There is now broad consensus that we (the human species) are using the resources of our planet Earth at a rate vastly exceeding that which is sustainable in the medium, let alone long term. Various studies have put the current rate of resource utilisation at between ‘one and a half’ and ‘two and a half’ times the Earth’s sustainable capacity, compared to 70% of its sustainable capacity in 1961; and this is without the substantial increases that are forecast as the emerging economies of China and India develop.

Clearly, not just the Earth’s environment is threatened, but so is the very survival of the human species, whether from the many impacts of climate change - of which there is evidence that the rate is already far outstripping the predictions of current models, a nuclear holocaust; an asteroid hitting the planet, or a genetically engineered or mutated virus, there is a real risk that the human species will be the dinosaurs of our era. Of course, even if humanity does survive these shorter-term dangers, life on Earth will not emerge from the red giant phase of the Sun’s evolutionary path – but fortunately - this will not happen for several billion years.

This naturally leads to a discussion of the options for the survival of the human species beyond Earth, that is not to say that every effort should not be made to reverse the impacts of humans on our planet, rather, that there is no guarantee that there is either the concerted will, or the technology, to do so in a viable timeframe; therefore, the survival of the human species may rest on moons and planets in our, and potentially distant star systems. Further, even if we do not believe there is an imperative to colonise other planets or moons to ensure our survival; almost certainly the desire to explore, know and understand our universe will lead to such an undertaking.

Technologically, this is an enormous challenge; in the Solar System there are no planets or moons that could support human life without “terraforming” the environment to one that could sustain water in its liquid state; therefore, colonising the most likely contenders - our Moon, the planet Mars, or Saturn’s Moon – Titan
would all require engineering on a global scale.

Outside of the Solar System the nearest star observed to have a planetary system is Lalande 21185 in the constellation of Ursa Major, at a distance of some 8.3 light years. The next nearest is Epsilon Eridini in the constellation of Eridanus at a distance of ~ 10.5 light years.

Whilst the closest known planet likely to have an environment similar to Earth (that is, it is located in the so-called “Goldilocks” zone where water exists in the liquid state – neither too hot nor too cold!) is Gliese 581d.

This planet was discovered in 2007 and is ~ 20.4 light years from Earth. At the speed we went to the Moon (which was approximately 40,000/kmh) this would be a journey of some 550,000 years; which to put some perspective on this, is twice the time modern humans have inhabited Earth! Therefore, we would need to travel at 10,000 times this speed just to make the journey in one human life span. Not only do we not currently have propulsion technologies that can achieve this, but the life support requirements for a substantial number of human “colonists” over this time period would make the size of any space platform well outside anything feasible in the foreseeable future.

Moreover, the energy required to accelerate a vehicle with finite mass up to speeds close to that of light rapidly approaches infinity as this limiting speed is approached; in fact, Einstein’s 1905 theory of special relativity, which deals with objects moving at very fast speeds, leads to the conclusion that due to increasing mass and the consequential increase in the energy required to accelerate this mass, the upper limit of space flight is unlikely to ever exceed 20 to 40% of the speed of light. Therefore, in the absence of any evidence of “wormholes”, travel across galaxies in a fraction of a human lifespan is still very much in the realm of science fiction.

However, there are other options. Many would argue that all that differentiates humans from other life forms is our self awareness or consciousness; therefore, with modern advances in silicon processors, it is likely that using such technologies as Spiking Neural Networks we will be able to create artificial conscious beings within the next decade or two. But is this enough, is the ability of our central processor really what it is to be human; is this ensuring the survival of the human species, or just some grotesque image of humanity? If we are happy with a robotic solution, then there is no need to travel beyond Earth, as we could engineer robots with artificial consciousness that could survive in any likely Earth environment.

If on the other hand, we choose to invest in the survival of humans in the form we currently understand that to be, there may still be options. The most technically feasible, within the current state of the art, is to consider breeding generations of humans on the space platform to overcome the limitation the human lifespan places on the distances and times involved; perhaps even with some form of artificially slowed ageing, or the use of hibernation; which it is believed may be a latent ability in all mammals, and is currently the subject of considerable research for its application in medical science and space travel.

However, there are enormous challenges here in terms of supplying food, water and an environment in which humans can survive for perhaps several hundred years; let alone the issues of exposure to solar radiation for prolonged periods. Further, it is hard to imagine that anyone would volunteer to spend a lifetime encased in a spaceship, for the sole purpose of breeding further generations, who themselves would be subjected to a similarly sterile existence, and without any say in the matter.

Nonetheless, there is another option, one that is ethically challenging, but (in the medium term at least) technically more feasible than travel beyond the speed of light, or a space platform large enough to support generations of humans, over perhaps hundreds or thousands of years, and the one which this session will explore in more detail.

Imagine a fleet of space platforms travelling at speeds in excess of what would be possible if they had to accommodate living humans; each of these platforms carrying a bank of frozen embryos and sophisticated enough to artificially analyse the environment of their particular target planet as they approach. Only then, if all of the signs are positive, these platforms would artificially birth, nurture and educate a pre determined number of the embryos - humans that would form the first generation of colonists on the new planet.

Colonists, that in order to ensure the ongoing survival of the colony, would have a huge bank of DNA material to create the plant and other life forms necessary. This is not the stuff of science fiction - work is already underway in the development of artificial wombs, most notably that of Dr. Hung-Ching Liu, at the Center for Reproductive Medicine and Infertility at Cornell University in New York; and we are perhaps only 50 years from realising this capability.

Therefore, if we assume that the development and launch of such space platforms is technically feasible; and noting that we don’t have to solve all of the technical problems by launch; since as long as we get the basic building blocks right, with radio waves travelling at the speed of light we will be able update the software for perhaps the first 400 years of a 500 year journey, then consider just some of the other issues involved with pursuing such an endeavour: should we consider the “relatively” close planets and moons in the Solar System, noting the challenges of vastly different atmospheres and environments to that of Earth, or should we look to the distant planets mentioned earlier?

How would artificially nurtured humans develop, would they be human as we know it; what of the ethics of sending frozen embryos and the resulting artificially nurtured humans to an unknown future, is it the ethics of today or the ethics at the time of their birth 400 - 500 years hence that matters; what of the physiological challenges facing the developing humans in a physically restricted environment; should we genetically select the embryos to minimise violent behavioural traits, and at the same time select for the highest intellects; and what, if anything, has religion and spirituality got to say about such missions?

Welcome to “Beyond the Planet”