been able to rise above political divisions and technological secrecy concerns. The ESA is likely to cooperate with and join Roscosmos Energia’s mission to the south pole of the Moon.
This past week NASA held a three-day conference in Houston discussing potential landing sites on the red planet. Sites were looked at based on the topographical ability to land, as well in terms of sites of research interest identified by satellites, probes and rovers. One thing to understand is that with the equipment that will make the journey, astronauts likely won’t have the ability to travel long distances.
NASA believes that the first human on Mars is achievable by the 2030s, but there are many obstacles to overcome before then. That does not mean that those challenges are unknown, nor does it mean that NASA and others (including the private sector) aren’t working on their solutions.
The first challenge involves escaping Earth’s own gravity with enough fuel and supplies to make the trip. Konstantin Tsiolkovsky first defined the “rocket equation” in 1903, a three variable equation where any combination of two of the variables limits the third. In this case, knowing the distance we want to travel and the energy thrust that can be generated limits the mass of the rocket we have to use. Most simply, you have distance (to the edge of the earth’s atmosphere upwards and the lateral distance to get up that high), speed (escape velocity of Earth’s gravity at 11.2 km/second) and mass (whatever you’re trying to get off the planet). This is why the rockets used in the space program are absolutely huge, most of the whole payload being fuel, another reason why the missions try to minimize the weight of their equipment, and even why you get those launch stages where parts are shed from the rocket as it reaches higher altitude. So much of the fuel is there just to lift the weight of the fuel to be burnt later, so trying to scale up the amount of fuel that reaches beyond orbit takes much more fuel to burn to get it there. So with the trip to Mars we’re going to need a lot more fuel, equipment and supplies to house and sustain human life once we get there. That also means a lot of money too, given it costs approximately $10,000 per pound of payload into orbit, according to NASA.
So let’s assume we can get a vehicle with everything we need for the trip and life after landing into orbit (either all at once or in pieces for construction in space or at its destination). Next we have to get humans there alive. The trip is estimated to be more than 10 months of space travel (one way), and once we get outside 56,000 km away from Earth, we lose its magnetosphere protection from radiation. This radiation would hinder cognitive function and/or eventually kill humans. Mars does not have a magnetosphere, which may be a reason why we have not discovered complex life forms there, let alone any microbial life.
Not only that, but astronauts would be experiencing isolation and very little physical mobility for lengths of time previously unknown to our species. In August six people began a year-long experiment in isolation conducted by NASA in Hawaii to simulate prolonged living on the Martian surface. In 2014, NASA conducted experiments where subjects had to stay in bed for 70 days to see the physical effects of relative immobility. Following the 70 days, no subject was able to stand for 15 minutes after getting up due to the blood volume lost during their bed-rest and changes to their cardiovascular systems. The lack of gravity in space also leads to bone density loss, a major reason for why astronauts on the International Space Station have daily exercise regiments while in space.
Setting down a landing craft on Mars is much more difficult than on the Moon, or on Earth for that matter. The Moon had no atmosphere to resist a craft’s descent so it could go straight down. Earth’s atmosphere was thick enough that it could slow down the craft through friction, allowing capsules to parachute into the ocean in the early days, or more recently, allow the space shuttle to use its engines to fly before landing.
One of the more interesting challenges, particularly as it relates to research, is biological contamination. When Armstrong, Buzz Aldrin and Michael Collins first returned from the Moon, they were quarantined for three weeks in case they brought back any bacteria or diseases foreign to Earth. With water detected on Mars, the likelihood of bacterial life is greater than that on the Moon. But contamination concerns are two-fold – it’s not about what humans may be exposed to on Mars, but what humans (and any Earth-made equipment) would bring with them to the Martian environment. Any equipment we have sent to Mars undergoes extensive efforts to make sure biological materials or bacteria does not stow away for the inter-planetary ride. NASA has policies, procedures and personnel for just this purpose. Why it’s important pertains to the biological and ecological research we would like to conduct on Mars. Questions we hope this research will answer includes whether any Martian life resembles life on Earth (e.g. DNA), and if there’s any life there at all that hasn’t been fried by radiation. If we went there without these precautions, any life found there could have been tainted by our own presence. There is bacteria that can survive inter-planetary travel, which may represent how life formed on Earth. In 2011, a set of drill bits on the Mars Curiosity rover deviated from NASA’s decontamination procedures – something NASA does not want repeated.
It feels as though we are looking to the stars once more with purpose and ambition, and not just wonder.
The Brock Press