How Dangerous is Deep Space Travel?

How Dangerous is Deep Space Travel?

Space travel within our own solar system is dangerous enough. So how could we ever survive the vast interstellar wilderness? It would be a risky venture, but one day, we might want - even need - to explore far-flung worlds around other stars. What problems would these brave pioneers encounter on the way? What catastrophes would they need to prepare themselves for? How unforgiving REALLY is the great unknown?

When you get down to it, the equipment standing between astronauts and certain death might be the most worryingly fragile of all. We can’t test structures and devices on Earth to the same limits they’ll be pushed to in deep space, nor can we realistically account for every potential systems failure. Yet malfunctions are bound to happen, and in many cases, astronauts will have limited time and resources to conduct repairs. There’s also the problem of duration. A deep space journey is going to last for years, even decades or lifetimes; eventually, the crew might run out of material or spare parts. Not to mention that even bringing spare parts will be an impediment due to the extra weight.

Out in deep space there’s no potential for resupply, so interstellar travellers will be left on their own in the face of overwhelming odds. In the worst case scenarios, the power, oxygen, or navigational systems might fail, or the craft could collide with an object in space. Many such issues are insidious and next to impossible to avoid in the long-term, such as the system failures that result from “tin whiskers” – a name for microscopic flaws that appear in metals commonly used in circuitry. These “whiskers” can make apparatus fail unpredictably and have previously caused mass recalls of pacemakers.

When something goes wrong, there’ll also be the issue of communication. There’s already a lag between communication systems on Earth and Mars, a problem that will only be amplified in deep space - leaving the passengers detached from mission control in emergencies. The obstacles to communication also mean that there might not be any adequate way for us to keep tabs on deep space missions to know how they fared, or what to do to improve subsequent ventures. A deep space voyage could mean sending people to fend for themselves in the most hostile environment imaginable, with the possibility of never hearing back from them again.

These are all technological problems, ones which – given the time and resources – we can hopefully address before we start launching actual human beings into the ether. Ultimately though, it’s the astronauts themselves who might suffer the largest failures of all, in terms of their health. It’s unavoidable that people will get sick, even in space where bacteria and pathogens aren’t present . . . although it’s worth noting that one of the most bizarre health threats astronauts face could come from fungus. “Aspergillus fumigatus” is found in abundance on Earth, and is responsible for the majority of fungal infections. As experiments aboard the International Space Station have shown, it also grows well in spacecraft, putting everyone at risk of a sudden disease outbreak if they don’t meticulously clean every nook and cranny.

Other diseases, for example, cancer, can occur in anybody regardless of how at-risk they’re deemed to be. And not having the gravity of Earth can result in bone and muscle deterioration, especially over longer periods of time. Our hypothetical crew of deep space travellers would need at least one fully qualified doctor on board, perhaps even an actual surgeon, and more than one to be safe. There’d still be limited access to the type of medication or treatment a sick astronaut could need, and possibly no way to return to Earth – no matter how necessary it became.

On top of physical health problems there are also mental health problems; astronauts are rigorously screened and assessed to determine whether they’re fit to go to space, but testing if somebody is capable of spending decades in that kind of isolation is something we can’t really do, meaning mental problems could arise seemingly out of nowhere. Trapped in outer space with no possibility of returning home, it’s not hard to believe that cabin fever would strike and cause people to simply lose their minds.

But what if there was a way of avoiding all of these dangers, of cutting down the amount of waking time in space, and even making it possible for these deep space explorers to come home again? Well, science-fiction has long had an answer for that: cryonics. Films like “Alien” or “2001: A Space Odyssey” have opted to put the computers in control while the humans passengers are in a cryonic based hypersleep as a way to cut down on perceived journey-times. However, putting humans into stasis is nowhere near as easy as it seems in the movies – as few things ever are. While there’s some research supporting the idea that it might someday be achievable, it comes with its own set of risks: for one thing, we are currently incapable of waking anybody up who has been cryogenically frozen, and it’s also illegal to cryogenically freeze anybody who isn’t already dead.

However, there is the potential that humans might be able to one day enter a state called “torpor”, which is the same state animals go into when they hibernate. This is quite different from just sleeping, as bodily functions are slowed to a crawl to enable these animals to survive without needing to eat or drink for months on end. Potentially, humans could enter hibernation – not full-on hypersleep – by cooling down their bodies, just like a bear would, which would be an enormous help on long-haul journeys through or out of the solar system. It would also be much easier to wake somebody up from torpor in case they needed to go fix something, without having to depend on advanced computers the likes of which we have yet to develop.

Finally, there’s one last tremendous danger the universe poses: radiation. Without the protection of the atmosphere, anyone in space is subjected to a barrage of solar energetic particles from our Sun, and to galactic cosmic rays. Leaving Earth means allowing yourself to be bombarded with radiation, which sadly will damage and kill you rather than giving you any cool or useful mutations. We would need new, lightweight but effective shielding material for deep space travel, but it would still degrade over time and need to be replaced. The danger radiation poses is so great that cancer might be inevitable for deep space astronauts, meaning that a professional oncologist might have to be part of the crew. Researchers have made some headway into developing a drug that might prevent damage to memory functions caused by radiation, but a lot more work needs to be done before we can protect astronauts on long journeys.

Space travel has always been perilous, and there are plenty more dangers lurking out there that we might not even be aware of yet. Conquering our own vast universe, even simply in terms of fully understanding it, is a feat that may well be insurmountable, so it’s clear that the dangers of deep space travel will never be eliminated. Still, there are bound to be people in the future who’ll risk anything to glimpse new worlds beyond our solar system - so hopefully where there’s a will, there’ll also be a way.