It Really Is Rocket Science

By Adam D.A. Manning

Space has long been a wonderful source of inspiration for many people. Numerous scientists and engineers have pursued careers from having the touchpaper of their imagination lit by the thrill of exploring Space, whether that be in the context of science fiction such as Buck Rogers or Star Trek or the real deal, such as the Apollo moon missions.

Even those, such as myself, who do not have a Space career can still get involved and learn more. Recently the British Interplanetary Society (BIS) held a special day of talks billed as an “Introduction to Rocket Science” which was an opportunity for the curious to hear from leading experts. The BIS is the world’s oldest space advocacy organisation and has for over eighty years looked ahead in visionary thinking about the exploration of Space.

To my delight, none other than the prestigious Royal Institution (RI) in London was the venue for this blast off into astronautics. The RI is a cherished organisation in the UK and many of us are familiar with the science-themed Christmas Lectures that are held there. The talks were held in the same lecture hall used for the Christmas Lectures, which gave proceedings a special, historical atmosphere.

As always, the BIS warmly welcomed members of the audience and prior to the launch of the event, I noted how many young children were in attendance. As a father, it is clear to me how quickly children grow up and so reaching out to them with events of this type is so important in firing their imaginations and giving them a valuable look into these areas.

The day featured a variety of presenters on all sorts of Space related topics and included some practical experiments, which reminded me vividly of the famous Christmas lectures. This included a beautiful, ultra-light model aircraft powered by a rubber band to demonstrate the principles of flight, followed later by a dramatic combustion of an alcohol-based liquid in a canister to loudly demonstrate something of the power of a real rocket engine.

Several of the speakers touched on how their careers had progressed and this included Abbie Hutty, a Senior Spacecraft Structures Engineer who is working on the ExoMars rover vehicle. In doing so, she built on the theme of reaching out to the youngsters in the audience and planting the idea in their minds that they too might one day get involved for real. She spoke compellingly about the fascination of her work and the sense of achievement.

One of the most powerful presenters at the day was Professor Chris Welch, a Fellow of the BIS. He described how hearing a talk by Carl Sagan at the RI in 1977 on the importance and urgency of the human exploration of Space had motivated him in turning his interest into his vocation. Later Professor Welch debated on a key issue for Space exploration: Are astronauts really needed or should all exploration be left to robotic missions? The view of the audience was unsurprisingly that human exploration of Space should continue.

Another star speaker was Cady Coleman, a NASA astronaut and a veteran of two Space Shuttle missions and a stay on the International Space Station. It was a special thrill to me, along with many others in the audience, to hear for the first time from someone who had been in space. Cady Coleman soon earned the gratitude of her RI audience with kind remarks about British space hero Tim Peake, referring to him as an exemplary astronaut and a gifted science communicator.

The extraordinary growth in the discovery of extrasolar planets (that is planets outside of our Solar System) was the subject of another talk. Dr Don Polacco detailed the progress in finding these, including extrasolar Earth-like planets, and noted the tendency for somewhat over-enthusiastic, if not to say inaccurate, headlines that can arise from new findings. I was particularly fascinated by his view that if we should one day be able to communicate with an extrasolar civilisation, the chances are that they would be millions or even billions of years more advanced than us.

It was an enlightening and entertaining day with a rich diversity of speakers. Hearing directly from leading academics and practitioners helps take an interest off the page and here, this feeling was bolstered by being at the RI, with its prominent role in advancing scientific knowledge. Attending events of this sort are not only a great way to learn more – they can inspire a feeling of being involved, of being an active participant ready to take further steps in an adventure into science. 

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What Does the Pledge of Allegiance Teach?

Photographer: Mark Wilson/Getty Image

By Leyden Marks

In many schools across the United States, school children routinely stand to recite the contemporary Pledge of Allegiance in their classrooms, usually in the morning.

Some of the common arguments against this repetitive school-day exercise are familiar to me. (Some background on various text versions and the dissimilar complaints follows below). However. I haven’t heard before, from anyone else, one thing that really bugs me regarding the practice.

I just don’t like what the ritual itself teaches to classrooms of youngsters across that nation

Here’s my protest:  It seems to me that this incessant “pledging of loyalty to the nation” is teaching students that it’s acceptable, even expected, that you don’t really need to mean what you say!

In school, with the Pledge, superficiality and hollowness in one’s declarations is ratified.

In school, just uttering the words of assurance repeatedly is actually passable behavior. You needn’t have to mean them. In fact, it seems that you aren’t even expected to mean them.

In school, you must repeat the Pledge of Allegiance (over and over, again and again) because you apparently didn’t take to heart what you just said yesterday (or last week) when we previously said the Pledge. Or maybe conditions somehow changed overnight?

It appears that the school suspects that you didn’t seriously mean what you said before. Why else would it be asking you to keep up the loyalty pronouncements?

If you took the pledge seriously in the first place, you’d say it, and that’d be that. You’d have genuinely pledged.

Some People’s Take on the Pledge

Students today can escape this persistent ritual, if they seriously wish to do so. Not every student has to participate because, in 1943, the U.S. Supreme Court ruled in favor of plaintiffs who sought exemption from the exercise on religious grounds. (Subsequently, schools could no longer require students to recite the Pledge if it was contrary to their religious beliefs.) Taking pledges was serious business for those Jehovah’s Witnesses folks.

In a later case against the practice, an atheist (a quite serious one) complained about the phrase “under God” in the Pledge. Michael Newdow was also taking the Pledge content quite seriously.

Those two words had been inserted into the text of the Pledge in 1954 by an act of Congress. Filed initially in 2000, the claimant contended that those added words endorsed religion and thus violated the Establishment Clause of the U.S. Constitution. (Rationale: The practice of teachers, as agents of the government, leading students in a pledge acknowledging God promotes the belief the nation is under God, and that would be an article of monotheistic belief).

Wikipedia offers a summary of that case, which stirred much public controversy at the time and culminated in the Court simply avoiding the actual constitutional question that the claimant had raised. So the Pledge ritual has maintained its 1954 wording to date.

Looking Back Briefly at the Pledge Ritual

Even before 1954, the Pledge wording had changed from the original text, which was created for a one-time flag-raising ceremony in Columbus Day celebration, but was quickly transformed into a ritual.

The first (Oct. 12, 1892) stated:

“I pledge allegiance to my Flag and to the Republic for which it stands, one nation, indivisible, with liberty and justice for all.”

Notice the words “my Flag” in the first pledge. This phrase was in the Pledge until 1924, when a National Flag Conference announced that the words “my Flag” would be changed to “the Flag of the United States of America.” (This change stemmed from a fear that that the children of immigrants might confuse “my Flag” for the flag of their homeland)

Thus the second pledge was:

“I pledge allegiance to the Flag of the United States of America, and to the Republic for which it stands, one nation, indivisible, with liberty and justice for all.”

The “under God” phrase was added during the Eisenhower administration at the urging of the Knights of Columbus in order to distinguish the United States from the “godless atheistic’ communistic Soviets. President Dwight D. Eisenhower, fearing an atomic war between the U.S. and the Soviet Union, joined the lobbyist requesting changes be made

The original Pledge was recited while giving a stiff, uplifted right hand salute. This manner was criticized and discontinued during WWII, due to its being so alike the gesture used by citizens of Nazi Germany to salute Hitler. The mode of saying the pledge shifted to one of uttering the words with right hand held over the heart, which was established practice by 1954 when the final change in wording took place.

To Pledge [Anything] – Doesn’t it Mean Something?

According to the dictionary, a pledge is a “solemn promise.’ You make a promise, a serious promise. Some dictionaries follow that with “…to do something” or “…to refrain from doing something.”

Google it, and see if you don’t agree that the term’s various meanings should convey something serious. To pledge is to make a sincere, earnest, intense vow.

If that’s the case, then why has the Pledge of Allegiance become so not like a vow?

As a promise, it’s shallow and hollow, not heartfelt and sincere. It isn’t really an honest, grave, pledge of loyalty, anyway.

In a marriage ceremony, one takes a vow. It’s serious. Although the feeling may dwindle and even disappear over time and circumstance and end with divorce, the one-time vow works at the time. It certainly isn’t repeated next day at breakfast Ornext week

Nor does it have to be repeated, ever again. One has pledged. It was a deep promise, sober, intense (certainly not frivolous). Even if, after many years, a couple decides to “renew the vows, the occasion is taken as one with some solemnity. A pledging to one another is intense.

But what about the Pledge of Allegiance? This pledging of loyalty to the nation. The words being uttered are mechanically issued. Much like the scout pledge, too oft-repeated, the substance rings rather hollow. “Saying the Pledge’ in the classroom, words routinely uttered, becomes more like hanging up one’s coat before being seated than issuing a genuine promise. One needn’t really take it to heart.

Are these who so loudly protest any change whatsoever in the current Pledge (like going back to the pre-“under God” secular version to which everyone might accede), the same automatons who

memorized the words before they could think what making a real sincere loyalty vow would entail?

They’ve been taught. Quite enough back then (and now) to simply utter the words over and over again. One takes the words seriously, perhaps, but not the Pledge.

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Space Law and Extraterrestrial Resources – Who Owns the Moon?

By Adam D.A. Manning

The legal aspects of the ownership and use of lunar and other extraterrestrial resource, such as asteroids, and their implications for endeavours of this sort are important in considering how space development may proceed. The law will have an influence on such efforts, particularly if they are private and commercial, as the nature of ownership will directly influence how they can be used and sold.

The dawning of the Space Age in 1957 with the flight of Sputnik 1 and the International Geophysical Year of 1957/58 focussed thoughts on the need for a legal regime to manage and regulate space activities. The United Nations was quickly recognised as the most appropriate forum for drawing up the principles involved. An important influence on this developing body of legal principles was the Antarctic Treaty System, which viewed Antarctica as a pristine wilderness that needed to be preserved. Outer space was seen in a similar way.

After a series of UN resolutions setting out initial principles in the early sixties, the Outer Space Treaty (1) was enacted in 1967 and is the most important legislation in this area. Article 1 refers to outer space as the “common province” of all mankind. This concept is continued in Article 2, which states that outer space, including the Moon and all other celestial bodies (apart from the Earth of course!) cannot be owned or appropriated by any nation state. The prohibition set out in Article 2 includes ownership by way of occupation; for example simply occupying a site on the Moon, as in a base or station, does not of itself confer rights of ownership.

The Treaty envisages bases being built on the Moon or Mars, for instance, but says that other nations will have the right, subject to reasonable notice, to inspect them. So, if a company builds a mine on the Moon with some secret commercial processes, it has to allow other people in to inspect. These obligations apply to companies or individuals of state parties to the Treaty, as the Treaty makes nation states responsible for the actions of their citizens and legal persons (such as companies) while they are in space.

The Outer Space Treaty was ratified by a large number of countries and is considered an important source of legal principles that apply to space, principles that are likely to be long lasting and very influential.

To some countries, the Outer Space Treaty did not go far enough. The developing nations were concerned that if the space faring nations (which were of course powerful, developed nations) utilised the resources to be found in space, they would be left even further behind. After much negotiation, in 1979 a further UN treaty known as the Moon Agreement (2) was enacted that sought to advance these issues.

As well as repeating the prohibition on ownership of territory in outer space, the Moon Agreement goes further by prohibiting the ownership of any of the substance of a celestial body, such as the Moon’s regolith or the minerals to be found in asteroids. Instead, it proposes an international regime that would administer and regulate the exploitation of the resources of outer space. These resources are, according to the Moon Agreement, the “common heritage of mankind”, a concept that requires the exploitation of outer space resources to be for the benefit of all humanity and in particular developing countries which are not in a position at present to directly explore the Moon or other parts of space.

Other Articles in the Moon Agreement require that those exploring space must take measures to avoid the disruption of the “existing balance” of the environment of the Moon, or other parts of outer space.

This is a profoundly different approach than the simply exploitative and as a result the Moon Agreement was not ratified by any of the space faring nations. The USA felt that it was too “socialist” and the Soviet Union disliked the concept of the common heritage, fearing it too similar to a concept of “inheritance” and the wealth this implied. As a result, the international regime it sought to instigate was never taken any further. This unfinished legal regime complicates the position for companies interested in the exploration and even exploitation of space, as they have no clearly enforceable rights of ownership to whatever they find or use.

These Treaties were drawn up in a time when access to space was the preserve of nation states. Now private enterprise seeks to push back the final frontier. In the USA, this has prompted fresh legislation, including the SPACE Act (3). Headlines have been written suggesting the SPACE Act entitles individuals and companies to claim territorial rights to asteroids or parts of the Moon. This is misleading. The Act supports, within the context of the USA’s domestic law, claims by US citizens and companies to rights to extraterrestrial resources, but makes it clear that this is subject to the USA’s international obligations, for example under the Outer Space Treaty.

Earth bound precedents can help us consider how Space Law might move forward. The Antarctic Treaty System, a forerunner for Space Law in this area, has been successful in halting commercial development in its jurisdiction. Yet do these same concerns of preservation apply quite so clearly on the Moon or to asteroids? A closer analogy is the law of the deep seabed, where the common heritage of mankind principle is relevant as well. The deep seabed could be a source of mineral resources, in a way that is reminiscent of hopes for minerals from asteroids or the Moon. The International Seabed Authority administers this legal regime and its history could provide insights into how Space Law in this area might develop.

If either countries or companies are seeking to use and exploit the resources of space, these legal issues will have to be looked at again to ensure they have the rights to do so and indeed recently the American government has shown an interest in doing so. Unless we are content to see a tragedy of the commons (4) in space or a lawless free for all, the rule of law is going to be important in ensuring the enormous investment required is safeguarded.

  1. The full name for the Outer Space Treaty is the Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, Including the Moon and Other Celestial Bodies. See http://www.unoosa.org/oosa/en/ourwork/spacelaw/treaties/introouterspacetreaty.html

  2. The full name for the Moon Agreement is the Agreement Governing the Activities of States on the Moon and Other Celestial Bodies. See http://www.unoosa.org/oosa/en/ourwork/spacelaw/treaties/intromoon-agreement.html

  3. The full name for the SPACE Act is the Spurring Private Aerospace Competitiveness and Entrepreneurship (SPACE) Act of 2015. See https://www.gpo.gov/fdsys/pkg/BILLS-114hr2262enr/html/BILLS-114hr2262enr.htm

  4. The tragedy of the commons” is a scenario referred to by economists. An illustration of this, considered in the nineteenth century, involves an area of common land on which cattle may graze. Each herder, acting rationally, would be inclined to add additional cattle to his herd to gain more from grazing on the land. If all the herders do this, in time the land involved would be overexploited, to the detriment of all. The point is of general application in a wide range of contexts, including the oceans, the atmosphere, the seabed, and so forth.

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Climate Change – What Happens Next?

By Adam D.A. Manning

As a possible apocalyptic scenario, climate change is sometimes ranked alongside, or even superior to, nuclear war in severity.  Headlines tell us that the ever escalating concentration of greenhouse gases in the atmosphere will relentlessly push the temperature higher, unleashing all manner of dangers and adversity, threatening our way of life and harming Earth’s ecosystems. Sometimes it seems so terrifying that we are taken beyond the point of caring and prefer a blissful ignorance as to what awaits us.

For all the doom mongering, it is curious how rarely this striking account of the future is directly related to our own lives or that of future generations. I have two children under the age of ten; what will climate change mean to their futures, or the lives of their children?  Obviously I am concerned as a parent, but more broadly what will climate change practically mean to us as individuals and as a society?

I’ve tried to look into this with an open mind and to use respected sources of information.  It’s obvious that climate change and climate science generally are highly complex.  There is a lot of information available and whilst it is tempting to wish for a simple one page summary, there are so many variables covering such a range of factors that concise overviews are in danger of being misleading.

The most important point in predicting how the climate may change is an estimate of how concentrations of greenhouses gases, the most well known of which is carbon dioxide, in the atmosphere may vary in the remaining decades of the twenty-first century.  If matters continue as they are, with no reductions, the amount of greenhouse gases will increase over time.  By contrast, even if all emissions of greenhouse gases stopped today, the existing levels in the atmosphere will still have some effect on global climate in the years to come.

As a UK citizen, my reading first took me to a report from our government, produced principally by its Met Office (Met here being short for Meteorological) entitled, “UK Climate Projections: Briefing report” from 2010. The Met Office in the UK is a credible authority on climate and the weather. The introduction from Professor Robert Watson, Chief Scientific Advisor, begins, “[T]hat the world’s climate is changing is irrefutable.”  One of the observed trends in the report is that the temperature in central England has already increased by 1°C since the 1970s.

This summary looks at projections for 2080 which are based on what is called a “medium emissions scenario”. This term refers to a projection of how emissions of greenhouse gases will change in the future and the medium emissions scenario is one of economic growth coupled with a moderately reduced use of fossil fuels. It is a middle path between a higher level involving strong economic growth and a lower level in which significant reductions in the use of fossil fuels is achieved.

In this projection, by 2080 the temperature across all parts of the UK will increase, more so in summer than in winter and more in the south than the north.  By that point, the mean summer temperature is projected to increase by 4.2°C in southern England. The figure quoted here is merely the central estimate in a range of values.  This increase in temperature leads to more 10-day dry spells (without rain) throughout the UK especially in southern England and Wales.

Predictions of temperature increase of this sort provide a measure of the forthcoming changes but tell us little of the practical effect on our lives. My reading took me to another report from the Met Office entitled, “Climate: Observations, Projections and Impacts” from 2011 which contained more interpretation of the likely effects.  It noted the additional deaths caused by heat waves and severe storms in the past, the implication being that if these become more frequent, more deaths will occur.

Chapter 3 of the report looks at impact projections of climate change, whilst noting the degree of uncertainty involved.  Strikingly, whilst the UK is presently a country with few concerns about food security, the report suggests in the most severe of scenarios, climate change could affect crop yields, particularly in the south, and that this might, unless managed, lead to exposure to undernourishment.  As the temperature increases and the number and length of dry spells grows, periods of drought and water stress will increase.  The UK, in my experience, responds poorly to droughts (as a rainy nation, we’re simply not used to it) and I can only imagine the difficulties these might cause.

The increase in drought in the summer is accompanied by an increase of the risk of flooding in the winter, due to more rainfall.  The UK has experienced a number of incidents of serious flooding in recent years and these are a disaster for those affected, with homes and possessions destroyed or damaged. The risk is enhanced for coastal areas due to higher sea levels.

The overall picture that emerged was one of a changing yearly cycle with more extreme weather episodes.  The UK always seems to respond poorly to extreme events of this sort and so climate change looks like it would unleash a degree of chaos (and consequent expense) as a result.  And these were predictions from a scenario involving a moderately reduced reliance on fossil fuels.

I was interested to see what research had been carried out on the implications of climate change in the USA and so, naturally, went to the USA’s Environmental Protection Agency’s website. My difficulty was that the temperature changes were all given in °F rather than °C!

Usefully, a section entitled “US Key Projections” set out some headlines that a layperson like myself could absorb.   A temperature increase of a similar nature to that suggested in the UK was set out.  One projection that caught my eye was that, “[C]limate models project that if global emissions of greenhouse gases continue to grow, summertime temperatures in the United States that ranked among the hottest 5% in 1950-1979 will occur at least 70% of the time by 2035-2064.” So, by the middle of this century, temperatures that would have been considered extremely hot during the middle of the twentieth century will be common unless the increase in greenhouse gases is halted.

With regard to precipitation, the EPA predicts that storm tracks in the USA will move northward and the strongest type of winter storms are expected to become stronger and more frequent.  The amount of rainfall in heavy precipitation events is likely to increase in most regions.  Northern areas of the country are predicted to become wetter and southern areas drier.  As the ocean warms, the intensity of Atlantic hurricanes is likely to increase.

The EPA’s website has useful sections exploring the implications of climate change on different aspects of life in the USA.  They state, for example, that, “[C]limate change may especially impact people who live in areas that are vulnerable to coastal storms, drought, and sea level rise or people who live in poverty, older adults, and immigrant communities.”  Also from the USA, NASA has reported that February 2017 was the second warmest February on record in 137 years and that January 2017 was the third warmest January.

Turning to the global scale, the United Nations declared recently that 2016 was the hottest year on record, surpassing the exceptionally high temperatures of 2015. According to the UN, over the 130 year period leading up to 2012, global temperatures increased by 0.85°C.  For each one degree of temperature increase, grain yields decline by about 5 per cent. Wheat, maize and other major crops have experienced significant yield reductions at the global levels during the period 1981 to 2002 due to a warmer climate, a trend that is likely to continue as the temperature rises.

The UN predicts temperature increases by the end of the twenty-first century of a similar nature to that by the EPA and the UK’s Met Office.  At the global scale, the UN stresses that climate change will disrupt “national economies, costing people, communities and countries dearly today and even more tomorrow”.  It can also exacerbate threats such as food and water scarcity, as is already being seen, which can lead to conflict.  This could add to international tensions as nation states respond to these challenges.

This overview of predictions and implications lead me to realise that my curiosity about how, precisely and in detail, climate change would affect the lives of my great-grandchildren (if I am fortunate enough to have any) would only in reality be able to grasp a general outline of the parameters involved. Yet that was enough to get a sense of the profound and swift changes the world might undergo during the lives of my immediate descendants – and my life too of course.

Though wherever I looked there were cautious words about how, even if all emissions stopped now, the climate will be distorted for centuries to come, there were still encouragements about how, at this late hour, plans could be made and action taken to ward away the direst futures. Poorer countries can be helped, in the UN’s words, to “leapfrog to cleaner, more resilient economies.”   The challenge of climate change threatens all peoples and could be the spur to more international cooperation. Time is short though and the need is pressing and more urgent as ever year goes by.  Our children and the children that follow them, the dream and promise of our future generations, need us to get to work right now, today, in doing as much as we can to sort this out as individuals, countries and a world.

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Space Based Solar Power – the key to a bright future?

By Adam D.A. Manning

Solar energy directly beamed to Earth’s surface from space has for over fifty years been proposed as a cheap and endless source of energy.  In more recent years, this Space Based Solar Energy (SBSP) has also been suggested as a way to tackle climate change by weaning us away from fossil fuels. Yet for all its perceived usefulness, the practical implementation of such plans is as far away now as it has ever been.

solar_panel_satelliteOriginally proposed by Dr. Peter Glaser in 1965, the concept involves satellites in orbit converting solar energy from our Sun and converting this into a form that is then transmitted down to a receiving station on the Earth’s surface below, either by microwave or laser transmission. The advantage over solar panels on Earth is that solar energy in space is effectively continuous; the weather or the day/night cycle cannot interfere. Without the barrier of the atmosphere, solar energy is more powerful as well.  SBSP seeks to directly tap the endless and enormous energy of our Sun and put it to use here on Earth.

This startling idea could provide a way to break our civilisation’s dependence on fossil fuels and to reorder the geo-political relationships derived from our petroleum based economy.  SBSP received more attention during the 1970s and in particular became associated with the studies on large-scale space habitats undertaken by Dr Gerard O’Neill.  Analysis at the time indicated that to really make an impact, the structures in space required by SBSP would have to be enormous.  Satellites with arrays of solar panels over a kilometre in diameter were outlined in the more far-sighted reports.  These issues were seized upon by critics and the concept became somewhat discredited.

sbspdemorenderIn the decades that have followed, new studies have returned to the idea. The tantalising prospect of cheap, abundant energy means interest has never entirely disappeared.  One common theme is that no fundamental breakthrough in science is required to deliver SBSP; the challenges are those of scale and cost.  As well as the huge infrastructure required, another issue is the very large number of launches from Earth that would be required and their resultant costs.  One suggestion on how to tackle this is to use materials taken from the Moon’s surface as the building blocks for the power satellites, thus cutting down on the number of launches from Earth’s high gravity well.

the-case-for-space-solar-power-coverMore recent consideration focuses on the use of new techniques and technologies to reduce the costs required in creating a viable SBSP system.  The original studies envisaged armies of workers in space being required to assemble the power satellites; modern studies note how robotics can be used instead, especially when combined with 3D printing techniques.  John C. Mankins’ book, The Case for Space Solar Power is an accessible and fascinating look at the development and current state of studies on SBSP.

Practical experiments related to SBSP have taken place, for example in Japan.  This involves the beamed transmission of energy over a distance of over fifty metres.  If SBSP is to move forward, experiments in space are needed to prove the technology involved. An example of this could be a power satellite, somewhat smaller than the eventual structure at only 50 metres in diameter, being placed in geosynchronous orbit and beaming down power to a collecting station on the surface below.

The promise of SBSP is potentially a world wide revolution in energy creation.  SBSP could offer clean, continual power at very little cost, once the enormous installation required is in place.  Freed from needing fossil fuels, our civilisation can potentially step away from additional carbon loading of the atmosphere.

Yet there are many counterpoints to be made.  Elon Musk, of Tesla and SpaceX fame, takes the view that SBSP is impractical as, in his view, by the time SBSP derived energy has been partially absorbed by the atmosphere and is received, the level is not that much different from conventional solar panels placed on Earth’s surface. The suggestion is that it would be cheaper and more efficient to obtain all the energy SBSP might provide by an appropriate number of conventional solar panels on Earth’s surface instead.

sbspdemoframeAs well as the power satellites, which would still be very large even with the application of modern techniques, the receiving stations on Earth would be huge as well.  To collect the radiation at ground level will require stations that are estimated to be, again, over one kilometre in diameter. The safety of the microwave or laser transmissions to Earth from the power satellite is also another key issue. Advocates suggest these would be at such a low level that it would be safe for birds or aircraft to fly through; opponents are not so sure.

The issue of cost is the most important factor in deciding if SBSP is viable and, as with safety, opinions are divided.  It seems that launch costs are a key here. These never did reduce as dramatically as the studies from the 1970s predicted.  The analysis must focus on whether SBSP derived electricity is cost effective compared to that from other sources, such as nuclear power stations.

The potential for answering both our ever-growing energy needs and the escalation of climate change will renew interest in SBSP. Such a huge project requires government intervention, yet it remains to be seen if democratic governments elected every semi-decade or so can implement such a substantial plan and see it all the way to fruition.  It is interesting to note that the Chinese government is studying SBSP as a possible means of tackling its pressing energy needs.  Perhaps what is needed is a race, like the Moon race of the Apollo years, to finally see SBSP leap off the drawing board and into orbit.

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Wildlife in your Neighbourhood

By Adam D.A. Manning

It’s all too easy to think of wildlife as something that lives somewhere else. Living in a built up area, we can imagines ourselves as inhabitants of an artificial, purely human environment. Yet nature is all round us all the time, no matter where we are and even in urban areas, there is often a great deal of non-human living matter, especially plant life.

It’s all too easy to take the living world around us for granted, to not even notice it and to consign nature to designated parks, zoos or far off lands.  This neglects the riches of the ecosystems lying close at hand, sometimes unheeded for years. Near where I live in England is a beautiful beach called Weston Shore that is often thought of as a simple stretch of pebble-strewn shoreline.

learning-about-sea-purslaneThrough a local community group that I belong too, we’ve been in contact with a professional ecologist called Phil Budd and he’s been kind enough to take us on guided walks along the shore.  An amble like this with Phil is a revelation. Even early on in our trip to the beach, his knowledge wakes you up to how the plants and animals in your local area form part of an ecosystem as vibrant and intricate as any tropical jungle or temperate forest.
bladderwrackOn the tide line at the shore is a common type of seaweed called bladderwrack.  This is a habitat for the imaginatively named Seaweed fly and these flies in turn are eaten by some of the birds that visit the area. Those birds in turn are eaten by birds of prey like the sparrowhawk. Similarly, a beautiful plant called sea purslane is a habitat for insects such as the lesser marsh grasshopper, which again leads to higher steps in a food chain.

sea-beetI was intrigued to learn that a number of the plants on the shore are perfectly edible (subject to washing, boiling or steaming as appropriate).  Sea purslane goes well with fish, for example, or in a salad. Another common plant on the shore is sea beet, the wild ancestor of plants such as beetroot, sugar beet and Swiss chard.  It can be eaten cooked or even raw – although none of us were brave enough to try it there and then!  Other plants found on the shore can be used in herbal teas or as remedies.  These plants have the potential to be something of a treasure trove to foragers.

An interesting subplot to Phil’s description of the animals and plants were that a surprising number of them were ones that had been introduced to the area by human activities, such as the Manila Clam. Originating in Asia, this was now quite happily living on our English coasts.

We’ve had some fascinating and fun visits to the shore and we’re looking forward to more. To have such a familiar area opened up in this way is an exciting look into a new world of knowledge.  As well as finding out about similar experiences in your area, it is also possible to download apps that can help identify trees and plants and there are plenty of books and online guides on the subject as well.  The riches of the natural world are there for everyone to enjoy and to marvel at.

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A New Home on a Bright Moon

By Adam D.A. Manning

Humanity has the potential to become the agency by which life from Earth radiates out into the cosmos – the rest of the Solar System and then the stars beyond.  This is the most exciting role in the universe for us, the most optimistic future for our species.  Far from a curse to life on Earth, we would become one of the most extraordinary chapters in the story of evolution, on a level with the first of the multi-cellular organisms, the fishes crawling onto land or the birds taking to the air.

That might be the lofty, inspiring vision but in the here and now, extending business into space seems to be of interest to several very rich citizens. Billionaire Elon Musk, of Tesla and SpaceX fame, is planning a large scale settlement on the red planet, Mars. Our sister world, the Moon, has been getting some attention as well with Amazon’s Jeff Bezos talking about building a base there and Virgin’s Richard Branson setting himself the long term goal of a lunar hotel.

earth-from-lroIn his announcement about his plans for Mars, Musk listed advantages that the red planet has over our Moon.  Yet it is clear that, as both a stepping stone to further exploration of space and a destination in its own right, Luna (another name for the Moon, which I prefer) has some very practical advantages.  It is of course, much, much nearer than Mars.  The Moon is about 384,000 km (239,000 miles) distant.  At its nearest, Mars is 55 million km (34 million miles) away; that is around 143 times the distance to the Moon.  As it circles the Sun in its own orbit, Mars spends a lot of time much further from Earth than that.

This nearness and the much lesser degree of variation in that distance makes the Moon enormously easier to get to than Mars.  The last humans to walk on the Moon did so in Apollo 17 in December 1972 and so there is a lot of experience in getting out to lunar distance. In comparison, many of the robotic missions to Mars have failed to successfully reach their goal.

Lunar regolith, that is its soil, is known to contain many elements needed for space construction, life support and rocket propellant.  Its top three elements are oxygen, silicon, and iron and it’s a useful resource for exploration deeper into space. The gravity on Luna’s surface is only one sixth of Earth’s and so launching into deeper space from there requires much less energy than from Earth.  Luna makes an ideal staging post for missions into deeper space as a result.

As regolith can be a useful material in constructing structures in space, handily an efficient means exists to propel it from Luna to where it is needed. This is called a mass driver, which is essentially a large, electro-magnetically powered catapult.  The mass driver is a large loop on Luna’s surface.  Containers with a payload of regolith move round the loop at increasing speed, until the contents are fired into space and ultimately out beyond Luna’s gravity to the construction site.

This system has the potential to yield large quantities of material that can be used for building space borne facilities, including factories and much larger space habitats than the International Space Station.  It is inconceivable that launches from Earth could ever provide the same quantities due to the far greater energy required to escape Earth’s gravity compared to the Moon.  If a substantial human expansion into space is to take place, the mass driver is a key component in building the infrastructure required and is the most important reason why the development of the Moon should be a priority.

Water on the Moon will also provide a useful resource to visitors and settlers; not only for drinking and plant propagation but, after being split into hydrogen and oxygen, could help provide a breathable atmosphere and rocket fuel.  This water has been detected in particular in the polar regions and may have been deposited by comets impacting the surface.

In the further future, another element found on the surface might be of use to explorers and settlers in providing power.  To date, all practical forms of peaceful nuclear energy have been fission powered, that is releasing energy by breaking atoms apart.  A more powerful and possibly less risky form is nuclear fusion, which, like the Sun, creates energy by fusing the centres, or nuclei, of atoms together.

A lot of excitement has been caused by the use of Helium-3 in nuclear fusion power plants as it has the potential to be a very efficient process.  One drawback though is that Helium-3 is rather rare on the Earth’s surface. It turns out that it’s more common on Luna’s surface, as it has been embedded in the regolith by the solar wind over billions of years. Settlers might harvest Helium-3 from the regolith to power nuclear fusion generators that provide energy to their outpost.

apollo-16My last entry in this list of advantages is solar energy. Luna is on average the same distance from the Sun as Earth, but its atmosphere is so tenuous that it may as well be described as a vacuum. The solar energy hitting a panel on Luna would be more than that on Earth as a result. Mars on the other hand is further away from the Sun than either Earth or Luna and so the solar energy it receives is rather less.

Admittedly, Luna’s day of slightly more than 27 Earth days means that for long periods of time, a given hectare of the lunar surface will be in darkness. Solar power satellites can be placed in lunar orbit and they would transmit the power between them to where it was needed.

There are certain mountains on Luna’s surface that receive sunlight on an almost constant basis. These areas, referred to rather poetically as peaks of eternal light, would be particularly useful to settlers as they could supply virtually uninterrupted solar energy.

Luna is well placed and constituted to act as an initial resource for much greater levels of human expansion beyond Earth.  Drawing on the heroically won experience of the Apollo missions, we can learn so much from going there and developing lunar bases and ultimately settlements.  There will be invaluable lessons for further exploration deeper into space including, in time, Mars.  Human missions to the red planet will be strengthened and emboldened by this, ensuring that the long-term settlement of Mars has a much greater chance of success.

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An Environmental Issue We Can All Clear Up

By Adam D.A. Manning

The Earth is doomed. We are doomed. There is nothing we can do and it is not worth even trying.

How easy it is to feel like this! Pushed up against sheer cliffs of despair by the mass of headlines about our world’s environmental dangers, we are squeezed into a narrow ravine of thought. Only think of now and here and, whatever you do, don’t think of future times and the lives of our children, their children and those to come afterwards.  The unceasing destruction of biodiversity, the loss of natural habitats, deforestation, desertification, pollution and the most inescapable and insidious of all – climate change; no wonder we find it difficult to think of taking action.

The most serious environmental dangers challenging life on Earth, global in extent, have profound implications for humanity and the lives that we lead.  While we can take action as individuals to help, these have to be tackled at a national and international level for substantial progress to be made. Yet there is one serious environmental problem that is easy to tackle, where progress can be made right now and the results are immediately obvious.

IMG_9716This is litter – the curse of modern living; something that is so ubiquitous we often fail to consciously register it is there.  Litter is usually all round us everywhere – a seemingly inevitable by-product of the sublime efficiency of our industrial world culture.  Yet there is a growing movement, assisted and inspired by the internet’s rapacity for communication, that aims to face up to this incessancy.

This is not, by any means, to suggest that litter is a trivial and unimportant challenge.  Most obviously, litter is unsightly and spoils views and vistas that might otherwise let us soar with inspiration.  It’s difficult to let yourself go and feel at one with the beauty of nature if drink cans, chocolate bar wrappers and packets for snacks are scattered everywhere.

At a human level, a litter blight in an area has been shown to be linked to increased levels of crime. For instance, a study by Keep Britain Tidy in 2014 showed that areas with poor levels of cleanliness were associated with criminal activity and social disorder.  Conversely, places with low levels of litter, fly posting and graffiti were also those least at risk from crime.  It seems that tackling litter can lead to changes in the human environment.

IMG_6936As an environmental issue, litter can have devastating effects on wildlife.  There have been videos and photos of turtles with plastic forks and straws stuck in their noses. A dramatic case is that of Peanut, a red-eared slider turtle, who became stuck in a six-pack can binder as a youngster and grew up deformed as a result.  Not only did this affect the turtle’s internal organs, it would have also made her more vulnerable to predators as it affected her mobility.  Similar cases involve pelicans, albatrosses and other sea birds.  Recently, thirteen sperm whales that died after becoming stranded on a beach in Germany were found to have stomachs full of plastic.  Seals can become caught up in old rope, netting or fishing line and drown.

Fox cubs get their heads caught up in discarded wheel hubs and hedgehogs get their heads trapped in tins. At a smaller scale, lizards can fall into cans left discarded in habitats, never able to get out.  Gum, spat out somewhere, can end up matting an animal’s fur, making it difficult for them to move freely in forests and potentially trapping them.

Many of us will have seen videos showing remote islands, where the beaches are strewn with plastic debris from our civilisation.  Areas of the Pacific Ocean are, due to a coincidence of currents, floating assemblages of human rubbish.

Our pets can also be at danger from litter.  Cats have been caught in drink can binders as well and dogs have had their heads trapped in jars.  Animals choke on discarded balloons, sometimes the debris from mass balloon releases.

autcleanupadamThankfully, litter’s very visibility has lead to many people wanting to take action.  Groups all over the world regularly carry out litter picks and clean ups and it’s no surprise that these have become popular in recent years.

I’ve been part of a group that has for around twenty years carried out regular beach clean ups on Weston Shore in Southampton, England and can attest to how satisfying it is to get involved.    A litter pick, either solely or with the help of friends, can quickly transform an area.  The results are immediate – simply look back at where you’ve worked and see how much cleaner it is.  There are other benefits; fresh air and (possibly) sunshine, a little gentle exercise from walking around, taking in the sights, getting out in your neighbourhood and taking part in the life of your community. It can also be very sociable and a lot of fun!

elizabethandalisonLitter picking as an activity has grown in popularity in the age of social media.  It is often a very visual subject for the camera and sometimes can be rather bizarre.  Diamond (or more likely, fake diamond) studded dog collars, bits of alarm clocks, toys of all descriptions, innumerable golf balls, parts of cars, the complete range of types of clothing – all have been found on litter picks.  This makes for a good subject for instagramming, tweeting and so forth.

One group that have really picked up on this idea is Litterati. Focussed on instagram, the idea is to take a shot of litter and then tag it, #litterati.  This has become a global hit with, at last count, over 227,000 pieces of litter tagged and cleared up.  As a regular beach cleaner, my favourite tag is #brandsonthebeach.  So many of our popular brands, Coca Cola, Budweiser, Irn-Bru, Red Bull, and so forth, end up as rubbish on our beaches or in our natural places. Let’s show them how their precious products really end up.

FOWS8A similar movement is #2minutebeachclean.  The idea here is to do a little and often. A two minute clean up really can help and spreading the meme helps more get done.

To see an area you’ve cleaned up, with just a little effort, is so rewarding. It’s not just good for the planet, it’s good for you too. A wonderful friend of mine has told me how therapeutic and soothing he finds litter picking to be and I believe him. Who knows, maybe there is a similar activity in your local area?
IMG_6915With a sense of achievement from this type of activity, facing up to the greater challenges seems more reasonable.  If we can make a difference here and now, maybe making a difference with these more profound difficulties is not so impossible.  Just maybe, there is good reason to hope after all.

 

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An Armchair Astronomer No More

By Adam D.A. Manning

The glitter of a clear night sky has always entranced us. Even in these days of extraordinary knowledge about the affairs of the cosmos, it is still easy to look up and lose yourself in its illimitable mystery and wonder.

Many of us have a fascination and thirst for knowledge about the planets, the stars, the galaxies. This great intrigue is easily inflamed by the lore to be found in books and it is exciting to get involved in practical, hands on astronomy as well. In an adventure into this more direct experience, my wife and I paid a visit one starry evening to the Toothill Observatory near Southampton in England, run by the Solent Amateur Astronomers.

The group was welcoming and keen to share their knowledge of and passion for Space. They had a large telescope permanently installed and, looking through this, we were able to view Jupiter, the largest of the Sun’s planets, accompanied by four of its largest moons, those being Io, Europa, Ganymede, and Callisto. Books on astronomy are often replete with breathtaking photographs of celestial beauty, including of course the planets and moons of our solar system. Yet to see the disc of Jupiter with your own telescopically aided eye, that lovely marble colouring and the banding of the clouds, took the experience off the page and gave it a sudden, absorbing immediacy. Here was the king of the planets, and I was looking at it right now (or at least as it was rather more than thirty minutes ago, given the time that light takes to travel from Jupiter to Earth).

The four largest moons of Jupiter are collectively called the Galileans, and they sparkled and glinted as they lay in a perfect line, three on the right and one on the left of Jupiter at the time of our visit. When they were first discovered in the early seventeenth century, they helped prove that telescopes were of the greatest assistance to scientists, as they could show objects that were too far away or too small to be seen with just the eye. These moons had never been observed prior to the invention of the telescope.

Other telescopes were accessible at the observatory as well and we were able to gaze into the depths of the Pleidaes star cluster. Our visit to Toothill Observatory had been unexpectedly exciting and I was delighted when, later, a friend very kindly gave me a telescope he no longer had a use for. With this I could have my own adventures with astronomy.

Setting up the telescopeThe specific model was a Bushnell 78-9003, which appears to be quite representative of the type of telescope that can be purchased relatively inexpensively for use at home. Examining it, my first impression was of how beautiful this instrument was, the shining chrome and circular lenses arranged in a mathematical perfection. I’m not naturally a practical person by inclination, so carrying out the assembly work that was required was an enjoyable challenge.

Once completed, the telescope was put in the back garden. The next step was to aligning the Finderscope, the small tube sitting on top of the main cylinder, with the telescope. I was a little self-conscious of swinging the telescope about in the back garden, wondering if my alarmed neighbours might think I was spying on them. In the end I settled on using the top of a clothes’ line stood in a neighbour’s garden, some three houses down the road, as a target for this purpose.

Telescope1It looked large enough in the Finderscope, but when I used the low power 20mm lens in the main telescope to view it, I had a shock. The top of the post had a rubber stopper on it. In the eyepiece of the main telescope, this was so close I could see every wrinkle and crease in the stopper’s orange surface. This magnifying power was impressive! I could easily imagine how astonished the telescope’s original inventors might have been.

I was keen to get star-gazing (or at least moon-watching) and it took forever on that long summer evening for it to be sufficiently dark. Eventually I was able to step out into the dark and swivel the telescope round roughly in the direction of the full moon that shone that night.

At first there was a little light cloud near the horizon when the Moon first appeared, which rolled and whisked across the lunar circle rather dramatically. This made getting a good look rather difficult. After waiting a little longer, this cleared and the Moon climbed higher in the sky, making a viewing much easier.

Telescope2One thing I noticed immediately was that a telescope such as mine is very sensitive to the slightest touch or wobble. Whenever possible, I tried to lock it into position as much as I could to prevent this, but this proved somewhat tricky. The act of tightening the telescope’s adjustment screws could move the main eyepiece off target. Looking through the eyepiece had to be done delicately as pressing too hard could easily move the telescope the tiniest fraction, thus taking the view off the Moon.

A certain degree of patience paid off as the skills needed to keep the telescope on target whilst focussing developed. My admiration for the experienced astronomers at the observatory grew. With a little persistence, I was able to train the main telescope onto the disc of the Moon’s surface and beheld it in all its magnificent desolation (to use Buzz Aldrin’s celebrated description). The long stretches of the intense whiteness of the highlands were a skeleton around the darker, almost cyan shaded seas and with the lightest of touches I could gaze over the different quarters of our lovely sister world, the Earth’s quiet and constant companion.

The stark glow of Luna and all the intricate detail arrayed for us in its circle in the sky is a gift to the novice astronomer. I spent a lot of time pouring over the Moon and only later thought to try the higher power 4 mm lens that I had been given as well. Impatiently fitting this, I sought once more for the lunar surface but, sadly, had no luck at all. I am not sure how it was what that I could miss the Moon, given that it would be so much larger in this higher magnification. It must have been down to my inexperience.

After a frustrating twenty minutes spent in this way I yawned and suddenly noted how late it had become and how cold I was, stood in my garden at 1.30am with just shorts and a t-shirt on from the earlier balmy summer evening. Turning in for the night, I promised myself that I would continue my adventure into astronomy. In particular I am excited about learning how to find and look upon the planets and their moons. My hope is that this account of my first steps in astronomy may encourage others as well.

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The Solar System In Motion

By Adam D.A. Manning

In ancient times, it used to be thought a matter of common sense that the Earth was stationary and that the planets, the stars and the Sun all moved around us. As we stand on the Earth, it seems immeasurably, or at least hugely, wide in all directions horizontally. The general perception of many was that this size alone, this weight, meant the Earth was immovable and the night sky was a sphere or even series of spheres, sometimes poetically thought of as being of perfect crystal, arrayed around our world, the centre of all things. In this geocentric model, the days are caused by the revolution of the Sun about the Earth. This conception of the universe suggests that everything is arranged for us. We are the centre of all things and what happens here and what we do is of supreme importance, the universe seems to be telling us.

The modern conception of the true arrangement of the Earth and the other elements of the Solar System dates from the Renaissance in Europe. In the mid 15th Century, Nicholas Copernicus famously set forth our modern view, that of a heliocentric system in which the Sun is at the centre of the Solar System and the Earth and the other planets revolve in orbits around the Sun. Think of the extraordinarily profound realisation that the days are caused by the rotation of the Earth and not the revolving of the Sun around us. In a few pages, the Earth has been reduced to one of several bodies circling the Sun and we are no longer at the most important and unique place in the cosmos.

jupitergalileoThis theory was elaborated upon by Johannes Kepler in the early 17th Century, who, after more careful observations, deduced the proper shape of the planetary orbits, which was that of the ellipse. An ellipse can be viewed as a circle as seen from an angle. The perfection of the cosmos was starting to shatter with the realisation that not even the orbits of the heliocentric system were purely circular as previously believed. Galileo, a few years later and using the recently invented telescope, noted four moons in orbit around Jupiter and this was further proof that the Earth was not the centre of all things.

Many of us will have a picture of the layout of the Solar System as a series of concentric circles of increasing size, with the Sun at the centre. The normal view is of a static, disc shape, as if the orbits are the grooves in an LP record (if you can remember what that was!) and the Sun is the hole in the centre. This is generally adequate when thinking purely in terms of being within the Solar System but our Sun and its attendant planets and their moons are part of an immensely bigger structure; the Milky Way Galaxy.

Far from this static model, the Sun is orbiting the centre of our galaxy at great speed and taking the Solar System with it. Although it takes an enormous period of time, roughly 225 million years or so, to carry out one orbit of the centre of the galaxy, the distance involved is so huge that it is doing this at an enormous speed of 230 kilometres per second. So, the picture then is of the planets orbiting the Sun as the Sun itself is hurtling around its orbit. As a result, the static picture of the Solar System as a disc is only partially correct; the disc itself is moving as well.

An interesting thought experiment is to imagine the track or trail of the planets as they circle the Sun whilst the Sun moves ever onward. Taking up this challenge, I decided to try to model this on my computer with a 3-D graphic package.

This became a fascinating project and the first step was to get some good data on the size of the planet’s orbits. In this day and age of the Internet and wikipedia this was a moment’s work. As soon as I started this, one of the key features of the arrangement of the Solar System became apparent. The four inner planets, Mercury, Venus, Earth and Mars, all have evenly spaced orbits. If you try to keep them visible at the same time, the four outer planets of Jupiter, Saturn, Uranus and Neptune are much more widely spread out. Trying to view the whole Solar System means that the four inner planets’ orbits are very small, barely discernable ellipses close to the Sun. That is why astronomers often talk about the inner Solar System, in which we reside, and contrast this with the more far-flung outer Solar System.

Another feature of trying to display the Solar System in this way is that the planets, even the large gas giants like Jupiter and Saturn, are tiny compared to the size of their orbits. If you really were to draw the planets at the same scale as their orbits and fit it all on one computer screen, it would be very difficult to see them. You might see the Sun as a bright pixel in the centre and fleetingly you might glimpse the gas giants, but that would be it. To aid the viewer, you have to have a different scale for the size of the planets compared to their orbits.

As I worked on this, I was eventually able to simulate the orbits of all eight planets as they revolved around the Sun, as the Sun in turn moved forward through the galaxy. I kept it simple in a number of ways. Firstly, each planet’s orbit is inclined at a slight angle that is different for each planet. In other words, each of the orbits are in a different plane compared to the others, that all intersect (roughly) about the Sun. By and large however, the inclination of the orbits is relatively small so I ignored this point. It would be difficult to notice this on my simulation in any event. In addition, as noted above, the orbit of each planet is not a true circle but is an ellipse. In practise however, they are near enough to a circle to make little difference at the scale of my simulation and again it would be difficult to notice this point.

The exception to these points is Mercury. The angle of Mercury’s orbit is a little larger than the other planets and is also a more pronounced ellipse. I decided to not take this any further though as Mercury’s orbit is very small compared to the other planets, especially the outer ones, so that again it would be difficult to notice this.

Another interesting point about the orbits of the planets is that we generally think of them as being centred on the Sun. An ellipse has in fact what you might think of as two “centres” and these are called focal points or focuses. One of the focuses of the Earth’s orbit, for instance, is within the Sun. But it is not, as might be thought, in the exact centre of the Sun. Instead, when a planet orbits a star, they both orbit the centre of mass of the two of them. As an example of this principle, imagine two planets of the exact same mass and density and so forth orbiting each other. They would orbit around the centre of mass between the two of them.

With the Earth and the Sun the situation is a little different. The Sun is so hugely massive compared to the Earth that one of the focal points of the orbit is within the Sun itself, albeit not actually at the Sun’s exact centre. The same holds true for all the other planets apart from Jupiter. Jupiter is so massive that the focal point of its orbit is just beyond the Sun’s surface. As a result, the Sun orbits this point and so if you studied the Sun very carefully, you would notice it revolving around a point just beyond its outer edge.

This “wobble” is one of the ways astronomers use to determine if other stars have planets orbiting them. If they are suitable massive compared to their star, they may also pull the star around in a similarly tight orbit.

This effect was so small that I felt there was no need to include it in my simulation as again it would be very difficult to see this on a scale that involved the orbits of all the Solar System’s planets.

After running it, the simulation produced some beautiful spiral shapes as the planets orbited the Sun as the Sun itself orbited the centre of the galaxy. Of course, my simulation had to run at a much higher speed than the real Solar System. After all, it takes a whole year for the Earth to orbit the Sun and at that speed, the little sphere on my screen representing the Earth on my screen would move slower than the hour hand of a clock! So, in the end I settled for each minute of my simulation representing roughly twenty years of real time.

One final point was the angle of the Solar System as it proceeds in its orbit around the centre of the galaxy. It was tempting to assume that it was horizontal or vertical compared to this movement, but in fact it is tilted at sixty degrees to the direction of its movement around the centre of the galaxy. This means that some of the planets may be ahead of the Sun in its orbit whilst the others are behind it. As the planets’ orbits progress, these relative positions switch around. Think of somebody with an umbrella in the rain who has to angle the umbrella slightly forward to account for the wind as they walk and you get the picture.

Watching the simulation was quite entrancing. The intertwining spirals (or helixes as they should be called) were a manifestation of nature’s uplifting beauty. I soon realised that I had in fact missed one further point. In creating my simulation, I had simply assigned a value to the speed of the Sun’s orbit around the galaxy’s centre that was convenient and seem to make for an interesting result. I had not actually considered what this ought to be.

By entering the correct value of the speed of the Sun’s orbit, I realised that the Sun, along with the rest of the Solar System including the Earth, were orbiting the centre of the galaxy at a rate far greater than the speed of the Earth’s orbit around the Sun. For instance, in a year the Earth will travel roughly one billion kilometres as it revolves around the Sun. In the same time however, it will have travelled around seven billion kilometres as the Solar System orbits the galaxy’s centre.

This changed the look of the simulation rather markedly. Although the helix shapes are still there, they are much more elongated. In fact, the overall impression now is that the track of the movement of the planets are long streamers or tails stretching out around the Sun. This was an unexpected result and added an element of discovery into what had already been a fascinating and absorbing project.

To make the simulation more sophisticated, the points referred to above would have to be added in. In addition, at the scale shown in my animations, the movement of the Sun is as near to a straight line as makes no difference. Yet for it to be accurate this ought to be taken into account.

In addition, the orbit of the Solar System around the galaxy’s centre is not a flat a plane. It oscillates gently up and down, roughly four times during one orbit. A further simulation could show this as well to make the picture more complete, although again this motion is so enormous that at the scale shown in my simulations it is unlikely that you will be able to see this.

I had learned a great deal from this project. As with the movement from a geocentric to a heliocentric model of the Solar System, the incomprehensible expanse of space and our world’s minute dimensions in comparison are the impressions one is left with. Our precious, beautiful planet is a tiny, living pin point in the enormity of the dark and we are so lucky enough to briefly exist on this shore of the cosmos.

A vlog that contains the animations I created as part of this project is set out below – please do take a view!

videotitlej

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