March 25, 2017

Time Travel

A historical perspective

“What is time?” Asks James Gleick, in this history of Time Travel. “We know that it is imperceptible. It is immaterial. We cannot see it, hear it or touch it. Time is what clocks measure. But what is a clock? An instrument for the measurement of time. The snake swallows its tail again!” This is the kind of circular logic that the author tries to break out of in this engaging foray into one of the most mysterious concepts that has intrigued man since the nineteenth century.

Scholarly journal papers that announce new breakthroughs invariably begin with a review of past literature. Once in while, the literature review becomes bigger than any new concept that is being announced and in extreme cases, we end up with a what is known as review paper that merely surveys the subject without offering anything new. So is the case with this book. Rather than offering any new insight or even a clear exposition of any specific point of view, the author leads us through a grand tour of the various perspectives that scientists, philosophers and literary personas have explored in their respective efforts to put a structure around this most intriguing yet elusive idea of time. Given the breadth of subjects addressed, the depth is limited, but at least it creates a map of the terrain that the reader can explore on his own. This is the true value of the book under review.

Time as a matter of discussion entered the public domain with the HG Wells classic, The Time Machine, that set the tone for a whole genre. A science fiction story set in a different era -- complete with gadgets and behaviours that are dramatically different from what the author and his readers are accustomed to -- is one way travelling into the future, or the past. But the real flavour of time travel is revealed when the protagonists move forward and backward in time, into other eras or epochs. Such travel, creates contradictions, like a man meeting his own self in the past or the future or murdering his own father and negating his own existence, that form the backbone of many interesting novels that are discussed in this book.

Authors writing about time travel usually drift into philosophical discourses on the nature of time. Is it like a river? And if it is, is the observer standing on the bank or on a boat floating along with the river? Is it just the flexibility of the English language that allows us to save time, to spend time or even to waste time or do these verbs connect with certain real properties of time? These are questions that appear again and again but answers remain elusive to the original authors, the current author and certainly to the reader. In fact the author admits : “I doubt any phenomenon .. has inspired more perplexing, convoluted and ultimately futile philosophical analysis that time travel has.”

The book becomes more interesting when it eventually moves into science. The publication of The Time Machine by HG Wells was nearly simultaneous with some very serious scientific study of time as a physical dimension that eventually culminated in Einstein’s relativity. This, paradoxically, demolished the concept of simultaneity, that forms the basis of all mechanisms to measure time. All laws of physics, with the exception of the second law of thermodynamics, are indifferent to the direction of time and in principle, should allow people to move back and forth in time as they do as in left and right, or up and down. But of course, the ability to do so comes with the paradox of going back to the past and changing the course of history and hence it is ruled out, not by science but by logic. However Godel, the man who had upended the apple cart of mathematics with his Theorems of Incompleteness, has shown that such situations are not logically impossible and there could be physical worlds where there is no logical bar on time travel. This, along with the loss of simultaneity, leads to the concept of retrocausation where effect “precedes” cause and makes us wonder whether our language can support a discussion of such constructs.

Unfortunately, most of these deeper concepts are glossed over as the author regales us with descriptions of time travel that appear in various literary works. These I am sure are worth reading, not to understand the concept of time, but for the sheer pleasure of reading well written novels.

This review originally appeared in Swarajya,

February 18, 2017

Faster, Cheaper .. CRISPR

Let us imagine a quaint little colony where you and I live in peace but this peace is very often disturbed by outsiders who come in and dump garbage or play loud, ear-splitting music. What do we do? We collect photographs of the items that have created a nuisance in the past -- garbage bins, sound systems --  and store them in a photo album. We hire guards and give them  copies of photographs from this photo-album and ask them to check each and every visitor if he is carrying any of these unwanted items. When he finds a visitor who is carrying anything that matches with a picture in the album, he simply destroys the item or might even shoot the visitor. If a new culprit enters the premises, with a new disturbing item and is somehow overpowered by the community, then a picture of the new item is added to the album so that, in future, the guards can identify, destroy or deactivate it, if it is brought back again!
image from ScienceMag

This dramatised scenario is based on what happens when a streptococcus bacteria is attacked by a virus. Known hostile viruses, that are identified by a unique sequence of bases, or nucleotide molecules, in their DNA, are matched against a corresponding sequence in the bacteria’s DNA. Then a specific enzyme, the “gun”, is placed exactly on the matched part of the virus DNA and a “shot” is fired to break the virus DNA at the point of the match.  The virus repairs the DNA but the repair is never perfect. So the virus loses its original toxicity and the bacteria is saved from the viral infection. In the case of a new virus whose DNA signature is not available with the bacteria threatens the bacteria colony, some of the bacteria die, but those that survive keep a copy of the virus DNA signature in their own DNA, to be used against future attacks. To be technically correct, the virus DNA is not matched directly matched against its image stored in the bacterial DNA but against its complement, an RNA fragment, created from the DNA. This is like the neighbourhood guard being given a complementary negative of the image from the photo-album, not a photocopy.

This defence mechanism that bacteria have evolved over eons of evolution to defend themselves against hostile viruses is the backbone of a radical new technique called CRISPR/Cas9 that is sweeping swept through world of biotechnology and has revolutionised the way scientists modify the genes that define life and determine the characteristics of living organisms.

We have heard many horror stories about genetically modified (GMO) organisms but genes have been modified both naturally as well as artificially for many, many years. Random mutations or changes in genes happen naturally and they are propagated into progeny through the reproductive process while selective breeding of animals and plants are examples of artificial modification. But in all these cases, there is a lot of hit and trial involved and even when things work well, it needs multiple generations before the effect of the new genes become evident. Making similar changes directly, in a laboratory environment may be a little more easier, but not much. Current broad brush techniques are, slow, cumbersome, error prone and more often than not fail to achieve the desired goals. CRISPR/Cas9 promises to change this process so radically that it was widely tipped to win the Nobel Prize in 2016 but unfortunately it did not.

The genome, the sum total of all genetic material in any organism, is like a book  written with only 4 letters namely A, C, T, G. Actually each letter represents a base, an organic molecule. Specific sequences of letters form words. Some sequences of these words are irrelevant but other sequences of words form meaningful sentences that describe a specific recipe. In biological terms, a specific collection of meaningful sentences is called a gene and the recipe defines how the gene expresses or produces a specific protein. These protein molecules define how the living organism looks and behaves and their presence or absence can cause or prevent many diseases. The ultimate goal of genetic engineering is to alter these sequences of letters or bases in the genome of an organism so that beneficial outcomes, like disease resistance are enhanced and malicious outcomes like cancerous growth are inhibited.

But making these changes is not easy. The human genome can be viewed as a long chain of at least 3 billion letters -- spread over 23 chromosomes, or chapters, if we persist with the analogy of the genome being a recipe book. But only about 3 million of these are known to be a part of genes that play a definitive role, the rest are junk. To edit, or modify, an existing gene, any tool has to first locate its corresponding sequence of bases -- truly a needle in a haystack --  disrupt the sequence and then if possible replace it with another.

CRISPR -- Clustered Regularly Interspaced Short Palindromic Repeats -- are short identical sequences of bases that are located in the genome but are separated from each other by 32 unit sequences, called spacers, that are unique. These spacers, first located in bacteria that fight off invading viruses using the mechanism detected earlier, are images of various virus DNA that have attacked a bacteria in the past. Based on each such spacer DNA sequence, the cell itself, and now the scientist in a laboratory, can create an RNA fragment, called the gRNA, that will attach itself to a target DNA either in a virus, or in any other organism that the scientist wants to target -- precisely at the position where the sequence is identical to that in the original spacer. This is like walking down a street until you see a shop that is the shown in the photograph in your hand. Wherever, the gRNA stops, its sidekick, its  helper, a specific protein called Cas9 -- CRISPR associated protein 9 -- also stops, attaches itself, and like wire-cutter, makes a cut in the target DNA. This cut is repaired, but not perfectly, so the sequence of bases gets changed, the recipe becomes unreadable, the gene is disrupted and the corresponding protein cannot be produced. This two member team of gRNA molecule and Cas9 protein, that was earlier a defence mechanism for a naturally occurring bacteria is now a scientific tool that allows us to break a DNA at a very specific position in the chain.

Since the repair of the wire-cut DNA is imperfect, the gene is incapacitated or knocked-out. Very often this is desirable if the gene is responsible for some complicated disease. But what is even more interesting is if we can augment the two member gRNA, Cas9 team with a third member, an artificially prepared repair template that consists of a set of bases that we want to replace the original sequence with. Going back to our original analogy of the human guard, he is now given a bunch of flowers that he gives to the intruder after knocking out his garbage can and so instead of the stink of garbage, the intruder leaves our colony with the fragrance of roses.

CRISPR/Cas9 is a precision tool that can make small and precise changes in the DNA relatively easily. It is like using a thin brush to make changes in a precious painting instead of the earlier process of throwing a bucket of paint at it or using a high volume spray gun.

While CRISPR has been around since 1987, it was only in 2012 that Jennifer Doudna at the University of California, Berkeley and her collaborator Emmanuelle Charpentier  demonstrated the viability of using this two-molecule combination of gRNA and Cas9 protein to make precisions modifications on the genome. However in the same month, Feng Zhang of MIT’s Broad Institute filed for a patent for the same technology and the two teams have since been locked in an intellectual property battle of epic proportions. The commercial implications of this technology is immense. The race is now on to create specific gRNA molecules, that will locate and attach themselves to specific positions on the DNA of specific organisms, and the corresponding Cas proteins that will cut the DNA there. While human DNA is a very lucrative target as this may lead to cures of genetically transmitted diseases, even plant and other animal DNA is equally interesting as it would lead to disease resistant or high yield crops. All three principal actors in this drama have formed their own biotech firms to exploit the commercial benefits and Doudna and Zhang have already gone public. Finally, all three are widely tipped to win the Nobel Prize sooner or later for this remarkable technology.

Modifying the genetic code will lead to the creation of new, synthetic or hybrid organisms. This may or may not always be desirable but as we know,  there is no army that can stop an idea whose time has come and gene modification is one such unstoppable idea. Now we can do this faster, cheaper .. with CRISPR.

January 28, 2017

Asimov’s Children - Robots in Space

When I was a child, we used to spend Durga Puja at the foot of the Ayodhya Hills, Purulia where one of the fascinations was to spot artificial satellites, with our naked eyes, as they darted through the stars across the night sky. This Deepawali, parked in the pristine gardens of the Tumsong Tea Retreat near the dreamy town of Ghoom, Darjeeling, I was looking forward to a similar sky show when a thought struck me. Chinese fireworks may be out of favour this year, but right above me in the sky, was Tiangong 2, the Chinese permanent space station where two Chinese taikonauts had just arrived for their month long tour of duty.

Living in space is tough and the technology necessary to make space habitable and safe for humans is very difficult and expensive to develop. Hence China’s Taikonauts@Tiangong is an impressive feat, but is it really necessary? Should India try to catch up? Or is there an alternate, inexpensive approach? The sci-fi stories of Isaac Asimov’s famous “positronic” robots, that assist man in exploring space, suggest an elegant solution.

picture credit roberlan
Given the degradation and deterioration of the terrestrial environment, it is but inevitable that humanity will eventually escape into the vastness of space. But with our current knowledge of physics and state of rocket technology, nearby stars in the galaxy are simply too far to reach in a single human lifespan. So our search for habitable places is restricted to four principal candidates in our solar system. Mars is a close cousin of Earth in terms of terrain but has a very thin atmosphere. Titan has a dense atmosphere of nitrogen and methane and since it rains methane it has huge hydrocarbon lakes. Both Enceladus and Europa have huge oceans of good, life-friendly liquid water and the latter has a thin oxygen atmosphere as well. All these are potential places where human can plan on setting up colonies but unfortunately none of them will natively support life as we know it on Earth. The limitations of our terrestrial biology makes us unfit to survive in almost every space location. Our fragile human bodies have to be covered in either space suits or we have to create closed habitats that mimic our Earth in terms of temperature and atmosphere. How can we create such habitats that are big enough for a sustainable human population?

Given the astronomical amounts, pun intended, of energy required to lift material against our gravity and propelling them across space, it is clearly infeasible to have these habitats built on Earth and transported to their destinations. We have to look for ways to build them at the destination using materials that are sourced locally. Moreover, using human labour for construction leads us to a chicken-and-egg situation because for humans to live and work safely on biologically hostile locations, the location has to be first made habitable. This is where robots can step in. But these need not be anthropomorphic or humanoid robots that we come across in popular imagination -- the ones with blinking eyes that can walk or dance on two legs. Instead, they would be the kind of industrial robots that are already in widespread use in many automated factories today.

The first kind of robot that we would need would be like Google’s autonomous vehicles that can navigate across the terrain either on wheels or on tracks. Alternatively they could be drones that fly through whatever atmosphere that is available or autonomous  submersibles that could explore the methane lakes on Titan or the ocean depths that lie under the ice sheets of Europa and Enceladus. These robots would be the pioneers, the pathfinders that will explore the terrain and search for locations where we may find the right kind of materials necessary for building the habitats..

The second kind of robots are the ones that can drill into, excavate, or otherwise collect material and transport them to a central fabrication location. Basically these would be advanced versions of current mining and material handling technology that is already in use or is being tried in autonomous mining operations in many countries today.

The third category of robots would be the kind that are used in automated factories to build or assemble components -- components of living quarters, of energy sources, of chemical plants,  of material transportation systems and of the factories themselves and its robots. In fact robots must build other, simpler robots. All this manufacturing would in turn have to be done using either traditional material forming processes to create desired shapes or with 3D printers that are modified to work with the kind of materials that are excavated at the site. The 3D printed concrete castle built by Andrey Rudenko is a step in this direction.

In fact, the technology for building these robots is well understood. But in space, they need modifications. First they need to operate under different environmental conditions -- low gravity, bitter, sub-zero temperatures and a very different chemical environment. Secondly they need to ensure compatibility and interoperability between available material, the process of its extraction, transportation, processing and subsequent assembly into products. But what is most important is reliability. On Earth, equipment can be repaired or replaced but in space that is not possible because that will take years. Since faults are inevitable, these robots must be built with redundancies and self healing capabilities without increasing the weight. That is the real challenge.

These robots would also require an astonishing level of artificial intelligence to be able to operate almost autonomously. Asimov had playfully referred to the robots having “positronic” brains to distinguish them from simple electronic circuits that were then popular. Today, when hyper-exponential growth of deep learning and cognitive computing technologies is about to make digital intelligence more powerful that biological intelligence, it is important that these technologies be integrated into the next generation of extraterrestrial robots.

While the difficulty, and expense, of building, transporting and deploying these robots is high, they are several orders of magnitude lesser than what would be encountered if we send human beings. This is because a human being would need, in addition to all this capability, its own complex life support system along with redundant backups to address the inevitable accidents and failures. We can write off the expenses of a robot -- a piece of machinery -- if things go wrong, but the moral hazards of allowing a crew member to die in space because of a technical fault are far higher. So eliminating a human crew and replacing them with a crew of autonomous robots will lead to a dramatic reduction in costs and hence an equally dramatic increase in the economic feasibility of any such project.

One of the lingering tragedies of the Apollo program, that successfully landed men on the moon six times between 1969 and 1972, was that while it demonstrated man’s ability to arrive, it failed to initiate the process of building habitats. In the forty five years since man last walked and worked on the moon, even if a single habitable lunar colony was built, we would have had acquired by now, the confidence for building habitats on Mars or Titan. Unfortunately, the focus then, and perhaps even today, is to be able to simply go there and claim bragging rights. What we also need is to focus on what to do once we are there. Unlike tourists ticking-off important tourist destinations, we should plan to be immigrants who create homesteads and economic assets that will not only ease pressure on Earth but also serve as stepping stones to other destinations.

Today, NASA, ESA, ISRO and private entrepreneurs like Musk,  Bezos and Team Indus are racing each other to build the technology to travel into deep space. This technology is based on the efficient conversion of energy and smart control of very complex systems. There is no doubt that this is absolutely necessary if mankind has to liberate itself from an Earthbound existence and become a space faring species. But we also need another set of entrepreneurs who will focus on the complementary technology necessary to create a non-human construction crew that builds habitats. This technology will be based on robotics hardware that is controlled by artificial intelligence (AI) software --  the technology of autonomous robots. Team Indus is perhaps the only company in India that plans to go to the Moon by 2018 as part of the Google X-Prize competition and it would be nice if many more Indian companies were to create robots that ride on their craft and carry out mining and fabrication experiments on the Moon.

Fortunately, terrestrial business opportunities have created a big market for robotics and AI and today, instead of teaching machines how to perform tasks, we teach them to learn on their own how to perform these tasks. We need to adapt these technologies for use in space. That will be the grand realisation of Asimov’s fictional robots and a gigantic step for man’s journey towards the stars.

This is the third and last part of a 3-post series on Man in Space. The two previous posts are (1) Engineering India for the Space Age and (b) Habitats in Space - Our Second Home

This article originally appeared in Swarajya, the magazine that reads India Right

January 22, 2017

Donald Trump -- why am I not perturbed?

I just read in the newspapers that Donald Trump has been sworn in as 45th President of the United States and so the world is about to come to an end. It is the end of globalisation and the beginning of new protectionist order where the new mantra is buy American and hire American. It is the end of liberal democracy and the beginning of a new Putin-style illiberal autocracy. Francis Fukuyama and his thesis of "end of history" is now history -- "communist" USSR, in its new avatar of plutocratic Russia has eventually triumphed over the Anglo American vision of a new world order.

image footwearnews
But should all this matter to me? Obviously it does, as otherwise why am I commenting on Trump's inauguration? Trump is now the key person in the world's richest and most powerful nation and he certainly has the capacity to both help and hurt me -- or rather my interests. My interests are of course related to Calcutta, India and of late, and still rather tangentially, to the United States. So let me how Trump stacks up in my perception.

To begin with I really cannot quarrel with his philosophy of --  Buy American and Hire American. If I was in his place, or if I was the Prime Minister of India I would have said something identical. I need to look after the people near me, around me and most importantly those who have elected me and so I cannot criticize him if he does exactly the same.

One of the claims of globalisation was that it was a win-win for all parties but this far from true. By exporting good or services from region A to B, we make A richer and B poorer. Win-win is possible if there is a bilateral flow of goods and services. A one way flow of goods, as is the case from China to the US ( and also to India) cannot be a win-win however much we twist and turn our words. Its a win for China and a loss for the other. Similarly, one way loss of jobs from the US to India cannot be win-win. It is a win for India and loss of the US. A win-win is possible if there is a balance in the value that flows across the border in both directions.

As long as the US economy was big enough, when it was far, far bigger than, say, China, India, it could tolerate a loss -- or haemorrhage --  of jobs and wealth across its border but, as anyone who has solved the "water flowing out of tank" series of  problems in Jadav Chandra Chakraverty's classic book on arithmetic would know, there will come a time when the tank will run dry and not all the wishy washy theory on the win-win of globalisation will work. Let us admit it, the globalisation that we have had so far was never really a win-win game, its a zero-sum game. Someone wins and someone loses. As long as Americans were rich enough, they could talk big about globalisation and all that, while we, the poor in India would never allow imports of good and services because we had to save our precious "foreign exchange". But now that the US has been bled dry  -- well you can always debate on how dry or poor the US -- it is impossible for them to be as generous as they once were. Let us face, when push comes to shove, everybody looks after his or her own interest.  So is the case with Donald Trump. [ update ] Wonder how many of us in India would cheer if people from Bangladesh were allowed to come in and start working in our shops and establishments at lower wages?

Now let me see the Trump phenomenon from my narrow, selfish perspective of being an Indian, living in India and being a beneficiary of a buoyant Indian economy. What does the US buy from India? I looked at 2012 data and found that the US accounts for only 25% India's export of US$ 142 billion which again would be around 10% of India's  2012 GDP of US$ 1800 trillion. So if the US stops buying anything from India -- and this is  highly unlikely -- the impact is about 2.5% of India's GDP. Now let us see from the other side and estimate the possibility of the US stopping all imports from India? My data shows that India accounts for only 2% of all US imports! China accounts for 22% of all US imports, while Mexico and Canada accounts for 13% each and so any hostile action towards exporting countries would first be directed towards these three. India's 2% is quite safe and so is our 2.5% of the GDP that finds its way to the US!

So if Trump starts to restrict imports, the one to get hurt the most is China, who of course is no friend of India and so what hurts a non-friend, is of little concern to me.

Now let me turn to "Hire American" part of his agenda and as we all know that this can only impact our H1B "IT professionals" who are in the US. India's IT industry -- of which I have been a participant -- is worth US$ 147billion in 2015, out of a GDP of  about US$ 2000 billion. Of this US$ 100 billion is exports mainly to the US. This is about 5% of the GDP. A lot of this, US$100 billion is in the form of offshore delivery that does not need H1B visas and is delivered digitally out of India. The total number of H1B visa holders in the US is about 800,000 in 2013 and about 65,000 visas are issued every year. Assuming that 65% H1B visa holders are from India this would be only 18% of the 3 million people who are directly employed by the IT industry in India. So assuming that all Indians with H1B visas are booted out of the US, the loss is capped to 18% of the IT industry which in turn is about 5% ( US$ 100B / US$ 2000B) of India's GDP. That is an impact of about 1% assuming -- rather ominously -- that all H1B visa holders from India lose their  jobs and all Indian IT professionals are working on US project. In reality, the impact will be far less, because with at worst, new visas will may not be issued or renewed.

In fact, the threat to the IT industry is not so much from Trump's H1B policies but from automation of services and the reduction in the number of people required to deliver IT services. Most of our IT professionals are rather low end "techies" often referred to as cyber-coolies who have joined the profession, not because of any love or aptitude for the trade but because of the easy money to be made there. As automation eliminates many other blue-collared jobs, so too will these jobs gets eliminated and Trump has no role in that. In fact, if the IT industry in India has to survive, it has to wean itself from the labour arbitrage model of delivering inexpensive services and move into the high end of high value products -- but that is another story that has already been explored, ad nauseum, by many others.

Now that fear of the "Buy from America and Hire from America" is behind us, let us look at the other "grotesque" aspects of the Trump presidency!

We are told that he has no respect for women and is hostile to the LGBT community. Condemnable as that may be, our politicians in India are no better and if we can live with them right here in India, I am sure we can live with Trump and his misogynism in distant America. It is up to the American citizen and the American electorate to deal with him as they think fit. Just as I do not want Americans to interfere with our caste, religious and social issues, I have no interest in getting entangled with their affairs. We have enough problems here of our own making right here. In fact I only hope that unlike Barack Hussein Obama he does not instigate a hypocritical firestorm around the fake issue of "intolerance" in India -- on the instructions of the India's secular enemies.

Which brings us to his attitude towards minorities or to put it rather bluntly towards political Islam.

Hillary Clinton was in the pay of her Saudi Arabian paymasters, which is why she and Obama encouraged the rise of ISIS to counter the Iranian influence in the Middle East in general and Iraq and Syria in particular. The Great Game in the Middle East today is that the new Russia, under Putin, is trying to muscle into traditional Anglo-American turf, from Ukraine to Syria and in this they are opposed by the Saudi led Sunnis and hence assisted by the Iran led Shia. In this Great Game, Clinton was firmly in the Saudi - Sunni camp, hence opposed to the Iran - Shias, and so Russia's Putin threw in his weight behind Donald Trump so that he would win and support, or at least not oppose, Putin's grandiose plans in the Middle East.

How does that impact India?

India is in the crosshairs of political Islam with Ghazwa-i-Hind being a long sought political goal of both the Sunni and the Shia factions, neither of whom have any love lost for the Indic way of life and its inclusive philosophy. However, in the near term, Wahabbi Sunni Islam, funded by Saudi Arabia and provisioned by Pakistan is the more potent and dangerous threat both for India and the world. Hence, the Saudi-funded, Saudi-affiliated Hillary Clinton would have been an utter disaster.

But is Trump a friend of India and of Indic civilisation? Unlikely. His first interest is in himself and then his in cronies. Fortunately he and and his cronies are now allied against political Sunni Islam -- and as long as he remains so, their interests would be aligned to mine and ours.

Finally, Trump is supposed to be illiberal or anti-liberal. Unfortunately, the whole concept of being "liberal", of being "tolerant" of others and of "agreeing to differ" has disappeared. Violent intolerance is the new normal. For example, political Islam does not seek dialogue, only dominance. So if you are tolerant and liberal you are considered weak and liable to be hurt if not actually exterminated. In effect, you can be tolerant only if  you tolerate intolerance and if  you do so you would be eliminated along with your tolerant beliefs. So  you can be liberal and tolerant if and only if you have a death wish! As I have explained in my blog post, and in Swarajya, the Second Law of Thermodynamics tells us that we will inexorably move towards more and more chaos, not just in the world of physics but also in society.

In all this rise of violent intolerance, Trump is neither here, nor there. He is just another milestone in the long march to chaos. So what is there to be unduly alarmed by his ascendancy?

December 25, 2016

Habitats in Space : Our Second Home

If not on Earth, where else can humans beings be? Not as a traveller in a spacecraft or as a one-off tourist on the Moon but as an immigrant, or a colonizer who sets up a permanent residency for multiple generations. Given our current knowledge of physics and the state of propulsion technology, we really do not have the ability to travel to other stars in a reasonable amount of time, so our search for that second home for humanity is restricted to our own solar system. Where do we start?

photo credit Tittat427

There are two divergent points of view on where to locate such an extraterrestrial colony. Some believe that the colony should be located on a natural body like a planet, satellite or an asteroid while others think that the best bet would be an artificial structure in orbit around a planet or in space. There are pros and cons for both. What is common to both approaches is the realisation that any environment outside the terrestrial biosphere that we currently inhabit is inhospitable if not actually hostile to all kinds of known lifeforms, including humans. The availability of a magnetosphere that shields us from cosmic radiation, of liquid water that is fundamental to our biology and of an atmosphere that supplies us with oxygen for metabolism is essential but unfortunately there is no place where all of this is readily available. So wherever we go, we would need to create this environment artificially. Question is, where is it that this can be done with the least effort or at lowest cost.

The obvious place to think of is our Moon because it is closest and we have already been there. But because it is so deficient both in water -- with just traces of this precious liquid found by India’s Chandrayaan -- as well as in gaseous oxygen and nitrogen, that it is not thought to be worth exploring. The only real value of the Moon is as a source of minerals that can be mined and more importantly lifted off the surface relatively inexpensively because of the low gravity compared to Earth.

Mars on the the other hand is a more Earth-like location. The physical terrain is very similar to our rocky arid deserts and while no liquid water is present today, there are huge ice caps in the polar region that if melted can provide all the water that we would ever need. What is nice is that because the axis of rotation of Mars is tilted just like that of Earth, there are regular seasons and while winter temperature at the poles can be as low -150O C, summer temperatures near the equator reach a comfortable 35O C. The atmosphere is thin and the air pressure on the surface is about 0.6% of what we have on Earth. But since most of this is carbon dioxide, there is a good possibility of using terrestrial plants to use sunlight and gradually convert carbon dioxide into precious oxygen that both plants and animals can use. Melting the polar ice caps to release water and gradually converting carbon dioxide into oxygen could be the first steps towards terraforming Mars and creating an Earth like environment. After water and oxygen, the third challenge is the lack of a global magnetic field that would shield residents from cosmic rays but the existence of umbrella shaped auroras in some areas show the promise of local magnetic shields that could prove useful. But in areas bereft of such protection, thick walls or living underground would solve the problem.

While Mars may look like a good place to pitch our extraterrestrial camp, there are three other possible locations.

Titan, the largest satellite of Saturn, is a world where liquid hydrocarbons play the role that water plays on Earth. Titan has a dense atmosphere consisting largely of nitrogen and it rains hydrocarbons, like liquid methane, every now and then. This leads to the  formation of liquid methane lakes near the poles. The climate, along with the winds and the rain, creates surface features very similar to Earth with dunes, lakes, rivers, deltas and oceans that are dominated by seasonal weather patterns. Titan is cold, very cold and far away from the sun and so solar energy may not be a feasible solution. But it has water ice and if the energy potential of the vast quantity of methane -- and that is a big IF  -- can be unlocked with the help of oxygen extracted from water then we have one of  largest sources of hydrocarbon energy in the solar system. Again, even if we do not go to live here, Titan could be be source of energy, like the Middle East on Earth, that could be extracted and transported to other worlds inexpensively, because of Titan’s low gravity.

Next stop is Enceladus, a small rocky world covered with water ice that orbits Saturn. But what is interesting in Enceladus is that even though surface temperatures are far below freezing, there exists beneath the thick ice shell, vast oceans of liquid water that are kept warm by the tidal effects of Saturn’s immense gravity. In fact, so hot is the interior that plumes of salty water are regularly seen to erupt out of the surface in a manner similar to geothermal geysers on Earth. These salt-water plumes also contain nitrogen, as ammonia, and organic molecules like methane, propane, acetylene and formaldehyde that prove the existence of  hydrothermal activity and potential energy resources. In fact, the presence of these products also signal the possible existence of life forms similar to those found on Earth.

Our third and final stop on this current tour of possible locations for our second home is Europa, another ice and rocky satellite that orbits Jupiter. Europa too has a vast, subterranean ocean of liquid water warmed by the immense tidal effects of Jupiter’s gravity and it ejects plumes of water spray similar to the kind found on Enceladus. There are two other features that make Europa possibly one of the most habitable locations both for terrestrial as well as non-terrestrial life forms. First it has a magnetic field caused either by a nickel-iron core or a subterranean pool of salty, liquid water that forms a subsurface conductive layer. Second, it has an atmosphere, which though thin and tenuous consists primarily of oxygen!  This is of immense value for any human colony that may be located there. Because of all these factors, Europa has emerged as one of the most likely locations in our Solar System for potential habitability.

Mars, Titan, Enceladus and Europa all seem to have the basic ingredients necessary to support human life but given the lack of an Earth-like environment, man will have to create an independent structural unit with controlled, ecological life support systems that are isolated from the local environment. If this be the case, why build this structure on a planet or a satellite? Why not build the structure in space itself?  This is the logic behind the design of space habitats that could either be in orbit around planets or around Lagrangian points -- gravity wells where the gravitational attraction of two large astronomical bodies tend to, kind of, cancel each other out. These could be huge structures, many kilometers long and shaped like a cylinder or a torus that spin on an axis to generate the sensation of gravity. Powered by an abundance of solar energy and sustained by recycling materials on a mini-planetary scale, these structures could be sustained by advanced agricultural techniques based on greenhouse and hydroponic technology. Many of these technologies already exist but the biggest challenge would be to source the construction materials. Carrying them from Earth would be impossibly expensive but a more feasible approach would be to mine them from other, low gravity locations. That is where robots will come in very handy because they can be made to mine and transport materials from inhospitable worlds.

Now that we have some options for our second home, some of us will ask the question -- why on Earth, pun intended, would we want to go there? One reason of course could be the deterioration of the political and ecological environment, that may make Earth uninhabitable. There is also the finite, non-zero probability of some incredible accident that may wipe out life on Earth. But perhaps the most biggest compulsion would be man’s curiosity. 200,000 years ago, primitive man walked out of Africa and spread out all over the world. Later on, people from south India crossed the Bay of Bengal to colonise south east Asia and Europeans spilled out into America and then Australia. Each such excursion led to vast increase in exploitable resources. However in each case, in each society, there would have been sceptics who would have wondered why?  But then there must have been others who said “Why not?” and it is the latter who would eventually prevail!

So would be the case for man in space. Why Not?

this article originally appeared in Swarajya, the magazine that reads India right

December 09, 2016

Chidananda Rupaha Shivoham

One of the finest expositions of the Indic School of Thought.

Shivoham (शिवोऽहं ) by Adishankara - performed by John Scottus Students from Rutger Kortenhorst on Vimeo.

November 28, 2016

Engineering India for the Space Age

Elon Musk may have suddenly become the glamourous mascot of a new, post Apollo, space age but the fact remains that the destiny of mankind is among the stars. While many people will keep on trying to salvage what remains of spaceship Earth from the environmental, social and political scourges that threaten it, it is but inevitable that a significant, space faring community will emerge that will seek to live and work outside the planet -- like European emigrants going to America. Are we in India ready for this? Will we just watch and cheer while others depart? -- as it was in 1969 when man went to the Moon? Or should we as nation participate in these great voyages?

credit : gwydion1982
Astronomers tell us that there must be, thousands of habitable, earthlike planets in orbit around various stars in our galaxy. Unfortunately, the distance between stars is so great that we have no means yet, not even theoretical ideas, on how to build spacecraft that will be fast enough to travel to another solar system in the lifetime of a human being. But travel within our own solar system is  possible with technology available today. So to be realistic, let us focus on our own solar neighbourhood.

In a recent paper in Universe Today, Nancy Atkinson has identified Mars, Europa and Titan, two satellites of Saturn and Enceladus, a satellite of Jupiter as possible destinations based on the availability of a solid surface, the presence of an atmosphere to protect against cosmic rays, the existence of water and hydrocarbons and a temperature range that supports liquids. There may or may not be pre-existing life in these worlds but the environment can certainly support the carbon based life forms that we are familiar with. More importantly, we already have the rockets and spaceships that can take us to these destinations in a reasonable amount of time. But going there is only a one part of the story -- a story that is being written with great enthusiasm by NASA, ISRO, SpaceX, Blue Origin and other companies. What do we do when we get there?

In the early years of the 15th century, the Chinese government sent out flotillas -- the Zheng He fleets -- to impress people around the world with the size and power of their ships and the glory of the Chinese empire. At the same time, Portuguese and Spanish sailors, with far smaller ships, also set sail but their aim was to create outposts from where they could carry out trade and commerce. The Chinese ships achieved little even though they were far superior to the European ships but as we know from history, it was the latter that ended up ruling the world -- both politically as well as economically. Space voyages tomorrow would do well to keep in mind that it is not enough to just go there. We need to create habitable colonies where humans can stay and plan for the next part of their journey.

Unfortunately, none of the feasible destinations that we have identified can natively support human life as we know it. The first thing that we need to have is a Hab, a habitat, that we human beings can live in. This Hab must be as large as a big house or a perhaps a small township that has its own oxygen rich atmosphere hermetically sealed against the alien atmosphere of the outside world. But a Hab as big as we need cannot be built on Earth and transported to the colony, it needs to be built there. So before we have a Hab as big as we want, we need a Fab -- a fabrication facility -- at the location, that will be used to build components of the Hab.

The Fab, would in turn have three pre-requisites. First it would need a source of energy and while nuclear power carried from Earth would be the initial source, it would eventually need to have gigantic solar cells to harvest sunlight, however weak it may be, and provide sustainable energy. The huge hydrocarbon deposits on Titan could also be used if we can get a source of oxygen to burn them. The second second requirement of  the Fab would be raw materials to build the Hab and also the solar cells to power both the Fab and the Hab. Again, this raw material cannot be transported from Earth but would have to be mined near the Fab / Hab complex itself. The third facility in the Fab would be autonomous manufacturing facilities -- or what we refer to as smart robots..

Human beings with their fragile lives and the need to protect them from accidental death means that it would be far simpler and inexpensive to use robots as much as possible for all mining and manufacturing activities. This is one area where Indian companies may wish to focus on if they want to remain relevant as mankind ventures out into the vastness of space. Space or not, robotic manufacturing has already become a key feature of the terrestrial economy and unless Indian companies adopt to this technology in a big, big way the Make-In-India concept would be rendered irrelevant. However the focus should not just be on using robots but on building robots as well -- robots must become the centrepiece of India’s capital goods industry. This will create a stable platform on which space faring robots can be built.

Robots have sensors to detect cues from the environment, actuators to move and control materials and other machines and all this is held in place by artificial intelligence (AI) software. This same AI, that is the basis of the autonomous, self driving cars pioneered by Google and developed by Tesla should now be extended to autonomous equipment for mining and material handling that would be essential to feed the Fab at the space colony. This presents another window of opportunity for Indian engineering companies to place a toe-hold in the line-up for the space race. Manufacturers of earthmoving equipment must start exploring ways and means to adapt their products for autonomous operations in different worlds. The first step would be of course to build autonomous products for terrestrial operations and once we have a level of confidence in the technology, we can seek to adapt them for space. For example, seabed mining with autonomous submarines could become a model for mining operations on Enceladus that has huge water oceans under a layer of clean white ice.

Autonomous mining is not science fiction. The Mine of the Future initiative of Rio Tinto and the Next Generation Mining program of BHP have both started working on autonomous mining equipment and multiple Chinese companies are also in the fray. In India too, we must start working on these technologies, not just in preparation for their eventual deployment in space but for benefits that will accrue in the terrestrial economy, today.

Once the minerals have been mined, we would need to convert them into building materials that will allow us to create a series of increasingly bigger and more sophisticated Habs. Materials that are easy to work with and yet good enough to protect human lives from the harshness of the extra terrestrial environment would need to be designed along with the capability for autonomous manufacture and fabrication. This calls for new thinking in materials science and in construction technology that can be automated easily with smart robots.

The final component of any space colony is the farm to grow food. In the movie Martian, which demonstrated some very feasible technologies necessary for a human to survive on Mars, we saw the protagonist growing potatoes in a fairly hostile environment. In a recent experiment at the Wageningen University and Research Centre, “scientists have managed to harvest 10 crops, including tomatoes, peas, and rye, from soil that mimics the conditions on Mars”. Farmbot, a precision farming DIY robot built with off-the-shelf components like Arduino and Raspberry Pi and based on traditional CNC machine tool guidance technology, could be a good model for autonomous farming under tightly controlled environments.

Rockets and spaceships are necessary but not sufficient in our quest for new homesteads beyond Earth. A broad consortium of engineering companies is necessary to provide R:U:M  रोटी, ऊर्जा और मकान -- food, energy and habitat -- on extraterrestrial locations and to build the capital equipment capable of autonomous mining, mineral processing, fabrication and assembly. A community that plans to go to space will need to dream, design and demonstrate these technology capabilities here on Earth. Since these technologies have a direct impact on the current terrestrial economy there is a strong business case for investing in such dual-use products right now. Expertise acquired in these areas is not only good for business today but will also provide the platform for that big leap into space.

A national convention on “Engineering India for the Space Age” would be a good launch pad for  the national goal to become a space faring nation in the next 50 years.

This article was originally published in Swarajya.

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