Friday, 1 March 2019

The Ice Billionaires

One day, when the human population away from Earth reaches a certain level, new economies will emerge, ones that are almost completely independent of our home planet. And not long after that the new economies' first Earth-independent billionaires will emerge. But what service or product will generate such wealth?

Providing construction material will be one way. Finding enough suitable material to construct human settlements, whether in space or on the surface of a moon or planet, is a difficult and awkward task. It would not be long before businesses are created that specialise in mining and distributing such material. The most successful will enjoy an ever-increasing demand for their materials as colonies expand and new colonies are started.

Another profitable service would be transportation. There will be a constant need to transport people and cargo of all kinds around the Solar-System. Businesses will be set up to provide reliable and regular transport services. Eventually huge spacecraft with the capability to move millions of tonnes of cargo, and hundreds of passengers, will be making journeys between the mining facilities and the colonies and outposts. Leaving Earth to work at one of the colonies for a few years, and then returning home or moving on to a different colony will become a relatively routine, if still lengthy, process. The large interplanetary ships will at least provide a high level of comfort and simulated gravity, which will be much healthier and safer than what we could provide travellers at the moment.

A typical mid-sized cargo ship. As well as cargo carrying ability, this ship has a large crew and passenger section which rotates to provide artificial gravity. Eventually there would be thousands of such spacecraft, some much larger, providing cargo and passenger transport between the colonies and mining facilities, and of course Earth.

But there is one product that will create the most riches for the people that set up businesses to mine and deliver it. That product is ice, and especially water ice.

There is a relative abundance of water ice in the Solar-System. Even Mercury, the closest planet to the sun, has water ice preserved in craters that are in permanent shadow.  There are many ice moons around Jupiter, Saturn, Uranus and Neptune, and Saturn's rings are 90 percent water ice. And then there are the Kuiper Belt objects beyond Neptune, which are mainly composed of ices, including water ice. And beyond that in the far reaches of the Solar-System, on the border with interstellar space, there is the Oort Cloud which is the source of many of the comets that periodically make their way into the inner Solar-System. It's likely to contain enough ice equivalent to several times the mass of Earth.

I expect the ice industry will be split into two: with one part specialising in ice mined on a planet or moon's surface and with it's customer base restricted to the body on which it was mined (due to the cost of transporting it out of the local gravity well), and the other part dealing with ice mined on asteroids, comets and other small bodies. Such ice will be easily transported to space-born colonies and orbital facilities, and to the small rocky worlds such as the inner Solar-System asteroids, and the moons of Mars: Phobos and Deimos. Those bodies will certainly have human activity on them as materials for construction are mined. Their demand for water ice will be high.

Surface-Bound Ice Mining

In the higher latitudes of Mars, close to the planet's north polar ice cap, lies the Korolev Crater: an almost 82 kilometre-wide impact crater filled with water ice. The base of the crater is more than two kilometres below the rim, creating a cold air trap that's allowed the crater to fill up with the ice to a depth of 1.8 kilometres.

Korolev Crater: An ideal location for a large human colony due to the vast amount of water ice contained within its rim. The first ice mining business is likely to be set up here. It will be the start of what will become a global corporation supplying essential ice to the entire planet.

The crater's location close to the polar ice cap, and just south of the expansive dune-filled region known as Olympia Undae, and it's abundance of water ice, makes it an ideal location for a large human colony, and the best example of a massive and conveniently located source of water. The area surrounding the crater will be relatively easy to traverse, making the construction of roads towards the north pole, and south towards the equatorial regions, straightforward. It is the most likely location for the first of the planet-bound ice mining businesses to be set up.

The person who will become the very first ice billionaire may well be living on the rim of the Korolev crater in several decades time just as material self-sufficiency from Earth is achieved. His or her vision and drive will enable the rapid expansion of the colonies on Mars, and become the inspiration for others elsewhere on the planet and far beyond.

The crater could well become the site of several sizeable towns, even cities, whose inhabitants are specialised in mining water ice. The towns would be located on the rim of the crater. Access in to the crater will be easy as the slopes are gentle and natural routes for roads would be easy to find.

A close-up of part of the Korolev crater's rim, which is typical of where most of the human settlements will be located. Roads will be built down into the crater to provide easy access to the ice mining facilities. Roads will also be needed that head out of the crater to allow exploration of the areas beyond, and for transporting the ice south to the settlements in the equatorial regions.

The ice mining business's first contracts will be with Earth governments as they hand over the extraction of the ice to a private venture, but within decades, as the colonies themselves separate from direct Earth control and become truly independent, the contracts will be with Mars governments, and with other business sectors that have developed on the planet. By that time ice mining will have expanded to the north and south poles. It will be an efficient global industry that will allow millions of humans to live and thrive on the planet.

The same is likely to happen on other worlds that are suitable for human colonisation, with Saturn's moon Titan a prime example. There will be differences, of course. Mining anywhere on Titan, and the other ice moons will result in plenty of water ice being found. Many more smaller competing businesses are likely, which will ultimately merge to become a handful of large corporations.

Interplanetary Ice Mining

Space-bound colonies, either in orbit around planets, moons or the sun, will become a significant presence in the Solar-System once human colonisation away from Earth becomes established. They will be constructed from material mined from asteroids and most likely constructed in the asteroid belt (or from the Trojan asteroids that share Jupiter's orbit) and transported to their ultimate destination once complete. Such structures, each built to house thousands of people and to be as independent and self-sufficient as possible, will still need regular deliveries of water ice (and other volatiles). There will be no shortage of people ready to exploit that need, and the earning potential it represents.

Transporting water up from the surface of planets and the larger moons will be difficult and very expensive, due mainly to the effort and energy required to get millions of tonnes of ice out of such deep gravity wells. Such efforts would be foolish to attempt, and could never be considered as a viable business plan.

For such space-bound colonies the efficient solution is to mine the ice from small objects with a negligible gravity well, such as Kuiper Belt and Oort Cloud objects.

An artist's impression of the dwarf planet Eris, that resides in the Kuiper Belt. Eris is currently the most massive known Kuiper Belt object. Despite its size (over 2,300 kilometres in diameter) its low gravity of 0.083g would probably be low enough to make the export of ice volatiles viable. Eris could end up being one of the most active and profitable ice mining locations in the outer Solar-System. Image by S M Pritchard.

The objects in the Kuiper Belt, which lies just beyond the orbit of Neptune (and includes dwarf planets such as Pluto, Orcus and Eris), is the most conveniently located of the two. Once there is a human presence in that region mining operations with transport infrastructures will be set up to exploit the abundant ice riches that are available. There will be a regular fleet of cargo ships, largely crew-less, making their way inwards to the large space-bound colonies that are likely to exist around the major planets and moons. Their trajectories will be slow, but very efficient, and their regularity will ensure a constant supply of ice volatiles to a hungry and highly populated inner Solar-System.

A cargo ship prepares to dock with a massive space-bound colony in the inner Solar-System. Such a facility would need a regular supply of ice volatiles, including water ice. Supplies mined from objects in the Kuiper Belt or beyond would arrive at least annually to fulfil the needs of the thousands of colonists. Image by Bryan Versteeg.

Very large space-bound colonies have a distinct advantage over planet-bound colonies: those living there can live with Earth-level gravity, due to the ability to rotate the colony. With a large enough diameter any unpleasant coriolis effects can be eliminated (as the rotations per minute can be kept very low - less than one per minute if the colony's rotating section is 1,000 metres or more in diameter). It is likely that the ice billionaires would chose to live in such facilities due to the obvious space and luxury they could provide.

The interior of a space-bound habitat. With a diameter of hundreds of metres it would be able to rotate at a quite leisurely pace and still create enough artificial gravity to match that of Earth. The interior would be very spacious and would be the preferred home of the future ice billionaires. Image by Bryan Versteeg.

The motivation of the ice billionaires (and those in other industries) to expand their businesses further to increase their own wealth will be an important factor in the speed at which human colonisation spreads further and further away from Earth. Such activity needs to be encouraged. It is one of the ways to ensure that our species will endure if a catastrophe - either natural or of our own making - occurs on our home planet.

This kind of insurance against our extinction is essential. Governments on Earth are too slow, fickle and bureaucratic to provide that insurance any time soon. We need to embrace the commercialisation of space colonisation.

The future entrepreneurs that can exploit the business opportunities in the Solar-System are quite possibly alive as children today. They will one day leave Earth and create the most far-reaching corporations in human history. They will be motivated by profit, but inspired by the innate desire in all of us to survive as individuals and as a species.

Friday, 1 February 2019

A Single Origin of Life

Is all life in the universe related, and from the same single point of origin?

Life is likely to have formed in the universe as soon as the right conditions arose. And that will have been soon after the first supernovae, when the violent deaths of those stars spread out the heavy and complex elements that are considered essential for life to form.

The oldest supernovas studied occurred 10.5 billion years ago, just two billion years after the formation of the universe itself. The planetary systems that formed soon after are likely to be the ones to evolve the first ever life in our universe.

The first supernovae more than 10 billion years ago created the elements essential for life to begin

For life as we know it to survive there needs to be a certain temperature range, plenty of liquid water, and the right mix of gasses. And this state needs to be maintained for hundreds of millions of years or more for anything other than the simplest types of life to form.

How often life begins (abiogenesis) once the conditions are right is unknown. It is possible that as soon as the conditions are right then life emerges. If this is the case then life will have arisen quite often, and is probably flourishing on billions of planets right now. But despite a huge amount of research and experimentation this has not yet been shown to be the case.

It's quite possible that something else is required, something we are yet to identify, that makes the process extremely rare. So rare, in fact, that it has only ever happened once.

If that is the case then the only way life could become widespread is via panspermia: the distribution of life via dust and meteoroids as collision debris is ejected into space, carrying primitive but hardy life with it. Life on Earth could well have arrived this way. It could have been travelling through interstellar space in a dormant state for many millions of years. And the world where it came from could itself have been seeded in such a way.

A procaryote: a simple but hardy life form that can survive in some very extreme conditions. Could such simple archaeal/bacterial life have spread throughout the universe from a single point of origin?

Life on our planet could be descended from life that originated on a planet millions of light-years away, and it could have evolved billions of years before even our sun was born.

Ultimately there could be just one source of life in the universe, formed soon after those first supernovae. All life in the universe, at least all life of the kind that is found on our planet, could be related to that single abiogenetic event.

The only life we know of and have studied is on our planet. The biochemistry of all of life on Earth is carbon-based with water as a solvent and DNA or RNA to define growth, structure and function. But life is theoretically possible with other forms of biochemistry, which would increase quite significantly the number of planets and locations where life could survive. Silicon, like carbon, can create molecules large enough to support biological information, and ammonia or methane are suitable alternative solvents to water.

There is one place in our Solar-System where an alternative kind of life could be present right now: Saturn's moon, Titan.

Saturn's moon, Titan, is the most likely place in the Solar-System where we might find non-Earth-like life, based on methane/ammonia rather than water

This possibility is something that needs investigating (see my previous article 'Human Colony on Titan' where I mention the indigenous life that we could encounter there). It is so cold on Titan that the lakes consist largely of methane rather than water, and the thick atmosphere (thicker than Earth's) provides great protection from cosmic rays and small meteorites. Saturn's magnetosphere also provides some shielding. It is the most likely place for us to find non-Earth-like life in the Solar-System.

Panspermia could also be responsible for life on Titan. If methane-based life is abundant then it too could have arisen around the same time as water-based life and been spread aboard collision debris in the same way. If there is indeed something special and extremely rare that needs to occur for life to form then methane-based life could have a single point of origin in just the same way as water-based life. All life, no matter what biochemical base it has, could be related to a single distant ancestor for that biochemical type, perhaps even in the same star-system that the other forms of life arose. Something very unique could well have occurred there: the event that kick-started life - the spontaneous occurrence of something profound that enabled non-living matter to become life.

Whether or not that is the case could have profound ramifications for our species as we embark on interstellar colonisation. We could find that life is present in most of the star-systems we visit. If so, will it be beneficial, a hindrance, or a danger that's lethal to our species? Or we could find that each and every planet that we visit is barren of life, no matter how Earth-like it appears to be. That could be a good thing, allowing us to colonise suitable planets without having to deal with strange and potentially harmful lifeforms. But it would also mean that we are truly alone.

Earth could end up being that single source of life in the universe.

That is quite a profound thought...

Tuesday, 1 January 2019

Machines Meeting Machines

Most science fiction stories that feature alien encounters or visitations show biological creatures that have traveled vast distances. The more I think about it, and the more I read about it, the more I am convinced that this is unlikely to be the way we will eventually meet an extra-terrestrial intelligence.

Our first encounter with such an intelligence will almost certainly be with a machine.

Most people expect that the first encounter with an extra-terrestrial intelligence will be with a biological being, but this is highly unlikely

But why will that be?

Interstellar travel by biological creatures such as ourselves is difficult, costly, and fraught with danger. The food, water and air that's needed for such a journey has to be provided by the star-ship itself. This requires an incredibly complex and almost perfectly tuned biosphere which will need to function for at least a few centuries, and probably far longer. And the ship will need to be huge if it's to accommodate a large enough population to maintain genetic health and diversity.

Building such a star-ship is not impossible. The technical challenges are in no way insurmountable. But the political, emotional, and even ethical obstacles probably are. The world's governments would have to come together and cooperate to get such a project even started. All the military and economic conflicts would need to be resolved, and all the hate and suspicion of our cultural and religious differences transmuted into something positive, respectful and cooperative. And, of course, the general population (whose taxes would fund the venture) would need a lot of convincing as they and their descendants would not see any personal benefit from it.

It does not take much thought to realise that such cooperation goes against the most basic but intensely powerful instinct of any biological life-form: that of self-preservation. Such an instinct is generally beneficial,  but for an advanced civilisation such as ours it could, on a national scale, easily result in an endless series of territorial and ideological conflicts that consume our time and energy. One day the result of such squabbling is likely to result in another global war that could wipe out our species. It's ironic that the survival instinct that has served us well throughout our primitive history, allowing us to evolve into a creature of such high intelligence, could well end up destroying us completely.

Large interstellar spacecraft capable of supporting humans for generations are unlikely to be built until our territorial, political and religious differences on Earth are resolved

That survival instinct is not going to change. Cooperation between governments is not going to reach anywhere near the levels required to build human-crewed star-ships. But the development of crewless interstellar spacecraft requires no such cooperation. And neither does the development of the advanced artificial intelligence to run it. Individual nations, and even individual corporations, can certainly do that.

Because of this our interstellar exploration will almost certainly be conducted by machines. And those machines will contain within them a sophisticated artificial intelligence; one that is able to function autonomously for centuries. And it will be designed to be our ambassador should an advanced alien civilisation be encountered .

Our first encounter with extra-terrestrial intelligence will be with something artificial , rather than a biological life-form. 

And that will be the same for all intelligent extra-terrestrial civilisations. Highly intelligent machines will do the exploration. And due to the communication problems across the vast distances between star-systems those machines will be designed to deal with first contact situations. They will also be able to utilise the resources in the star-systems they visit, replacing and repairing themselves, and even improving their own design. My earlier article, 'Intelligent Machines Are Watching Earth', discusses the possibility that such machines are observing our planet right now.

Its not hard to imagine them setting up machine colonies and constructing more of their kind that will head off in new directions, greatly speeding up their exploration. New machine civilisations will be created. Entire planets could be engineered to be the new home worlds for such artificial creatures.

The home planet for an intelligent artificial species. Over millennia the entire planet has been engineered to accomodate such a species. It will be a highly efficient and sustainable machine civilisation.

It does seem to me that due to the relative ease of manufacturing and distributing intelligent machines across interstellar space, the most abundant form of intelligent life in the universe (if it can be called life) is artificial.

There will, of course, be some biological beings exploring interstellar space, probably on 'world ships': huge vessels, tens or even hundreds of kilometres in length. But they will be exceptionally rare. Due to basic and irrepressible instincts, almost all advanced biological civilisations will render themselves extinct within a few centuries of developing high technology. But many will have survived long enough to initiate interstellar exploration using intelligent machines. Some of those machines - those that are designed to manufacture copies of themselves and make improvements - will go on to establish themselves in other star-systems. Eons after the biological civilisations that first created them have died out, the machine civilisations will continue to thrive and explore.

One day one of our machines will meet one of those machines.

I hope our biological civilisation is still around to appreciate that moment.

Monday, 1 October 2018

Climate Change - The Point of No Return

We are on the verge of rendering our planet uninhabitable, unless drastic action is taken.

Scientists have recently announced, quite alarmingly, that climate change on our planet could soon reach its tipping point. We are only decades away from that moment. It will happen within a generation.

Lowering our carbon dioxide emissions is no longer enough. Carbon dioxide needs to be extracted from the atmosphere. And we need to start doing that now on a large scale. Otherwise, global warming will enter an unstoppable feedback stage, where warming triggers more warming, which triggers even more warming. Such feedbacks include the release of methane due to the thawing of permafrost, loss of snow cover, the melting of Arctic ice, warming seas, and the loss of forests. All of those will reduce our planet's ability to reflect heat and absorb carbon. The number and intensity of forest fires will increase dramatically, releasing huge amounts of greenhouse gases into the atmosphere. This will only magnify the feedback effect even more.

Global warming will result in an increase in the frequency and ferocity of forest fires. Such fires add vast amounts of greenhouse gases to the atmosphere.

The end result of such warming is not clear, but at best it will significantly limit the areas of the Earth where humans can comfortably survive. At worst it will render the whole planet uninhabitable, water will boil away, and the Earth will suffer the same fate as Venus,

Even the 'best case' scenario will cause massive migrations, and subsequently major wars over dwindling food, water and energy resources. Such wars will only add to the warming feedback. As the desperation of governments increases those with nuclear weapons at their dosposal will eventually use them. Countries such as Israel, India, Pakistan and Iran - all nuclear powers and all located in what will become some of the worst affected regions - will feel compelled to use such weapons as countries to their north attempt to stop the migration of their populations. This will cause tremendous damage to the environment, and render even more areas uninhabitable. And there would be a very high chance that a limited nuclear war would escalate rapidly into a global nuclear conflict.

At that point our current technological civilisation will end, and with it humanity's chances of spreading beyond the Earth to become an interplanetary, and then an interstellar, civilisation. Our ability to preserve our species will have slipped away.

If he climate change wars turn into nuclear conficts they will bring to an end our current technological civilisation. Humans may have a change to develop another advanced civilisation one day, but it is likely to take centuries or even millenia to get back to anything like that which we have achieved today. Without forewarning such a civisation is almost certainly doomed to suffer the same fate as the one before it.

Such a dramatic warming of the atmosphere will cause a rapid rise in sea level, raising it to well over a hundred metres higher than it is at present. In addition to the billions who had already perished in the wars of the previous decades, hundreds of millions more will die. Survivors, who will eventually number just a few tens of million at best, will struggle to live in the few remaining higher altitude lands. Their existence will be basic and medieval. It will be a return to the dark ages. Thousands of years of progress and knowledge will have been lost.

Only then, with the destructive output of our current civilisation at an end, can the climate of Earth have a chance to stabilise. The ice caps will reform and the sea level will reduce. After many centuries flora and fauna will start to recover. Only at that point, humans, if they are not extinct, will have another chance at building a technologically advanced civilisation.

It's unlikely that we can prevent a climate change disaster on our planet, but we can improve on the 'best case' scenario if we start doing three things right now:

1. Preserve Knowledge of our Discoveries and Inventions

We must help survivors in the post-climate change world avoid repeating our calamitous mistakes, and allow them to 'fast-track' through what has taken our current civilisation thousands of years to learn, discover and invent.

A comprehensive record of our achievements (and of our destructive actions, so that mistakes are not repeated), must be preserved in a way that they can understand, and in a way that will last for thousands, even millions, of years. We must investigate how we can provide such knowledge to our distant descendants, and then store it in multiple safe yet easily accessible locations, including locations elsewhere in the Solar-System.

DNA could be the ideal solution to extremely long term information storage

Using paper or digital media to preserve knowledge will only be suitable for a few hundred years or so, but such means should be used initially, as our descendants will be able to understand and use these forms of storage.

But a more radical solution is needed for complex and advanced knowledge that will be useful once any new civilisation progresses to a certain level. Storing information in DNA is one such solution. It's been shown that if the DNA can be kept at sub-zero temperatures the information will maintain its integrity almost indefinitely. DNA information stores would be best located away from Earth, perhaps on the Moon in the permanent darkness of one of the polar craters, and deep within some of the planetary bodies of the outer Solar-System.

2. Work to Avoid or Delay the Climate Change Tipping Point

Even to just delay the tipping point we need to start work now.  The small steps some of us are currently taking are utterly inadequate.

Our civilisation needs to fast track the very widespread use of electric vehicles by banning petrol and diesel engines within a decade. All developed countries need to push this idea hard, and give incentives to developing countries to do the same. And governments need to increase vastly the funding for research into clean energy, and get nuclear fusion working. The generation of electricity by burning coal and oil has to stop on a worldwide scale without delay. Countries like China appear to be increasing the use of fossil fuels for energy generation, which is going to be catastrophic if it is not prevented.

But that alone will not be enough. We need to start undoing the damage we've already done.

Various climate engineering projects should be started immediately. These are possible with current technology. To help reduce global warming solar radiation management needs to be implemented to reduce the sunlight absorbed by the atmosphere. Relatively simple things can be done such as seeding clouds with sea water to brighten them (and therefore reflect more sunlight), and using pale roof colourings and promoting the expansion of polar ice.

Removing carbon dioxide from the atmosphere using facilities such as this is possible. It can be stored in hard pellets which can be buried deep underground.

We need to start removing some of the excess greenhouse gases that our activities have pumped into the atmosphere. This can be done directly using machinery that would then store the extracted carbon dioxide deep underground, and indirectly by promoting natural processes, such as extensive tree planting to reverse deforestation, and ocean fertilisation to add nutrients to the upper oceans to increase carbon dioxide absorption.

And the growth of our human population needs to be controlled, especially in developing countries. We can no longer support such large increases, which are generally located in regions that can least support it. It should be stabilised as soon as possible, and allowed to reduce naturally to a more sustainable level.

Doing all of the above is the best chance the Earth has of remaining a viable place for humans to live. But it is likely to only buy us some time - nothing more. We need to establish our civilisation elsewhere to properly secure our future.

3. Secure the Survival of Our Civilisation Independent of Earth

There's a significant possibility that the feedback warming will not stop, and if that is the case the Earth could indeed end up in a state similar to that of Venus.

The only way to ensure the continuation of our species beyond that event is to make sure that there are self-sustaining human colonies beyond Earth, on planetary bodies such as the Moon, Mars, and especially on what is looking like the best location: Titan, the largest moon of Saturn.

As well as colonies on planetary bodies there should be very large space habitats constructed throughout the Solar-System that would house tens of thousands. The resources to build such massive facilities can be found in the asteroid belt between Mars and Jupiter.

We will have to mine asteroids on a large scale to construct the off-world facilities humans will need to live independently from Earth

Extracting those resources would be relatively easy due to the very low gravity wells of the asteroids. The establishment of mining operations there must be an immediate priority. The space habitats could be constructed in the asteroid belt and then maneuvered into their final positions, either into planetary orbits, or into their own independent orbits around the sun.

In parallel to the development of colonies around the Solar-System there needs to be development of interstellar missions with the goal of establishing human colonies around other stars. More and more exo-planets with the potential for colonisation are being discovered all the time, with one, Proxima Centauri B, only 4.3 light years away.

The planet Proxima B, which orbits Proxima Centauri 4.3 light-years from Earth. It's the closest known Earth-like exo-planet, and has huge potential as a suitable destination for our first interstellar colonisation mission.

It would be a mammoth undertaking, and there are incredible engineering challenges to overcome, but investment in the rapid development of the methods and technology required is essential to build such habitats in time. As well as providing immediate funding, it should be the priority of governments to ensure that education systems are geared to maintain a constant supply of highly capable scientists and engineers to make it a success. The long term survival of our species depends on it.

If all three of the above steps - preservation of our knowledge, delaying or avoiding the tipping point, and establishing large self-sustaining human colonies elsewhere in the Solar-System and beyond - are pursued with the resilience, determination and creativity that our species has in abundance, then we will survive.

But we must start now.

Right now.

Monday, 3 September 2018

Uranus Mission: Essential and Urgent

Of the larger planets in the Solar-System, Jupiter and Saturn, and their moons, seem to get almost all of the attention when it comes to orbiter and lander missions. That's understandable, of course. There's a huge amount of fascinating bodies in those systems, and many mysteries to solve and theories to prove. And the fact that those systems are relatively easy to get to helps.

But a mission dedicated to Uranus and its system of moons is long overdue.

The planet Uranus: the coldest planet in the Solar-System

Since 2010 there have been five proposed missions to Uranus. These have been by the United Kingdom (Uranus Pathfinder), ESA (MUSE and ODINUS) and NASA (Oceanus and NASA Uranus Orbiter and Probe). It’s disappointing that none of them has yet been given the go-ahead, and none of them are likely to be given it due to budget constraints and the priority given to other missions, particularly those to the Jovian system.  Even if one or more of the Uranus missions was given the go-ahead, the earliest any of them would arrive at Uranus would be the mid to late 2030s (with ODINUS not even launching until 2034).

A Uranus orbiter and atmospheric probe

There is clearly the need for much more urgency and ambition. And there is a need to use a means of getting to Uranus that does not require a cruise time of up to 15 years (due the requirement for coventional rocket propulsion to make use of multiple gravitational slingshot maneuvers using Venus, Earth, Jupiter and Saturn). A more advanced method of propulsion is required: one that is much more powerful and sustained than current rocket technology. Nuclear thermal rockets, which have been developed and tested for decades, but never used, would allow for an orbiter mission to be launched on a direct trajectory to Uranus. The journey time would be reduced to just a few years.

But why would there be such an urgency to get an orbiter mission all the way out to Uranus so quickly? It's simply because there are many mysteries about the planet that need answers. And the sooner we know those answers the better.

One of the major mysteries about Uranus is that, unlike the other planets in the Solar-System, it seems to generate almost no heat at all. There seem to be no reasonable explanations as to why. It's quite possible that the heat energy could have been extracted from the planet by some extreme geo-thermal power generator. Indeed, the planet's unusual axial tilt, which makes the planet appear as if it's laying on its side compared to the Solar-System's other planets, and its magnetic field, which is at an extreme tilt in relation to the planet's rotation and is also off-centre by quite a margin, all point to unusual and potentially unnatural events that occurred as the planet's resources were utilised.

There is a likelihood that long ago the Uranian system was the location of some intense activity by an ancient extra-terrestrial civilisation: perhaps from Venus or Mars, or maybe even from Earth many millions of years ago (see my article 'Pre-Human Technology in the Asteroid Belt'). A vast engineering project of some kind may have been implemented. The evidence of such activity, even if it ceased hundreds of millions of years ago, will still be there for us to discover. We need to know what was going on, and why.

The most likely place we'll find that evidence is on the planet's moons.

Miranda, the smallest and innermost of the major moons of Uranus

The moons would provide all the resources needed for a civilisation as it worked. The moon Miranda, the smallest of Uranus' major moons, certainly has the appearance of a moon that has been heavily mined. As it's composition is mainly water ice its surface could have been the main source of water, oxygen and hydrogen for fuel.

The planet's largest moons, Titania and Oberon, do not show signs of mining, but they would make ideal locations for habitats and deserve detailed surface investigations. Ulimately, a strong human presence is required for a thorough investigation (and of course for the more general reason of helping ensure the survival of our species if/when something catastrophic occurs on Earth).

At the very least, a human colony in the Uranian system would be an ideal base from which to explore the outer Solar-System.

Human colonists on Miranda enjoying ultra-low gravity recreational activities 

A small human outpost on Titania, the largest moon of Uranus

An orbiter mission to Uranus and landers for its moons are essential. Sooner rather than later we need to know what happened in the Uranian system. And ultimately we need to establish a permanent human presence there to help ensure our long-term survival.

Friday, 1 June 2018

Human Colony on Titan

Titan is Saturn's largest moon (and the second largest in the Solar-System after Jupiter's moon, Ganymede). It is unique in many ways, most notably for its thick atmosphere, weather patterns, including rain, and its lakes and rivers. It is one of the best places in the Solar-System for a large human colony. It has the potential to support millions, in fact.

And there is, of course, the potential to discover a completely different form of life and biology to that of our own.

Saturn's largest moon, Titan. Left: a true colour image. Right: overlaid with an infra-red view of the surface.

Here's why Titan would be a promising place to build a colony:

  • Titan's thick atmosphere and air pressure, that's just above that of Earth's surface, would eliminate the requirement for bulky pressure suits. A suit would simply need to provide warmth and oxygen.
  • The hydrocarbon lakes would provide the materials to make plastics that could be used to make all the required structures for living and working.
  • The atmosphere would provide excellent protection from radiation and meteorites, and make any leaks or failures of habitats a problem rather than a lethal failure (the indoor and outdoor pressure would be the same and therefore any leaks very slow).
  • Drilling into the surface would provide all the water a colony could ever want. And from that could be extracted oxygen, and hydrogen for fuel.
  • The low gravity would make return to space relatively easy, and the thick atmosphere would make aircraft particularly easy and economical to fly. Human-powered flight is possible.
  • If there is any life on the surface of Titan it is likely to be methane-based, which should mean it would be unable to survive in a human environment. The danger of either life-form infecting the other would be minimal. It's very likely they could coexist without any problems.

There are significant challenges to overcome, but none are in any way insurmountable:

  • The surface temperature is extremely low at about -180 degrees Celsius. This is significantly colder than even the coldest locations on Earth. New types of clothing and insulation will need to be developed to cope with this.
  • It is currently unknown exactly how detrimental to health living in such a low gravity environment would be. Those born and raised on Titan may well be unable to leave the moon due to the weakness of their bodies. They would certainly never be able to visit Earth.
  • The journey time from Earth to Titan would be many years using conventional rocket technology. Unless the ship had a rotating section to generate artificial gravity, and effective radiation protection, the crew would suffer significant health issues. Nuclear propulsion would significantly reduce journey times (this has been researched heavily but never used).
  • There is a possibility of water-based life existing in the subsurface oceans. The water extracted for use by the colonists would need to be thoroughly studied and sterilised to prevent contamination and infection.

A view of Titan's surface from an altitude of 70 kilometres

Creating a Self-Sustaining Colony

Landing on airless moons is always problematic due to the need to rely solely on rockets to slow down enough for a safe landing. A large amount of fuel needs to be transported each time. No such problem exists at Titan. The thick atmosphere and low gravity of the moon makes it easy to take advantage of aerobraking techniques and relatively small parachutes (compared to the large parachutes that would be required in the thin atmosphere of Mars).

Because of this very large landing craft, carrying hundreds of tonnes of cargo, or even hundreds of colonists, should be able to land quite easily.

Before colonists arrive in large numbers a sizeable 'town' of habitats will be needed, with power generation and crop growing facilities to enable self-sufficiency. It needs to be well planned, with plenty of redundancy, factories (making use if the liquid hydrocarbons), and with roads and airstrips, and space launch facilities.  There will be no chance of rescue for a colony so far from Earth.

The initial habitats will have to be sent by unmanned missions. They will be built robotically. The first humans will then arrive to expand the facilities and establish what will become the first self-sustaining colony. It's likely that this initial stage would take two or three decades to complete. Essentially, the first generation of colonists would be living in a frontier town, with limited but slowly improving comforts.

A shuttle takes off for a journey to an orbiting station around Titan. Once the colony matures and fuel and manufacturing factories are established there will be regular trips to and from the moon's surface to other colonies in the Saturnian system.

The second and future generations would benefit from the growing colony, with spacious homes, more recreation time, and a growing system of orbital facilities to support life on the surface including communications, and transit to and from the surface and to other colonies that will no doubt have been established elsewhere in the Saturnian system and beyond.

At this point, when survival is routine rather than the main task of each colonist each day, research and scientific discovery can take priority. And it will no doubt focus on the indigenous life that is quite possibly abundant on the moon. Such life could well be complex, with the lakes especially teeming with larger creatures that are just impossible to detect without a surface presence.

A large methane-based complex life-form living in one of the hydrocarbon seas on Titan. The actual life on Titan is likely to be less extravagant than that shown in this image, but it still could have evolved into an array of sizeable creatures.  

Titan could have a diverse ecosystem, far removed from what we know here on Earth. It is the most exciting location in the Solar-System to look for life. There will be no shortage of scientists willing to live there when the time comes to send them.

Robotic Exploration

Before any human colonisation of Titan can start we need to know much more about the moon and its surface conditions. We must send surface exploration missions there at the earliest opportunity.

Some missions have been proposed since 2008, such as the Titan Saturn System Mission. It's an ambitious proposal consisting of an orbiter, a balloon to explore the atmosphere and photograph the surface, and a lander that would splash down in one of the methane lakes.

Another proposal is the Titan Mare Explorer. It's a relatively low cost mission that would put a lander on one of Titan's seas. Unfortunately it did not receive funding, but the lander could end up as the lander for the Titan Saturn System Mission if that ever gets off the ground.

Kraken Mare, Titan's largest sea, seen from a high altitude. NASA is researching the possibility of sending a submarine to explore the sea's depths. If it goes ahead it would be a remarkable mission, and one that has the potential to encounter what could be a complex ecosystem of methane-based life.

Flying in Titan's atmosphere is easy due to it's high density and the moon's low gravity. AVIATR proposes sending an aeroplane that would spend a year flying aound Titan, before attempting a landing. And there is ongoing research into a submarine that would explore Kraken Mare, the largest sea on Titan.

None of the above proposals are ever likely to launch. But there is a proposal that has a reasonable chance of getting full approval. Dragonfly, as it is known, would send a rotorcraft (similar to a quadcopter drone) to explore the moon. It would have the ability to fly at speeds up to 10 metres per second and reach altitudes of up to 4 kilometres. It would land and recharge from its radioisotopic generator during Titan's long nights. While landed it would sample the surface composition. It’s an ambitious and cost effective proposal.

The Dragonfly drone: an essential mission to Titan, and one that could be launched in the next decade

In July 2019 NASA will select either Dragonfly or CAESAR (a comet sample and return mission) for launch in the mid 2020s.

Titan's huge importance cannot be stressed enough, both to help ensure the future of our species by being one of the best places for a sustainable human colony, and by being the likely home of a completely new form of life.

Both of those reasons must ensure that Dragonfly is chosen.

They simply must.

Monday, 2 April 2018

Should All Interstellar Missions Be Silent?

The first detected interstellar object passed through the inner Solar-System last year, and is now heading away back to interstellar space. Named 'Oumuamua', the object, approximately 230 metres in length and around 30 metres wide, reached a speed of almost 88 kilometres per second at its closest approach to the sun.

Oumuamua: an interstellar object that passed through the inner Solar-System in 2017. It is potentially a camouflaged extraterrestrial embryo colonisation starship making use of our sun for a gravitational course correction.

There's a reasonable possibility that the object is artificial. It could be an interstellar colonisation mission that is using our sun to provide a gravitational  course correction, putting it on its final trajectory for its target star system, or setting itself up for another gravitational course correction in tens of thousand years time. And it could well have made some passive observations of our planet on the way through.

The object is too small to be a generation ship. A ship many times larger would be required to allow thousands of beings the chance to live and breed for many millennia as their voyage unfolds. But the ship is certainly large enough to be what is arguably a more efficient means of interstellar colonisation: an embryo ship. Such a ship would need to be much more advanced, requiring artificial wombs, and artificial 'parents' and educators. If Oumuamua is indeed such a vessel then it would be a remarkably complex technological marvel, and something worth pursuing when we have the means to do so.

On board an embryo star-ship a human colonisation crew is grown in artificial wombs

A lot of effort was made to detect signals from Oumuamua. None were detected. But why should any have been? Such an interstellar ship, with embryos only, would be fully automated, with no sentient crew (apart from perhaps an overseeing artificial intelligence). There would be little reason for the ship to make a transmission home, except during the safe interstellar phases of its voyage. Even if it did, it would be a very directed and focused transmission that would not hit our planet. And using stars such as our sun to provide course alterations would almost eliminate the need to use a means of propulsion, the emissions of which would be detectable, while transiting the system.

Maintaining a strict 'silent running' policy is essential for all pioneering interstellar missions. Only very targeted and rare encrypted transmissions to the home world should be made, and only when the ship is well away from possibly inhabited star systems. The rest of the time a starship should appear, apart from during the very closest of inspections, as a natural object. Any course corrections using a propulsion mechanism must only be made in interstellar space.

This seems to be the most sensible approach for us when we finally embark on colonisation missions to other star systems. And I would expect it's the approach taken by extraterrestrial civilisations that are already undertaking such voyages. That would certainly explain why we are not detecting any transmissions. Such strict controls are obviously being maintained during voyages, and when colonies are established. And such controls are no doubt being enforced on home worlds.

It's very likely that, at this point in time, our civilisation is one of the very few (even the only one) in our region of the galaxy allowing unregulated transmissions without considering how visible we are to civilisations in the surrounding star systems.

Listening for signals from extraterrestrial civilisations is a good idea. But is it wise to also transmit messages in the hope that one of them receives it? Perhaps we have not detected any civilisations because they have a good reason to keep quiet. Maybe we should, too...

This could possibly be to our advantage. It could act as a warning that our star system is home to a reckless species that does not care what it does, and who knows about it. It could make potential invaders think again and head for a quieter system.

Or more likely it could act as a sign that we are an undeveloped and ignorant species, unaware of the risks of attracting attention. We could be considered an easy target for eradication, and Earth as an easy project for redevelopment. Or we could simply be 'silenced' to prevent us bringing to this region the malevolence other civilisations fear.

We have only been transmitting radio signals for just over a century. That is not really enough time for any alien civilisation to analyse those signals and complete a voyage here. But there are already many star systems identified within a hundred light-years of our planet that could host life and even advanced civilisations. Our unfettered radio transmissions could have been detected decades ago.

If such a civilisation is advanced enough to already have starships constructed then it may not take much effort or time to prepare and direct one this way.

Extra-terrestrial visitors may well be friendly, but we should also be prepared for a hostile encounter

An interstellar ship or probe could be on its way to us right now. If it's able to reach speeds that are a significant percentage of the speed of light it could arrive by the turn of the century. We need to take seriously the possibility that an extraterrestrial civilisation has found us. 

They may be heading here right now.

It would be wise to prepare for an encounter with them within the lifetimes of those born today. We should hope that they are benevolent, and be ready to greet them as friends.

But we need to plan for the possibility that they are not.