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Bristol, United Kingdom - Fifty years after the first man in space, Soviet cosmonaut Yuri Gagarin, and the first orbital spaceflight, US astronaut John Glenn, many are asking: "What's next for mankind in space?" In five decades of incredible discovery, we've sent man to the Moon and now have a handful of spacemen living on the International Space Station, orbiting 200 miles over our heads. Our technological prowess seems to know no bounds and we have the ability to mount a deep-space manned mission right now.
But for many, the advances aren't happening fast enough - shouldn't we have a base on the moon by now? That was, after all, the logical step after the Kennedy administration set the task to race the Soviets to the lunar surface in the 1960's. Why haven't we sent a man to Mars yet? It seems puzzling that the majority of robotic missions we send to the Red Planet have a component intended to reconnoiter for a "future" manned mission that never seems to come.
It may seem a shame, then, that we know we can live in space, we know that we send robotic probes to any corner of our Solar System, and yet since the trailblazing Apollo Era of the late 60s and early 70s, no human has ventured beyond low-Earth orbit. Perhaps our evolution into a true space faring species will take longer than a few decades; or even centuries? Let's just hope we don't destroy ourselves through war or ecological decimation before our stellar dreams become a reality.
From interplanetary to interstellar
As a species, we think big. Regardless of whether or not we have the financial backing or the political will to actually do big things in space, there are many scientists, engineers and futurists who know that (assuming infinite resources) we wouldn't only have colonies on the Moon, Mars and beyond; within a few decades we will even have the technological capacity to send mankind to another star.
You may think this is pure science fiction; after all, we can't even find the gumption to send astronauts beyond our own cosmic backyard! But the US defence research agency DARPA and space agency NASA have teamed up, pooled together $500,000 and sent a message to the biggest thinkers on the planet: Come up with a plan for a 100 year mission to a nearby star and we will give you the cash to further develop your idea.
Known as the 100 Year Starship programme (100YSS), the idea is to design the mission profile of a human mission into interstellar space. Sadly, the groups vying for the $500K prize cannot assume anti-gravity will be discovered or the warp drive will be designed in the next few decades. They have to work with the technology we currently have to plan an interstellar mission that could be accomplished within the next 100 years.
Needless to say, the challenge is formidable. But interestingly, the biggest challenge faced by a manned interstellar mission probably won't be technological.
The technology factor
Designing the concept for a robotic (not manned) mission into interstellar space is being tackled by Icarus Interstellar Inc, a non-profit group of scientists and engineers that are working on an ambitious five-year study to develop a starship capable of voyaging to another star (Icarus is also a 100YSS contender). But, like the 100YSS, they have strict guidelines. For a start, they can only assume the use of technology that would be plausible today - once again, for this project, forget the USS Enterprise, that's just not feasible. Also, to maintain mankind's attention span, they have a very tight deadline to adhere to.
In an effort to send an unmanned probe to another star - such as Proxima Centauri, a red dwarf star around four light-years from Earth - Icarus Interstellar aims to bridge that gap in 50 years or less. That means that people on Earth alive during the launch of an Icarus starship will be alive to see it reach an alien star system. This will also be in international effort; a means of bringing humanity together for one collaborative interstellar voyage of discovery and unity. It will represent humanity, not some archaic nation, agency or corporation - things that matter little beyond the surface of the tiny speck of sand called Earth.
"[Voyager 1] has been blazing through space at 38,000 miles per hour, and after 30 years of travel it's only just leaving the outermost reaches of our Solar System."
Keeping in mind that interstellar space is incredibly vast; the Icarus starship would need to be incredibly fast. The fastest moving and most distant manmade object is NASA's Voyager 1. The robotic probe has been blazing through space at 38,000 miles per hour, and after 30 years of travel it's only just leaving the outermost reaches of our Solar System. Going at that speed, it wouldn't reach another star for 100,000 years! So, some clever ways to propel a starship would be required.
The leading method of propulsion considered by the Icarus team is a fusion drive. Though this may sound fanciful, assuming such a mission had the funds, we have the technology to build one. And the best news? Such a means of propulsion could power a starship over 10 per cent the speed of light - suddenly a 50 year timeframe seems plausible (for more on the Icarus propulsion method, see: "Using Fusion to Propel an Interstellar Probe," Discovery News, April 5, 2011).
So, solutions are being found for seemingly insurmountable problems. Novel techniques behind propulsion, communications and navigation are all being developed. There's no doubt that there will be technological hurdles, but like in the 1960s when President Kennedy set the task to get a US astronaut to the Moon by the end of the decade, scientists and engineers confronted the technological issues and found solutions. But Apollo cost a lot of money and required a lot of resources - an Icarus starship would need global backing before it even left the drawing board.
The human factor
So far we've primarily focused on a robotic interstellar probe. The 100 Year Starship will carry humans. So forget technology for the moment, probably the most fascinating component of a manned interstellar effort would be that it is a human endeavour. If we were to build a starship capable of sending humans to another star, some huge unknowns are thrown into the mix.
Assuming the "crew" of the starship took 50 years to reach another star. This is the best case scenario. In this case, the crew wouldn't be astronauts in the modern sense, they'd be colonists; a collection of individuals who would live out their lives inside a spaceship. It would be a one-way trip; no return to the ever receding "pale blue dot" that used to be home.
In comparison, a 6-month mission on board the space station would seem like kindergarten. These interstellar colonists would need to be a society, where all the things we do here on Earth will need to be replicated on the starship. These would be a new people, much like the first European settlers of the Americas; they'd be pioneers with their own sense of purpose. There would be politics and culture. Everything this interstellar community would ever need would have to be provided by the starship.
Mission planners would also need to consider the most basic of human requirements. Assuming they would still be "human" and not some kind of human-cyborg mix (a scenario that cannot be considered as, once again, that is science fiction), reproduction would need to be as "normal" as it is here on Earth. The society would need to be replenished so their mission can be completed. The ever popular topic of "space sex" would be critical to the success to this interstellar race. Therefore, what about inbreeding? There would need to be considerations for the gene pool - too small and huge problems with genetic disorders would present themselves.
Also, there's the question of ethics. For a baby born in deep interstellar space, what human rights would they have? Every facet of society would be focused on the success of the interstellar journey - interstellar babies would therefore be forced into this mission whether they liked it or not.
And what about social breakdown? Say if an extreme political group took control? What if they decided, a few decades into the interstellar voyage, that they wanted to change course? Mission planners may foresee this problem and decide to make the starship pilotless. Perhaps an automated starship with a single mission - to deliver its cargo (humans) to an alien star system - would be their only option.
What about disease? What about cultural differences? As it's a mission of humanity, would there be as many different nationalities and religions represented? This may seed a culture of understanding and peace, but there are few examples when humanity has been successful in doing this.
In short, the most acute challenges of an interstellar mission probably won't be technological; they will be human factors and sadly, they will also be the most unpredictable.
Ian O'Neill is Space Science Producer for Discovery News. He is also the founder and editor of space blog Astroengine.
Follow him on Twitter: @astroengine
The views expressed in this article are the author's own and do not necessarily reflect Al Jazeera's editorial policy.