Tag: Milky Way

Why is intelligent life so rare?

Maybe it is because of a ‘Great Filter‘.

Like so many others I read many items online. One of the websites that I follow is the EarthSky site because for a long time I have been interested in space.

So when I saw an article on why intelligent life is so rare in our Milky Way I read it fully. And hoped it would be of interest to others.

Here it is:

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What is the Great Filter, and can we survive it?

Posted by

Kelly Kizer Whitt and Deborah Byrd

November 17, 2022

This graphic depicts intelligent civilizations as stars. The vertical lines represent Great Filters that civilizations do or don’t survive. This graphic depicts Earth’s human population (the yellow “star”) approaching its own Great Filter. How would we surpass it, and keep going? Image via NASA/ arXiv.

What is the Great Filter?

Is intelligent life common, or rare in our Milky Way galaxy? If it’s common, why haven’t we encountered it? While discussing UFOs on a walk to lunch in the year 1950, the physicist Enrico Fermi is famously said to have asked, “But where is everybody?” Scientists today call that riddle Fermi’s Paradox. Now a new paper by NASA scientists explores one possible answer to the paradox. The answer may be what’s called the Great Filter.

Economist Robin Hanson first proposed the Great Filter, in the late 1990s. It’s the idea of that – even if life forms abundantly in our Milky Way galaxy – each extraterrestrial civilization ultimately faces some barrier to its own survival. The barrier might come from without (for example, an asteroid striking a planet, and wiping out all life forms). Or it might come from within (for example, all-out nuclear war).

Hanson proposed that a Great Filter might be at work within our Milky Way galaxy. He argued – from what we can see here on Earth – life expands to fill every niche. And so, he argued, we should see signs of intelligent life beyond Earth in nearby star systems, perhaps even in our solar system. But we don’t see this.

Is humanity facing a Great Filter?

The authors of the new paper take Hanson’s idea further. They explore the idea that humanity may now be facing a Great Filter. The authors wrote:

We postulate that an existential disaster may lay in wait as our society advances exponentially towards space exploration, acting as the Great Filter: a phenomenon that wipes out civilizations before they can encounter each other … In this article, we propose several possible scenarios, including anthropogenic and natural hazards, both of which can be prevented with reforms in individual, institutional and intrinsic behaviors. We also take into account multiple calamity candidates: nuclear warfare, pathogens and pandemics, artificial intelligence, meteorite impacts, and climate change.

And they offer solutions, beginning with, as they say:

… a necessary period of introspection, followed by appropriate refinements to properly approach our predicament, and addressing the challenges and methods in which we may be able to mitigate risk to mankind and the nearly 9 million other species on Earth.

In a sense, the authors of the new paper – including lead author Jonathan H. Jiang of NASA’s Jet Propulsion Laboratory in Pasadena, California – are engaging in a “necessary period of introspection” by the act of writing their paper.

And, with their paper, they’re laying out the challenges we’re facing and methods of addressing them.

We’ve already survived some ‘filters’

The scientists point to life’s resilience. Life on Earth has already survived a number of filters in the form of mass extinction events. The Permian-Triassic extinction – aka the Great Dying – occurred 250 million years ago and nearly ended all life on the planet. This extinction event wiped out about 96% of marine life and 70% of land species. The exact cause of the Great Dying is still a matter of study, but some scientists have said it was a combination of warming temperatures and decreasing oxygen.

But these previous filters, or extinction events, have been natural, arising from the evolution of our planet and solar system, including volcanic eruptions and asteroid impacts.

A Great Filter of our own making

But now, clearly, humanity may be facing a Great Filter of our own making, and one that other intelligent civilizations in the galaxy have faced … and failed to withstand. Perhaps it’s no surprise that the technological advancements humans have achieved might ultimately lead to our undoing. Perhaps that’s nature’s way. As the new paper said:

It seems as though nearly every great discovery or invention, while pushing back the borders of our technological ignorance, is all too quickly and easily turned to destructive ends. Examples such as splitting the atom, biomedical innovations and resource extraction and consumption come to mind with disconcerting swiftness. Still, some have suggested artificial intelligence (AI) as yet another factor, which, pending substantial technical hurdles, may yet have its chance to prove friend or foe.

Here’s a look at some of the issues that might compose Earth’s Great Filter.

Unchecked population growth

One of the factors Earth faces, according to the paper, is unchecked population growth. Earth just passed a milestone on November 15, 2022, when it reached 8 billion human inhabitants. The paper said with our current population figures, Earth has experienced:

… an exponential rise from about 1.6 billion [people] at the start of the 20th century.

Technological advancements in farming, energy production and distribution have made such a large population possible on Earth. But, as the paper said, these advancements cannot:

… indefinitely offset the multifaceted stresses imposed by an ever-escalating population.

When will Earth’s human population reach its peak size? Some projections report that education in developing nations might allow Earth’s population to peak at 10 billion in the 2060s. But, of course, no one really knows.

Nuclear war

While warfare has long been a factor of life on Earth, only in the past century has humanity had a weapon that could destroy all nations, not just those participating in a nuclear war. The scientists said the greater the number of democracies in the world, the better our chances for avoiding nuclear war. The scientist also saw other encouraging signs, including:

Peace agreements in the historically troubled Middle East, a vast reduction in nuclear warheads since the height of the Cold War and a wide coalition of nations rallying their support for the besieged in Eastern Europe.

Pathogens and pandemics

The threat of illness and pandemics continues to grow simply because our world is so interconnected. Spreading diseases have a much easier time in our global society. But on the positive side, advancements in medicine have also given us an edge. The scientists said that having current and reliable data is crucial:

… in predicting how future pandemics will spread, how deadly they will be and how quickly and effectively we will be able to leverage our knowledge of the life sciences to counter this manifestation of the Great Filter.

Artificial intelligence

While true artificial intelligence as a separate sentient being is not yet reality, the authors of the paper urge a proactive plan to peacefully share Earth. They project that computer sophistication will one day rival that of the human mind. The scientists said:

As for whether AI would be benign or otherwise, self-imposing a Great Filter of our own invention, that will depend on the evolving nature and disposition of Earth’s first high-tech species.

Asteroid and comet impacts

Here’s an extinction event from the past that could still spell our doom in the future. While large impacts are exceedingly rare, there is, as the scientists said:

… a non-zero percentage [of asteroids or comets] which are large enough to survive passage through the atmosphere and, impacting the surface, cause catastrophic destruction to our sensitive biosphere.

The odds of a mass extinction level event in the coming years is vanishingly small. But, over time periods extending into the very distant future, the odds increase toward 100%. Meanwhile, with projects such as the DART mission, and given enough lead time, humanity has a way of defending itself.

Climate change

Climate change has become one of the most studied threats to life on Earth. Because the threats from climate change happen on a slower time scale than, say, the time it takes to launch a nuclear weapon, the efforts to curb these effects have not been as rapid as they could have been. The scientists said:

The major impediment to taking more decisive actions, however, are the challenges imposed by transitioning to non-carbon-based energy sources such as solar, wind, nuclear power. Here again, rapidly advancing technologies in areas such as modularized nuclear power plants and carbon capture and sequestration (CCS) are among the best hopes for avoiding slow-motion ensnarement by this lulling but lethal Great Filter.

Avoiding the Great Filter

So you see there’s not just one possible Great Filter for Earth, but many. Any one of them could be our downfall. These scientists are suggesting something that sounds simple on its face, but is (apparently) hard to do. That is, in order to avoid the Great Filter, humans must work together and recognize the big picture. As the paper said:

History has shown that intraspecies competition and, more importantly, collaboration, has led us toward the highest peaks of invention. And yet, we prolong notions that seem to be the antithesis of long-term sustainable growth. Racism, genocide, inequity, sabotage … the list sprawls.

Meanwhile, we continue to look outward, peering at the dark depths between the stars, hoping for a sign that we aren’t alone in the universe. Ultimately, our quest to find life beyond Earth is part of trying to understand life on our planet and where we fit in. As Carl Sagan said:

In the deepest sense, the search for extraterrestrial intelligence is a search for ourselves.

Bottom line: Scientists say the reason we haven’t found intelligent civilizations in the galaxy is that they may not have survived the Great Filter. And they say we may be facing down our own Great Filter.

Source: https://arxiv.org/ftp/arxiv/papers/2210/2210.10582.pdf

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We are a funny bunch! As was said just a couple of paragraphs ago we humans must work together and recognise the big picture. But we do not!

Why do we not do that?

I wish I knew the answer to that conundrum! Nevertheless, I hope you enjoyed the article.

Simply in awe!

It’s both beautiful and yet beyond comprehension.

When we have a clear night there are two occasions for me to gaze upwards and become lost in thought. One is in the evening when the dogs are outside just before going to bed. The other is in the morning because we are usually awake well before sunrise.

We are very lucky in that there is no light pollution locally.

So, in the evening, while I look at the broad expanse of stars, my eyes are drawn to the Big Dipper and to Orion.

In the morning, when we look to the East there is Venus sparkling bright in the night-sky over the hills.

I still vividly remember all those years ago when I was sailing in the Western Mediterranean coming on deck in the middle of the night to find the stars down to the horizon all 360 degrees about me. I am sure it will be one of the last memories of mine just before I die! I hope so!

But I speak of the solar system. Here’s an article that was recently published by EarthSky that goes way beyond the solar system. It is a wonderful essay and almost mystical.

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What is a galaxy?

Posted by Andy Briggs in ASTRONOMY ESSENTIALS, September 25, 2020

We live in a galaxy called the Milky Way. But there is so much more to know about these grand and glorious star islands in space! Click in here, and prepare to have your mind expanded.

This is a giant galaxy cluster known as Abell 2744, aka Pandora’s Cluster, located in the direction of the constellation Sculptor. The cluster is about 4 million light-years across and has the mass of 4 trillion suns. It appears to be the result of a simultaneous pile-up of at least 4 separate, smaller galaxy clusters that took place over a span of 350 million years. Read more about this image at HubbleSite. Image via NASA/ ESA/ J. Lotz/ M. Mountain/ A. Koekemoer/ the Hubble Frontier Fields Team.

A galaxy is a vast island of stars in an ocean of space. Galaxies are typically separated from one another by huge distances measured in millions of light-years. Galaxies are sometimes said to be the building blocks of our universe. Their distribution isn’t random, as one might suppose: galaxies are strung out along unimaginably long filaments across the universe, a cosmic web of star cities.

A galaxy can contain hundreds of billions of stars and be many thousands of light-years across. Our own galaxy, the Milky Way, is around 100,000 light-years in diameter. That’s about 587,900 trillion miles, nearly a million trillion kilometers.

Galaxies are of widely varying sizes, too.

There are an estimated two trillion galaxies in the universe.

Illustration showing snapshots from a simulation by astrophysicist Volker Springel of the Max Planck Institute in Germany. It represents the growth of cosmic structure (galaxies and voids) when the universe was 0.9 billion, 3.2 billion and 13.7 billion years old (now). Image via Volker Springel / MPE/ Kavli Foundation.

Galaxies group together in clusters. Our own galaxy is part of what is called the Local Group, for example: a cluster comprising 55 galaxies that we know of so far.

In turn, galaxy clusters themselves group into superclusters. Our Local Group is part of the Virgo Supercluster.

The “glue” that binds stars into galaxies, galaxies into clusters, clusters into superclusters and superclusters into filaments is – of course – gravity, the universe’s construction worker, which sculpts all the structures we see in the cosmos.

Distances from the Local Group for selected groups and clusters within the Local Supercluster, which is called the Virgo Supercluster.

There are several basic types of galaxy, each containing sub-types. Galaxies were first systematically classified, based on their visual appearance, by the famous astronomer Edwin P. Hubble in the late 1920s and 30s, during years of painstaking observations. Hubble’s Classification of Galaxies, as it is known, is still very much in use today, although, since Hubble’s time, like any good classification system it has been updated and amended in the light of new observations.

Before Hubble’s study of galaxies, it was believed that our galaxy was the only one in the universe. Astronomers thought that the smudges of light they saw in their telescopes were in fact nebulae within our own galaxy and not, as Hubble discovered, galaxies in their own right. It was Hubble who demonstrated, by measuring their velocities, that they lie at great distances from us, millions of light-years beyond the Milky Way, distances so huge that they appear tiny in all but the largest telescopes. Moreover, he demonstrated that, wherever he looked, galaxies are receding from us in all directions, and the further away they are, the faster they are receding. Hubble had discovered that the universe is expanding.

A diagrammatic representation of Edwin Hubble’s “tuning fork diagram.” In the late 1920s and 30s, Hubble conducted the laborious observations needed to begin to classify galaxies. His original classification scheme was published in 1936 in a book called “The Realm of the Nebulae.” His original scheme is – like all scientific work – continually being modified. But his idea of a “tuning fork diagram” has continued to be useful. Image via Las Cumbres Observatory.

The most common type of galaxy is the one most people are familiar with: the spiral galaxy. The Milky Way is of this family. Spiral galaxies have majestic, sweeping arms, thousands of light years long, made up of millions upon millions of stars. Our solar system is situated about 2/3 of the way out from the galactic center towards the periphery of the galaxy, embedded in one of these spiral arms.

Spiral galaxies are also characterised by having a bright center, made up of a dense concentration of stars, so tightly packed that from a distance the galaxy’s center looks like a solid ball. This ball of stars is known as the galactic bulge. At the center of the Milky Way – within the galactic bulge – the density of stars has been calculated at 1 million per 34 cubic light-years, for example.

Meanwhile, in the vicinity of our sun, the stellar density has been estimated as 0.004 stars per cubic light-year. Big difference!

A stunning view of the center of our Milky Way galaxy as seen by the Murchison Widefield Array (MWA) telescope in Australia in 2019. Image via Natasha Hurley-Walker (ICRAR/ Curtin)/ GLEAM Team/ Phys.org.

The Milky Way is, in fact, in one of Hubble’s spiral galaxy sub-types: it’s a barred spiral, which means it has a bar of stars protruding out from either side of the center. The ends of the bar form the anchors of the spiral arms, the place from where they sweep out in their graceful and enormous arcs. This is a fairly recent discovery: how the bar forms in a galaxy is not yet understood.

Also established recently is the fact that the disk of the Milky Way is not, as most diagrams depict, flat: it is warped, like a long-playing vinyl record left too long in the sun. Exactly why is not known, but it is thought to be the result of a gravitational encounter with another galaxy early in the Milky Way’s history.

Artist’s illustration of our warped Milky Way. Image via Ogle/ Warsaw University/ BBC.

Elliptical galaxies are the universe’s largest galaxies. They are huge and football-shaped.

They come to be because – although most galaxies are flying apart from each other – those astronomically close to each other will be mutually gravitationally attracted. Caught in an inexorable gravitational dance, eventually they merge, passing through each other over millions of years, eventually forming a single, amorphous elliptical galaxy. Such mergers may result in the birth of new generations of stars as gravity’s shock-wave compresses huge clouds of interstellar gas and dust.

The Milky Way is caught in such a gravitational embrace with M31, aka the Andromeda galaxy, which is 2 1/2 million light-years distant. Both galaxies are moving toward each other because of gravitational attraction: they will merge in about 6 billion years from now. However, both galaxies are surrounded by huge halos of gas which may extend for millions of light-years, and it was recently discovered that the halos of the Milky Way and M31 have started to touch.

The two galaxies have had their first kiss.

Galaxy mergers are not uncommon: the universe is filled with examples of galaxies in various stages of merging together, their structures disrupted and distorted by gravity, forming bizarre and beautiful shapes.

Galaxies may take billions of years to fully merge into a single galaxy. As astronomers look outward in space, they can see only “snapshots” of this long merger process. Located 300 million light-years away in the constellation Coma Berenices, these 2 colliding galaxies have been nicknamed The Mice because of the long tails of stars and gas emanating from each galaxy. Otherwise known as NGC 4676, the pair will eventually merge into a single giant galaxy. Image via Wikimedia Commons.

At the lower end of the galactic size scale, there are the so-called dwarf galaxies, consisting of a few hundred to up to several billion stars. Their origin is not clear. Usually they have no clearly defined structure. Astronomers believe they were born in the same way as larger galaxies like the Milky Way, but for whatever reason they stopped growing. Ensnared by the gravity of a larger galaxy, they orbit its periphery. The Milky Way has around 20 dwarf galaxies orbiting it that we know of, although some models predict there should be many more.

The two most famous dwarf galaxies for us earthlings are, of course, the Small and Large Magellanic Clouds, visible to the unaided eye in Earth’s Southern Hemisphere sky.

Eventually, these and other dwarf galaxies will be ripped apart by the titanic maw of the Milky Way’s gravity, leaving behind a barely noticeable stream of stars across the sky, slowly dissipating over eons.

Lynton Brown captured this beautiful image of the Milky Way over Taylor’s Lake near Horsham, Australia, on April 22, 2019. The 2 objects on the right are the Magellanic Clouds. Thank you, Lynton!

It is believed that all galaxies rotate: the Milky Way takes 226 million years to spin around once, for example. Since its birth, therefore, the Earth has travelled 20 times around the galaxy.

At the center of most galaxies lurks a supermassive black hole, of millions or even billions of solar masses. The record holder, TON 618, has a mass 66 billion times that of our sun.

The origin and evolution of supermassive black holes are not well understood. A few years ago, astronomers uncovered a surprising fact: in spiral galaxies, the mass of the supermassive black hole has a direct linear relationship with the mass of the galactic bulge. The more mass the black hole has, the more stars there are in the bulge. No one knows exactly what the significance of this relationship is, but its existence seems to indicate that the growth of a galaxy’s stellar population and that of its supermassive black hole are inextricably linked.

This discovery comes at a time when astronomers are beginning to realize that a supermassive black hole may control the fate of its host galaxy: the copious amounts of electromagnetic radiation emitted from the maelstrom of material orbiting the central black hole, known as the accretion disk, may push away and dissipate the clouds of interstellar hydrogen from which new stars form. This acts as a throttle on the galaxy’s ability to give birth to new stars. Ultimately, the emergence of life itself may be tied to the activity of supermassive black holes. This is an area of much ongoing research.

While astronomers still know very little about exactly how galaxies formed in the first place – we see them in their nascent forms existing only a few hundred million years after the Big Bang – the study of galaxies is an endless voyage of discovery.

Less than a hundred years after it was realized that other galaxies beside our own exist, we have learned so much about these grand, majestic star cities. And there is still much to learn.

Bottom line: What is a galaxy? Learn about these starry islands in space.

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There are an estimated two trillion galaxies out there. It is beyond comprehension. Well it is to this mind sitting in front of his Mac in a rural part of Oregon. Two trillion! I can’t even get my mind around the fact that our local galaxy, our Milky Way, is 100,000 light years across. Although some would say that it is even larger; about 150,000 light years across. And what is a light year?

Here’s NASA to answer that:

A light-year is a unit of distance. It is the distance that light can travel in one year. Light moves at a velocity of about 300,000 kilometers (km) each second. So in one year, it can travel about 10 trillion km. More precisely, one light-year is equal to 9,500,000,000,000 kilometers.

Why would you want such a big unit of distance? Well, on Earth, a kilometer may be just fine. It is a few hundred kilometers from New York City to Washington, DC; it is a few thousand kilometers from California to Maine. In the universe, the kilometer is just too small to be useful. For example, the distance to the next nearest big galaxy, the Andromeda Galaxy, is 21 quintillion km. That’s 21,000,000,000,000,000,000 km. This is a number so large that it becomes hard to write and hard to interpret. So astronomers use other units of distance.

In our solar system, we tend to describe distances in terms of the Astronomical Unit (AU). The AU is defined as the average distance between the Earth and the Sun. It is approximately 150 million km (93 million miles). Mercury can be said to be about 1/3 of an AU from the Sun and Pluto averages about 40 AU from the Sun. The AU, however, is not big enough of a unit when we start talking about distances to objects outside our solar system.

For distances to other parts of the Milky Way Galaxy (or even further), astronomers use units of the light-year or the parsec . The light-year we have already defined. The parsec is equal to 3.3 light-years. Using the light-year, we can say that :

The Crab supernova remnant is about 4,000 light-years away.
The Milky Way Galaxy is about 150,000 light-years across.
The Andromeda Galaxy is 2.3 million light-years away.

So here we are. In a remote part of our galaxy, the Milky Way, far, far from everywhere, on a pale blue dot. As Carl Sagan put it in his talk from The Age of Exploration given in 1994:

On it, everyone you ever heard of… The aggregate of all our joys and sufferings, thousands of confident religions, ideologies and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilizations, every king and peasant, every young couple in love, every hopeful child, every mother and father, every inventor and explorer, every teacher of morals, every corrupt politician, every superstar, every supreme leader, every saint and sinner in the history of our species, lived there on a mote of dust, suspended in a sunbeam. …
Think of the rivers of blood spilled by all those generals and emperors so that in glory and triumph they could become the momentary masters of a fraction of a dot.

Carl Sagan, Cornell lecture in 1994

It all seems impossible for us mortals to understand.

But it won’t stop me from peering up into the night sky and wondering about the universe with total awe.

And thank goodness for dogs!

Think you know our Solar System – Think again!

An incredible discovery about the motion of the sun, and the planets.

Serendipity

I have turned on my computer. It’s 15:30 on Sunday. My creative juices re Monday’s blog post are not flowing. Why? Because, together with a young helper who comes over most Sunday mornings, this morning we have shifted 100 bales of hay from outside the garage, taken them down to the hay-loft and stacked them floor to ceiling: all two and a half tons of them! To use an old English colloquial expression: I am fair knackered!

Then I am rescued!

Top of my email inbox is an email from Dan Gomez that is an item sent to him from his brother Chris. It’s a truly incredible discovery. One that requires us all to tear up what we understand about the Solar System and start again.

Here is the essay in question. It has been recently published on the Spirit, Science and Metaphysics website.

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Our Model Of The Solar System Has Been Wrong This Entire Time!

Written by Amateo Ra

If you walk into any classroom today, and likely ever since you were a kid yourself , there is one model being taught regarding the structure of our Solar System. It’s the model that looks like this:

It’s the traditional orbiting model of the Solar System, or the Heliocentric Model, where our planets rotate around the sun.

While this isn’t entirely wrong, it’s omitting one very important fact. The sun isn’t stationary. The sun is actually travelling at extremely fast speeds, upward of 828,000 km/hr, or 514,000 miles an hour.
Our whole Solar System is orbiting the Milky Way Galaxy. In fact it takes 220-Million Years for the Sun to orbit our Galaxy.

Knowing this to be true, our visual model of the Solar System needs to change, and has been inaccurate this whole time. In fact, our planets are barreling through space with the sun, and literally creating a giant Cosmic DNA Helix, and a vortex similar to our Milky Way Galaxy.

Like this but in space, creating a never ending Sine Wave.

This entails that our Sun & the Planets of our Solar System are never in the same place. When we make one rotation around the sun, we have already traveled millions of miles through space, meaning these Cosmic Cycles are far grander than we might have previously imagined.

Here are two video examples of the Helical Model of our Solar System:

This is one by Physicist Nassim Haramein, which clarifies the difference:

Here is a beautiful digital representation of how our solar system is actually a vortex.

Thanks & Spread the Word! Let’s get this changed in Classrooms all around the World.

About the author: Amateo Ra is the co-founder of Creator Course, an Online School for Conscious Living which is currently being built. For the last 4-years, he has been training with Global leaders in Spirituality, Channeling & Conscious Business.

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Don’t know about you but reading this for the first time and watching the two videos really invigorated me. What an amazing universe it is out there!

Clouds above, and even farther away.

The second, and last, episode of the BBC Clouds Lab programme offers an intriguing message.

On Monday, I published a post under the title of The clouds above us. The second episode demonstrated that even in atmospheric conditions of near vacuum, intense cold and very low humidity, conditions that would kill a human in seconds, there was microscopic bacteriological material to be found.

Exploring the troposphere

The troposphere is a turbulent layer of air that begins at the Earth’s surface and ranges from 23,000-65,000 feet above sea level, depending on the latitude, season and the time of day. Its name originates from the Greek word tropos, meaning change. It’s now known that bacteria actually exists in clouds and scientists believe that it plays a significant part in the creation of rain but little is known about life higher up. Microbiologist Dr Chris Van Tulleken has discovered that living bacteria can exist well above 10,000ft in a hostile environment with low pressure, increased UV radiation, freezing temperatures, high winds and no oxygen or water.

There is an interesting set of clips to be watched on that BBC Cloud Lab website.

What I took away from watching the programme was that the minimum conditions necessary for living bacteria were far more harsh than one might expect. In other words, finding living bacteria in other solar systems might not be such a science-fiction idea.

With that in mind, I’m republishing an essay that Patrice Ayme wrote in 2013. I’m grateful for his permission to so do.

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40 Billion Earths? Yes & No.

Up to twenty years ago, a reasonable opinion among scientists was that there might be just one solar system. Ours. Scientists like to project gravitas; having little green men all over didn’t look serious.

However, studying delicately the lights of stars, how they vary, how they doppler-shift, more than 1,000 planets have been found. Solar systems seem ubiquitous. Astronomers reported in 2013 that there could be as many as 40 billion habitable Earth-size planets in the galaxy. However, consider this:

Centaurus A: Lobes Of Tremendous Black Hole Explosion Fully Visible.

Yes, that’s the center of a galaxy, and it has experienced a galactic size explosion from its central black hole.

One out of every five sun-like stars in our galaxy has a planet the size of Earth circling it in the Goldilocks zone, it seems — not too hot, not too cold — with surface temperatures compatible with liquid water. Yet, we have a monster black hole at the center of our giant galaxy, just like the one exploding above.

The Milky Way’s black hole is called Sagittarius A*. It exploded last two million years ago. Early Homo Erectus, down south, saw it. The furious lobes of the explosion are still spreading out, hundreds of thousands of light years away.

We are talking here about explosions potentially stronger than the strongest supernova by many orders of magnitude (depending upon the size of what’s falling into Sagittarius. By the way, a cloud is just heading that way).

Such galactic drama has a potential impact on the presence of advanced life. The richer the galaxy gets in various feature the situation looks, the harder it looks to compute the probability of advanced life.

The profusion of habitable planets is all the more remarkable, as the primitive methods used so far require the planet to pass between us and its star.

(The research, started on the ground in Europe, expanded with dedicated satellites, the French Corot and NASA’s Kepler spacecraft.). Sun-like stars are “yellow dwarves”. They live ten billion years.

From that, confusing “habitable” and “inhabitated”, the New York Times deduced: “The known odds of something — or someone — living far, far away from Earth improved beyond astronomers’ boldest dreams on Monday. “

However, it’s not that simple.

Primitive bacterial life is probably frequent. However advanced life (animals) is probably very rare, as many are the potential catastrophes. And one needs billions of years to go from primitive life to animals.

After life forms making oxygen on Earth appeared, the atmosphere went from reducing (full of strong greenhouse methane) to oxidizing (full of oxygen). As methane mostly disappeared, so did the greenhouse. Earth froze, all the way down to the equator:

Yet volcanoes kept on belching CO2 through the ice. That CO2 built up above the ice, caused a strong greenhouse, and the ice melted. Life had survived. Mighty volcanism has saved the Earth, just in time.

That “snowball Earth” catastrophe repeated a few times before the Earth oxygen based system became stable. Catastrophe had been engaged, several times, but the disappearance of oxygen creating life forms had been avoided, just barely.

Many are the other catastrophes we have become aware of, that could wipe out advanced life: proximal supernovas or gamma ray explosions.

Cataclysmic eruption of the central galactic black hole happen frequently. The lobes from the last one are still visible, perpendicularly high off the galactic plane. The radiation is still making the Magellanic Stream simmer, 200,000 light years away. Such explosions have got to have sterilized a good part of the galaxy.

In 2014 when part of the huge gas cloud known as G2 falls into Sagittarius A*, we will learn better how inhospitable the central galaxy is for advanced life.

Many of the star systems revealed out there have surprising feature: heavy planets (“super Jupiters“) grazing their own stars. It’s unlikely those giants were formed where they are. They probably swept their entire systems, destroying all the rocky planets in their giant way. We don’t understand these cataclysmic dynamics, but they seem frequent.

Solar energy received on Earth fluctuated and changed a lot, maybe from one (long ago) to four (now). But, as it turned out just so that Earthly life could survive. Also the inner nuclear reactor with its convective magma and tectonic plates was able to keep the carbon dioxide up in the air, just so.

The Goldilocks zones astronomers presently consider seem to be all too large to allow life to evolve over billions of years. They have to be much narrower and not just with red dwarves (the most frequent and long living stars).

One of our Goldilocks, Mars, started well, but lost its CO2 and became too cold. The other Goldilocks, Venus, suffered the opposite major technical malfunction: a runaway CO2 greenhouse.

Mars’ axis of rotation tilts on the solar system’s plane enormously: by 60 degrees, over millions of years. So Mars experiences considerable climatic variations over the eons, as it goes through slow super winters and super summers (it’s imaginable that, as the poles melt, Mars is much more habitable during super summers; thus life underground, hibernating is also imaginable there).

Earth’s Moon prevents this sort of crazy hyper seasons. While, differently from Venus, Earth rotates at reasonable clip, homogenizing the temperatures. Venus takes 243 days to rotate.

It is startling that, of the four inner and only rocky planets, just one, Earth has a rotation compatible with the long term evolution of advanced life.

Earth has also two striking characteristics: it has a very large moon that store much of the angular momentum of the Earth-Moon system. Without Moon, the Earth would rotate on itself once every 8 hours (after 5 billion years of braking by Solar tides).

The Moon used to hover at least ten times closer than now, when earth’s days were at most 6 hours long.

The tidal force is the difference between gravitational attraction in two closely separated places, so it’s the differential of said attraction (which is proportional to 1/dd; d being the distance). Hence the tidal force is inversely proportional to the cube of the distance.

Thus on early Earth tides a kilometer high were common, washing back and forth every three hours. a hyper super tsunami every three hours, going deep inside the continents. Not exactly conditions you expect all over the universe.

Hence biological material fabricated on the continental margins in shallow pools would get mixed with the oceans readily. That would guarantee accelerated launch of life (and indeed we know life started on Earth very fast).

The theory of formation of the Moon is wobbly (recent detailed computations of the simplest impact theory do not work). All we know for sure, thanks to the Moon rocks from Apollo, is that the Moon is made of Earth mantle materials.

Somehow the two planets split in two. (Fission. Get it? It maybe a hint.)

Another thing we know for sure is that Earth has, at its core, a giant nuclear fission reactor, keeping Earth’s core hotter than the surface of the sun. An unimaginable liquid ocean of liquid iron deep down inside below our feet undergoes iron weather. Hell itself, the old fashion way, pales in comparison.

Could the Moon and the giant nuclear reactor have the same origin? This is my provocative question of the day. The Moon, our life giver, could well have formed from giant nuclear explosions, of another of our life givers, what became the nuke at the core. I can already hear herds of ecologists yelp in the distance. I present the facts, you pseudo-ecologists don’t decide upon them. It’s clear that nuclear fission is not in Drake equation: if nothing else, it’s too politically incorrect.

All the preceding makes this clear:

Many are the inhabitable planets, yet few will be inhabitated by serious denizens.

This means that the cosmos is all for our taking. The only question is how to get there. The closest stars in the Proxima, Beta and Alpha Centauri system are not attainable, for a human crew, with existing technology.

However, if we mastered clean colossal energy production, of the order of the entire present energy production of humanity, we could get a colony there (only presently imaginable technology would be fusion).

Giordano Bruno, professor, astronomer, and priest suggested that there were many other inhabitated systems around the stars. That insult against Islam meant Christianity was punished the hard way: the Vatican, the famous terrorist organization of god crazies, put a device in Giordano’s mouth that pierced his palate, and having made sure that way that he could not tell the truth, the terrorists then burned him alive. After seven years of torture.

The horror of truth was unbearable to theo-plutocrats.

Now we face something even worse: everywhere out there is very primitive life. It is likely gracing 40 billion worlds. But, if one has to duplicate the succession of miracles and improbabilities that made Earth, to earn advanced life, it may be just here that civilization ever rose to contemplate them.

Congratulations to India for launching yesterday a mission to Mars ostensibly to find out if there is life there (by finding CH4; while life is presently unlikely, Mars has much to teach, including whether it started there). That’s the spirit!

The spirit is to have minds go where even imagination itself did not go before.

If we sit back, and look at the universe we have now, from Dark Matter, to Dark Energy, to Sagittarius, to the nuclear reactor below, to billions of Earths, to a strange Higgs, to Non Aristotelian logic, we see a wealth, an opulence of possibilities inconceivable twenty years ago.

Progress is not just about doing better what was done yesterday. It’s also about previously inconceivable blossoms of entirely new mental universes.

***

Patrice Ayme

ooOOoo

Maybe, we are not alone!

Not of immediate concern!

Milky Way galaxy heading for a collision – in about 4,000,000,000 years!

As with huge numbers of others who come to this blog, the night sky has always been of incredible fascination to me. To reinforce that fact, one of the favourite posts on Learning from Dogs for the last three years has been The night sky above published back on the 27th March, 2011. If you haven’t read it, do pop across and do so as the title is misleading in terms of the post.

Thus it was unavoidable not to pick up on an item recently referred to by Naked Capitalism that had been published by the EarthSky blog. This particular item was called Night sky as Milky Way and Andromeda galaxies merge. It began thus:

As seen on Cosmos … the collision and merger between our Milky Way galaxy and the nearby Andromeda galaxy 4 billion years from now.

The video below illustrates what NASA scientists announced in 2012 – and what the Cosmos TV series featured in 2014 – that the nearby Andromeda galaxy will collide and merge with our Milky Way galaxy 4 billion years from now. The video (from the Hubble Space Telescope news center) is from a series of photo illustrations, showing the predicted merger between our two titan spiral galaxies, as seen in Earth’s sky. Will Earth as a planet survive long enough to see this? A word about that at the end of this post.

The video lost a lot for me by not carrying a commentary. But no problem as one was found that did have a ‘voice-over’. However, the article photographs were stunning. For example:

This series of photo illustrations shows the predicted merger between our Milky Way galaxy and the neighboring Andromeda galaxy. Via NASA; ESA; Z. Levay and R. van der Marel, STScI; T. Hallas, and A. Mellinger

A description of what’s happening in the images above:

First Row, Left: Present day.
First Row, Right: In 2 billion years the disk of the approaching Andromeda galaxy is noticeably larger.
Second Row, Left: In 3.75 billion years Andromeda fills the field of view.
Second Row, Right: In 3.85 billion years the sky is ablaze with new star formation.
Third Row, Left: In 3.9 billion years, star formation continues.
Third Row, Right: In 4 billion years Andromeda is tidally stretched and the Milky Way becomes warped.
Fourth Row, Left: In 5.1 billion years the cores of the Milky Way and Andromeda appear as a pair of bright lobes.
Fourth Row, Right: In 7 billion years the merged galaxies form a huge elliptical galaxy, its bright core dominating the nighttime sky.

The sequence is inspired by dynamical computer modeling of the inevitable future collision between the two galaxies.

Further on in the article one reads:

This illustration shows the collision paths of our Milky Way galaxy and the Andromeda galaxy. The galaxies are moving toward each other under the inexorable pull of gravity between them. Also shown is a smaller galaxy, Triangulum, which may be part of the smashup. Via NASA; ESA; A. Feild and R. van der Marel, STScI.

Will Earth survive long enough to see this merger of galaxies, as depicted in the video above? Earth as a planet might, but life on Earth – probably not. Astronomers say that the luminosity, or intrinsic brightness, of our sun will steadily increase over the next 4 billion years. As the sun’s luminosity increases, the amount of solar radiation reaching the Earth will also increase. It’s possible that – around 4 billion years from now – the increase in the Earth’s surface temperature will cause a runaway greenhouse effect, perhaps similar to that going on now on the planet next door, Venus, whose surface is hot enough to melt lead. No one expects to find life on Venus. Likewise, life on Earth will probably not exist 4 billion years from now. What’s more, our sun is expected to become a red giant star eventually. A probable fate of the Earth is absorption by the sun in about 7.5 billion years, after our sun has entered the red giant phase and expanded to cross Earth’s current orbit.

Anyhow, I mentioned that I found a better video on YouTube than the one included in the original article, and that is now presented.

Rather puts the grunt and grind of daily life into perspective! 😉

Just one in trillions!

The immensity of the universe and what it means for Planet Earth.

Jean and I have been watching the astounding BBC Series Wonders of Life presented by Professor Brian Cox. Here’s the BBC trailer:

and there are more clips from the programmes on the relevant part of the BBC website. There is so much about the series that is breath-taking. So much that reminds one of what a beautiful and fragile planet we live on. Quite rightly, the series received great reviews. Here, for example, is a little of what the UK Daily Telegraph newspaper wrote:

Wonders of Life, BBC Two, review

Sarah Crompton reviews the first episode of Brian Cox’s latest series, Wonders of Life (BBC Two).

By Sarah Crompton

10:00PM GMT 27 Jan 2013

When it comes to presenting styles, Professor Brian Cox is hard to keep still. There isn’t a beach he won’t feel compelled to stroll on, a mountain he won’t climb, or a river he won’t jump into. And what does he carry in that bag?

Once you got beyond these irritating stylistic tropes, however, Wonders of Life (BBC Two) was Cox at his absolute best, using his natural enthusiasm to communicate complicated ideas in very simple ways. He decided, for example, to show us his own DNA by spitting in a test tube – and missed.

“A physicist doing an experiment,” he giggled, with unforced charm. But when he actually succeeded, those little strands of white that you suddenly see brought everything he subsequently said to life.

He was brilliant at explaining his thesis, which was actually about the second law of thermodynamics, so not that much of a doddle to grasp. If I’ve got it right, what Cox thinks is that life itself may have been the inevitable consequence of the laws of physics and can be explained in the same terms as we explain “the falling of the rain and the shining of the stars”.

Sarah rounds off her review, thus:

The programme’s sophisticated use of graphics, and Cox’s patient repetition of his conclusions, all added to the sensation that this is a series that is actually going to tell you something. For the BBC to unveil both this and The Story of Music over a single weekend reveals a pretty impressive commitment to public service broadcasting. Long may it last.

One of the clear messages that comes from the program is the fact that our universe and the formation of life are intimately connected. That the ‘big bang’ some 3.2 billion years ago, the huge interstellar gas clouds, the formation of the carbon atom and the subsequent long-chained molecules, the collapse of those gas clouds to form suns and planets, the start of life, evolution through natural selection to ever more complex life forms, and on and on and on were and are inevitable. The science is clear. There is nothing mystical about it.

Yes, of course, anyone with half-an-ounce of sensitivity will be in awe of it all; the power and beauty of nature and of the natural world.

But here’s the rub.

As another BBC television programme explained, the universe is bigger than beyond imagination. That was from the BBC Horizon broadcast of August, 2012: How Big is the Universe? Here’s the trailer for that programme.

Stay with me a little longer! Just look at the following image.

This image of the Andromeda galaxy, taken in infrared and X-ray, consists of over a trillion stars.

The detailed Spitzer Space Telescope view above features infrared light from dust (red) and old stars (blue) in Andromeda, a massive spiral galaxy a mere 2.5 million light-years away. In fact, with over twice the diameter of our own Milky Way, Andromeda is the largest nearby galaxy. Andromeda’s population of bright young stars define its sweeping spiral arms in visible light images, but here the infrared view clearly follows the lumpy dust lanes heated by the young stars as they wind even closer to the galaxy’s core. Constructed to explore Andromeda’s infrared brightness and stellar populations, the full mosaic image is composed of about 3,000 individual frames. Two smaller companion galaxies, NGC 205 (below) and M32 (above) are also included in the combined fields. The data confirm that Andromeda (aka M31) houses around 1 trillion stars, compared to 4 hundred billion for the Milky Way.

Please stay with me for a few more minutes. Keeping the Andromeda galaxy in mind, now read this:

March 29, 2013

An ‘Infinity of Dwarfs’ –A Visible Universe of 7 Trillion Dwarf Galaxies

ESA astronomers say that for every ten far galaxies observed, a hundred go undetected.

Astronomers estimate that there are between 100 billion and 200 billion galaxies in the known universe. A single galaxy such as the Milky Way contain upwards of 200 billion normal stars. About 75 percent of all stars in the Milky Way are less than half as massive as our Sun. In the universe at large, the majority of galaxies are classified as dwarfs, each with less than a few hundred million stars. The image above is a computer simulation of a colliding dwarf galaxy triggering the formation of the Milky Ways spiral arms.

The largest project ever undertaken to map out the Universe in three dimensions using ESO telescopes has reached the halfway stage. An international team of astronomers has used the VIMOS instrument on the ESO Very Large Telescope to measure the distances to 55,000 galaxies as part of the VIPERS survey (VIMOS Public Extragalactic Redshift Survey). This has already allowed them to create a remarkable three-dimensional view of how galaxies were distributed in space in the younger Universe.This reveals the complex web of the large-scale structure of the Universe in great detail. The light of each galaxy is spread out into its component colours within VIMOS. Follow up analysis then allows astronomers to work out how fast the galaxy appears to move away from us — its redshift. This in turn reveals its distance and, when combined with its position on the sky, its location in the Universe.

Wow!

Millions of galaxies, trillions of suns, inconceivable numbers of planets.

Please pause and let the numbers sink in.

Now back to that Wonders of Life BBC series, during which Professor Brian Cox, said, “that it is inconceivable that there isn’t life elsewhere, that life is not present on countless other planets circling countless other suns …“.

In other words, if mankind is so intent on ‘fouling our nest’ on this most beautiful of planets, so what!

In the bigger scheme of things, it matters not. Find that tough? Then go and hug a dog and enjoy the moment. For tomorrow may never come.

The Goldilocks Planet.

Neither too close nor too far from the Sun.

Towards the end of the lecture that Lord Martin Rees gave at University of Melbourne’s Medical School in 2010, he spoke of the way that Planet Earth has warmed up these last 100 years, warmed up uniquely. Why the word ‘uniquely’? Because, for the first time in the ancient life of our planet, that warming is the result of the activity of a life species living on that planet; mankind. It’s difficult to comprehend how special, how fragile and, therefore, how vulnerable is mankind’s ability to survive on Planet Earth. That’s why a recent item on Martin Lack’s excellent blogsite Lack of Environment is published on Learning from Dogs with Martin’s kind permission. But first let me quote a little from WikiPedia about the ‘goldilocks principle’,

In astronomy and astrobiology, the habitable zone is the region around a star where a planet with sufficient atmospheric pressure can maintain liquid water on its surface.^[1]¹ Since liquid water is essential for all known forms of life, planets in this zone are considered the most promising sites to host extraterrestrial life. The terms “ecosphere” and “Liquid Water Belt” were introduced by Hubertus Strughold and Harlow Shapley respectively in 1953.^[2] Contemporary alternatives include “HZ”, “life zone”, and “Goldilocks Zone.”^[3]

“Habitable zone” is sometimes used more generally to denote various regions that are considered favorable to life in some way. One prominent example is the Galactic habitable zone’ (the distance from the galactic centre). Such concepts areinferred from the empirical study of conditions favorable for life on Earth. If different kinds of habitable zones are considered, their intersection is the region considered most likely to contain life.

The location of planets and natural satellites (moons) within its parent’s star’s habitable zone (and a near circular orbit) is but one of many criteria for planetary habitability and it is theoretically possible for habitable planets to exist outside the habitable zone. The term “Goldilocks planet” is used for any planet that is located within the CHZ^[4]^[5] although when used in the context of planetary habitability the term implies terrestrial planets with conditions roughly comparable to those of the Earth(i.e. an Earth analog). The name originates from the story of Goldilocks and the Three Bears, in which a little girl chooses from sets of three items, ignoring the ones that are too extreme (large or small, hot or cold, etc.), and settling on the one in the middle, which is “just right”. Likewise, a planet following this Goldilocks Principle is one that is neither too close nor too far from a star to rule out liquid water on its surface. While only about a dozen planets have been confirmed in the habitable zone, the Kepler spacecraft has identified a further 54 candidates and current estimates indicate that there are “at least 500 million” such planets in the Milky Way.^[6]

So now to Martin Lack’s post.

Goodbye Goldilocks Planet?

Is it time to say goodbye to the Goldilocks Planet?

I hope not, because the next-nearest one yet discovered is 600 light years away! However, if we are indeed now passing a tipping point (i.e. as the widespread rapid thawing of Siberian permafrost suggests) both mitigation and adaptation will be almost impossible. Therefore, if we cannot reverse the damage already done (i.e. how can we make permafrost re-freeze or reverse the retreat of mountain glaciers?), we may have to accept that temperatures will eventually rise to a level at which the Antarctic first became glaciated 35 million years ago; and that sea levels will now rise continuously for several centuries – making any permanent settlement anywhere near the coast impossible (seeJames Hansen in Storms of my Grandchildren).

If your response to all this is to accuse me of being alarmist, all I can say is that I am afraid denial is definitely not a good evolutionary survival mechanism. Furthermore, as American high school science teacher – and now climate change activist – Greg Craven has said,“Unfortunately, the experiment is already running; and we are all in the test-tube!” I believe we must therefore hope that humanity will not repeat the folly of the former inhabitants of Easter Island; who chopped down all their trees for firewood and allowed all the decent soil to be washed away so they could not grow anything.

I think it is fair to say that 2011 was a difficult year for humanity and the planet; and 2012 could be worse. We now seem to be facing both a financial and an environmental crisis: Even at the tender age of 46, I can appreciate that the prospect of 6 years of austerity measures (here in the UK) is completely without precedent; worse even than the great depression of the 1920s. In the UK, public sector workers have been demanding a better pension! What about a better economic system, or even a better planet? If necessary, please forgive my impertinence but, how can people demand justice for themselves whilst ignoring all the injustices we are inflicting on those least able to adapt; and/or bequeathing to our descendants?

This is almost as pessimistic as my recent answer on ClimateSight to the question “Why are people who want to reduce – and possibly eliminate pollution – and create a safer world, considered obstructionist naysayers?“, which is… “If everyone lived as we do in ‘the West’, the planet’s ecological carrying capacity would only be about 3 billion [Paul and Anne Ehrlich (1996)]. Therefore we cannot solve poverty without allowing a lot of people to die or by wealthy people agreeing to moderate their over-consumption of the Earth’s resources. Sorry to be so blunt but, this is the simple answer to the question.” …Despite what detractors say this is not misanthropic eco-Socialism, it is reality. There is not enough decent farmland and/or resources of every kind for 7 billion people or more to live like we currently do in ‘the West’. If we are not going to deny the legitimate aspirations of poorer peoples to attain a better standard of living, we will have to moderate our over-consumption and/or pollution of the Earth’s resources. We cannot have it both ways.

Conclusion
If we continue to burn all the Earth’s fossil fuels – just because they are there and because we can – we will most certainly have to say good bye to our Goldilocks Planet. However, now that we know that what we are doing is causing the problem, would it not be a good idea to stop doing it? You know: When in a hole, stop digging, etc… As the Good Book says, “As a dog returns to its vomit, so a fool repeats his folly” (Proverbs 26:11).

Suggested New Year’s Resolution:
If we want things to change, I believe we must acknowledge that Clive Hamilton is right: climate change is a failure of modern politics – representative democracy is not working! Therefore, we must all take a much more active role in the process of government – this is called participatory democracy – and we must start by demanding that our politicians dismantle (or at least stop being misled by) the fossil fuel lobby who do not want their business as usual programme interrupted.

Having said all that, I would still like to sincerely wish you all the best for 2012 (although I hope the Mayan Calendar is wrong).

All in the meaning, conclusion

Life is without meaning. You bring the meaning to it.

The meaning of life is whatever you ascribe it to be.

Being alive is the meaning.

It would be so easy to stay with this theme for a very long time, perhaps to the end of one’s mortal days.

Anyway, my topic has taken sufficient shape for me to conclude with this article and then leave these ideas with you, or just out there in the universe. The ‘shape’ being that whether the facts about the way we treat Planet Earth depress you, or whether taking a mystic, spiritual view is more your scene, it’s up to you. Let’s recap.

The first article was to show that there are very strong and valid reasons to take an incredibly dim view of where it’s all heading. In fact, those that stay with Learning from Dogs over the weeks, you hardy lot!, will know that the premise that we, as in mankind, are well and truly in the midst of a massive transition, unlike anything ever experienced before, is an idea that crops up here every so often. This piece on the 22nd is just an example, and there are many more articles resonating around this theme on the Blog.

Then the second article was to show that a simple change of perspective can make all the difference to how we see the world. (Oh, and such a big thank-you to Sue Dreamwalker for that beautiful poem from her.)

OK, to the point of this article!

The BBC have been showing the most beautiful episodes in recent weeks from a massive production hosted by Professor Brian Cox- The Wonders of the Universe. Here’s the BBC trailer.

Did you pick up on that key sentence? “Ultimately, we are part of the universe.”

Here’s a recent piece from the British Guardian newspaper, I think written by Brian Cox, the presenter of the series.

The universe is amazing. You are amazing. I am amazing. For we are all one. Everything we are, everything that’s ever been and everything that will ever be was all forged in the same moment of creation 13.7bn years ago from an unimaginably hot and dense volume of matter less than the size of an atom. And that is amazing. [Understatement! Ed.] What happened before then in the Planck epoch is a matter of conjecture; we lack a theory of quantum gravity, though some believe the universe was formed from a collision of two pieces of space and time floating forever in an infinite space, but I feel I’m losing you at this point, which isn’t so amazing.

Read it in full here, but it concludes, almost poetically, as,

Time feels human, but we are only part of Cosmic Time and we can only ever measure its passing. As I stand in front of the great glacier that towers over Lake Argentino, time seems to almost stand still, yet as I explain the effects of entropy in the Namibian desert as sandcastles crumble around me, you can see that the transition from order to chaos can happen almost in the blink of an eye. One day, perhaps in 6bn years, our universe will stop expanding, the sun will cool and die, as all stars must, and everything will collapse in on itself, back into a black hole singularity. I leave you with this last thought: that we, too, will only really die when the universe dies, for everything within it is intrinsically the same.

Brian Cox takes an almost mystical perspective of the size of the universe and the almost unimaginable number of stars and planets it contains.

So, how many stars are out there? From here, I quote,

It’s a great big Universe out there, with a huge numbers of stars. But how many stars are there, exactly? How many stars are there in the Universe? Of course it’s a difficult question to answer, because the Universe is a vast place and our telescopes can’t reach every corner to count the number of stars. But we can make some rough estimates. Almost all the stars in the Universe are collected together into galaxies. They can be small dwarf galaxies, with just 10 million or so stars, or they can be monstrous irregular galaxies with 10 trillion stars or more. Our own Milky Way galaxy seems to contain about 200 billion stars; and we’re actually about average number of stars.

So an average galaxy contains between 10¹¹ and 10¹² stars. In other words, galaxies, on average have between 100 billion and 1 trillion numbers of stars.

Now, how many galaxies are there? Astronomers estimate that there are approximately 100 billion to 1 trillion galaxies in the Universe. So if you multiply those two numbers together, you get between 10²² and 10²⁴ stars in the Universe. How many stars? There are between 10 sextillion and 1 septillion stars in the Universe. That’s a large number of stars.

Even if one writes down in longhand the number, 10²² , as in 10,000,000,000,000,000,000,000 it still has no real meaning whatsover. That, of course, does not even get close to estimating how many planets there are out there.

Let’s say, just as a muse, that each sun only had a single planet. Let us also continue this musing and say that only one in a billion planets had life on it. In other words, if we divide 10²² by a billion, we still get the eye-watering result of there being 10¹³ or, longhand, 10,000,000,000,000 planets with life forms. That’s 10 trillion, by the way!

OK, cut it down some more, and then some more, and even more.

But whichever way you cut it, the conclusion is inescapable, the universe must be teeming with life and much of that life intelligent and wise.

So let me leave you with this thought about the meaning of it all. It’s this.

It is said that the world reflects back what we think about most. As I hope to have shown, we can think our way into extinction, or we can think our way to more mystic and spiritual outcomes. The meaning of life is whatever you ascribe it to be.

In the end, if we screw up this planet as place for mankind to prosper and grow, it’s no big deal. There will be many other humankinds out there in the universe who have taken a different route.

Sleep well tonight!

Cosmic Modesty Required

THE UNIVERSE TEACHES AWE AND HUMILITY

This is a guest post from an old friend of Learning from Dogs, Patrice Ayme. Patrice writes his own Blog here and this article is published with gratitude and with awe! If you can, because the article more than deserves this, find somewhere quiet for half-an-hour to read this – it may well change the way you think about everything.

Theme: Is there extraterrestrial life? Extraterrestrial intelligence? A related question: how big is the universe? On all these subjects considerable and very surprising progress is in the making. I describe some of the new ideas and facts in plain language, from Plate Tectonics to Cosmic Inflation.

Facing the enormity of it all, honest minds will find honor and pleasure in telling the truth, and nothing but the truth (carefully distinguishing it from hope we can believe in). Some physicists, searching for the limelight, have presented some science fiction, or some science fantasy, or let’s say scientific working hypotheses, philosophically grounded, as real, established science. This is misleading and dangerous: science is truth, and that is why the public supports it. Let’s keep it that way.

Sometimes all that science does, but that is fundamental, is to find new uncertainties we did not previously suspect. A basic humility that needs to be taught to people and politicians is that knowledge is not just about learning what we know, but also about learning that there are new dimensions to what we don’t know.

One certainty: our Earth is rare and fragile. Earth was a primordial deity of the Greeks, Gaia, viewed as female, nourishing humankind. Gaia is an on-going miracle, of self regulation, with extremely complicated biology and physics entangled. The more we observe the cosmos, the more we see that’s hell out there. Gaia is a rare deity, Pluto is the rule. Here are some inklings.

***

ALIEN SOLAR SYSTEMS EVERYWHERE:

Many planets have been discovered around many stars. Solar systems (= several planets orbiting the same star) have also been discovered. In one of these systems three planets around a dwarf red star are all in the inhabitable zone (= neither too cold nor too hot, so that liquid water exists on a planet there). One of them is smack in the middle of the balmy zone. It seems clear that most stars will be found to have planets (we are above 30%, and our present detection methods are very crude).

Still there does not seem to be many civilizations out there. As Enrico Fermi put it:”Where is everybody?”

Far enough from the dangerous galactic center, with its zooming stars, high radiation, and gigantic black hole, but not far enough to miss the full wealth of the periodic table, with its many elements, there is a narrow band all around the galaxy, the inhabitable zone, with at least 50 billion suns (within the trillion suns of the Milky Way).

Everything indicates that there are billions of colonizable planets in the inhabitable zone of our galaxy: colonialism has a great future (once we find how to get there). Life could have started on many of these planets. But on most of these, it was quickly annihilated: hellish, incandescent “super-earths” (= rocky planet with masses up to 10 times Earth) ready to fall into their star, abound.

***

INGREDIENTS FOR LIFE: MAGNETOSPHERE, TECTONICS, MOON…

The obvious candidate for the start of life is next door. It is Mars (Venus may have qualified too, the early Sun being 25% weaker; but Venus has long turned into hell, destroying all biological remnants). Everything indicates that life started on Mars. It would be very surprising that it did not.

Probably even OUR life started there. Impacts of asteroids and comets would have thrown living material from Mars to Earth. Mars meteorites have been found in Antarctica, lying on the ice. It has been observed that the temperatures within a Mars meteorite could stay very low: no more than around 40 Celsius, during the entire Mars-Earth transfer.

The Earth stayed too hot for life much longer than Mars, due to its much greater thermal inertia, large, intense radioactive core, greater number of impacts, and having thoroughly melted after the giant impact which created our life fostering Moon.

But then, after an auspicious start, Mars lost most of most of its atmosphere (probably within a billion years or so). Why? Mars is a bit small, its gravitational attraction is weaker than Earth (it’s only 40%). But, mostly, Mars has not enough a magnetic field. During Coronal Mass Ejections, CMEs, the Sun can throw out billions of tons of material at speeds up to and above 3200 kilometers per seconds. It’s mostly electrons and protons, but helium, oxygen and even iron can be in the mix.

The worst CME known happened during the Nineteenth Century, before the rise of the electromagnetic civilization we presently enjoy. Should one such ejection reoccur now, the electromagnetic aspect of our civilization would be wiped out.It goes without saying that we are totally unprepared, and would be very surprised. Among other things, all transformers would blow up, and they take months to rebuild. we would be left with old books in paper, the old fashion way. A CME can rush to Earth in just one day. (Fortunately the Sun seems to be quieting down presently, a bit as it did during the Little Ice Age.)

When a CME strikes a planet, the upper atmosphere is hit by a giant shotgun blast. Except a shotgun blast goes around 300 meters per second, 10,000 times slower than a CME. So, per unit of mass, the kinetic energy of a powerful CME is at least ten billion times more powerful than a shotgun blast. Since the liberation speed is going to be around ten kilometers per second, on an average life supporting planet, to be hit by projectiles going at 3,000 kilometers per second is going to knock all too much of the upper air atoms into space. That’s how Mars lost most of its atmosphere. And thus its ocean and much of its greenhouse. So now Mars is desperately airless, dry, and cold.

PA image — A cluster of new stars forming in the Serpens South cloud

(More on the Serpens constellation here. Ed.)

***

Both Mars and Venus are at the limit of the inhabitable zone. But Venus does not have a magnetic field worth this name. Thus Venus lost a lot of its hydrogen (hence water; the rest is tied up in sulfuric acid, H2SO4).

It is known that the Earth’s strong magnetic field originates from the motion of huge masses of liquid metal within.

So a solar wind shield, a magnetosphere, is tied to the plate tectonic of a very dynamical planet with a powerful nuclear reactor deep inside. Whereas Venus and Mars are tectonically inert, at least, most of the time; maybe they wake up every half a billion years or so, for a big eruption. If Mars and Venus had been very tectonically active planets, may be they would be teeming with life (but that depends upon the distribution of heavy radioactive nuclei in a gathering solar system, an unknown subject, obviously non trivial, since Earth got them, and not the other two).

In any case the Earth’s magnetic shield protects life from the worst abuse of the Sun, as it deflects most of the CMEs out and around (they sneak back meekly as Aurora Borealis).

Another factor in the stable environment Earth provides for life is the Moon. The Earth-Moon system divides its angular momentum, between each other and the orbital motion of the Moon. This prevents the Earth to lay its rotation axis on its side: such a wobbling could not be compensated by the rest of the system. So it does not happen.

Mars, though, not being so impaired, wobbles between 15 and 35 degrees (causing weird, pronounced super-seasonal variations).

In any case, everything indicates that extremely primitive life appears quickly. But complex life needs time, lots of time, to evolve. Animal life and intelligence needs even more time. However, what strikes me in the new solar systems discovered so far, is how alien and unstable they are (this is partly a bias of the present detection methods).

Many of these systems have huge Jupiter styles planets in low orbit around their stars. It’s pretty clear that they fell down there, destroying the entire inner system in their path.

Other notions threaten life; gamma ray explosions, supernovas, and simply passing next to another star, throwing a solar system into chaos, and some Jupiters down into a fatal spiral. Our Sun, though, is pretty much cruising far from any star, in a cosmic void right now, perhaps left by a supernova explosion. Maybe we have been lucky for 4 billion years.

***

COSMIC GRANDEUR VERSUS MONKEY BUSINESS:

Many a physicist, or cosmologist, talks about the beginning of time, and other various notions pertaining to the grandest imagined machinery of the universe, as if they had found God, and it was themselves they were looking for (as Obama would put it). They claim to know their garden, the universe, pretty well (having apparently being there, at the moment of creation).

Verily, what we know for sure is what we see in pictures, and that’s plenty:

Hubble Ultra Deep Field: 10,000 galaxies. How many men?

Notions such as the “edge of the universe” are much less scientifically robust than some scientists claim. When some talk about the “First Three Minutes”, one can only laugh, even if countless Nobel Prizes in physics subscribe to the notion. Physics is relative, the search for glory, absolute. At least so do monkeys behave.

The concept of time in Quantum Mechanics and Relativity are in complete contradiction. One is absolute, the other relative. So nobody knows for sure what time is, and what is truly its relation to space (nor do we know what space is, much beyond the pretty pictures given by the telescopes). Speaking of the history of time is completely meaningless, except as poetry. Or scientific sounding poetry. Too many holes in the logic.

Even using standard science to buttress one’s reflection, the size of the universe could well be at least a 1,000 bigger than the 14 billion light year piece that we presently observe. In truth, we have literally no idea. Even when sticking to conventional theory, which predicts only one thing in that respect, namely that the universe is bigger than what we see (it predicts it by requiring it actually, see below).

Another thing is sure: it’s incredibly immense out there, and not just in physical size, but also in conceptual size. We know lower bounds for the universe in size and complexity, but have no idea whatsoever about the upper bounds. Dark Energy is a perfect example. Fifteen years ago, Dark Energy was unknown. Now it makes up 74% of the mass of the universe.

***

PRESENTING SCIENTIFIC PHILOSOPHY AS SCIENCE IS NOT WISE:

It is not a good thing when highly uncertain science is presented as certain, just as much as really true parts of science. It is not just immodest. It undermines, and threatens, science deeply.

Because presenting as certain what is not so is just a lie. But science is truth, and that is why society supports it.

To present as true what is not so ridiculizes the notion of certainty. When, ultimately, the ineluctable collapse of immodest pseudo-certainty occurs, all of science gets slashed with doubt. American witches can run as republican candidates for the US Senate on completely crazed platforms, mumbling about mice with human brains (this happened in the last USA election). Scientists ought not to make craziness respectable by leveraging it themselves. Crazy is crazy, especially when a scientist does it. It’s craziness squared.

Make no mistake: speculation is central to science and even more to philosophy. Just speculation ought to be labeled as such. When I talk about my own TOW theory, I do not present it as fact and certitude.

Most of recent (last 120 years) physics was totally unexpected. A lot of it is true, no doubt, in some sense. Some of it is completely false, too, most probably, in the most fundamental sense. The more fundamental science gets, the more it gets subjected to representations which can be misleading. Thus when some physiology or solid state physics gets established, it will not be shattered. Not so for Quantum Field Theory (most of which being an extrapolation over an energy domain where it has not been tested).

Science, like philosophy, is not just a body of knowledge, but also a method. Both have to use common sense as much as possible. Philosophy uses the external edge of knowledge, the first inklings, the first warnings, the smallest indices, the irreproducible experiments. Thus any scientist searching for really shattering new science will pass through the philosophical method, as a mandatory passage to greater certainty.

When science is proclaimed, it has to be certain. Science is truth in which one can have faith. A lot of the most glitzy cosmology comes short of that. (Thus the adventures of the alleged Big Bang should not be used as an argument to fund expensive accelerators: there are enough good reasons to fund them, not to use the bad ones!) The surest part of cosmology is actually its pretty pictures.

***

INFLATE OUR CLAIMS, IF THE OLD ONES DID NOT WORK OUT:

All of recent conventional cosmology’s biggest and noisiest concepts rest on something called the Inflaton Field. One could say that it is just as much a rabbit out of a hat as in the best circus acts. There is no justification for it, except to explain what we see: something very big, very homogeneous, apparently contradicting relativity. The universe in its entirity.

The mystery that Cosmic Inflation tries to explain was this: as new regions of the universe come into view (at the speed of light!), it is observed that the new regions are exactly as the region we already know; same aspect, same background temperature, etc. How did they know how to look the same? They could not have talked to each other! Light did not have time to go from one to the other!

According to standard Einsteinian relativity, our region, and those regions, some on the opposite side of the universe from each other, have no common history! (Those new regions which appear are NOT within our past light cone… To use relativity lingo.)

In the USSR, Einstein’s work was criticized in minutia, for ideological reasons (Note1). So the great astrophysicist Zeldovitch came up in 1965 with the idea of inflation (the discovery is attributed to Guth, 1980, in the USA, because the USA buried the USSR, and America is a super power blessed by God, as the resident of the White House reminds his flock every day).

Einstein’s Relativity speaks of the speed of light within space, but not of the speed of space (so to speak). Speed of light is limited within space, speed of space is not limited. So it was breezingly supposed space had inflated at a gigantic speed, before slowing down. So the new regions coming into view had a sort of common history, after all.

From a philosophical perspective, to invent an explanation to explain a specific effect is called an ad hoc hypothesis. It can be a correct way to advance science, if it has predictive power (But differently from the neutrino, or the W, or the Higgs, how do you check for it? Finding the Inflaton particle? The Inflaton is supposed to have given birth to most other particles). In the meantime, it provides some hand waving to explain away an otherwise obvious contradiction with Relativity.

But it is not enough that some of the best theories in physics are weird, with the logical consistency of gruyere.

The apparent discovery of Dark Matter and especially Dark Energy, have brought a new twist. Dark Energy is completely unexplainable.

Dark Energy attracted attention to the fact that Quantum field theory is both the most precise and the most false theory ever contemplated (QFT is off in its prediction of vacuum energy by a factor of ten to the power 120, or so, the greatest mistake in theory, in the entire history of hominids… it would make even baboons scream in dismay.)

Billions of galaxies can be seen when we look as far as we can see. Here is a tiny detail, as far as we can see, without using a gravitational lens. [NASA-ESA Hubble]. Baffling. We are going to need a bigger imagination.

It’s hard for me to escape the feeling that the universe is much older than what standard cosmology believes, as I look at these very ancient, but very diverse galaxies in a piece of sky (Note 2).

Dark energy was discovered when it was realized, in super novae studies, that the universe’s expansion was accelerating (so energy is injected).

A natural question, though is this: ”If, as it turned out, the expansion is accelerating now, maybe it was at standstill much earlier?” Then the universe, even the small piece we can see, would be older and bigger than we have imagined so far. Don’t be afraid of the simple questions. Einstein asked himself at 16 what would happen if he looked at a mirror when going at the speed of light (Note 1).

Time will tell, as long as astronomy gets massively funded. Astronomy (astrophysics, cosmology, etc.) is one of the fields of science where fabulous progress is certain if it gets funded enough (the breakthroughs it made and will make in basic technology, to design the new instruments are very useful to the rest of society too).

In any case, the national debt is secure: it has a long way to go, before it can fill up the entire universe…

***

Patrice Ayme

***

Note 1.

Einstein’s views on space and time came under the label “Theory of Relativity”. That incorporated Lorentz’s work on the correct space-time transformation group compatible with Maxwell equations.

That is why looking at a mirror will not work, at the speed of light, if the conventional addition of speed used by Galileo was really true, because light could not catch up: light could not be seen at the speed of light (just as sound cannot be heard if one goes away from it at the speed of sound). So Galilean Relativity did not work (the first scientists who pointed that out were not Einstein, but Lorentz, Fitzgerald, and Poincare’, among others; Lorentz got the Nobel Prize for it).

Soviet scientists were irritated by the exaggeratedly sounding “Relativity” (since only Marx was absolute). They pointed out that the “Theory of General Relativity” should be called the “Theory of Gravitation”, and then they made more pointed critiques.

Ideology is important in science. The “multiverse” theory, a support of string theory, is a case in point. The multiverse ideology exists, because string theory has nothing to say about the measurement process, so it sweeps that inconvenient truth below an infinity of rugs. The multiverse cannot be fought scientifically, because it is not science. But it is philosophically grotesque, since it consists in claiming that all lies are true, somewhere else.

***

Note 2

The oldest galaxy was detected by Europeans at the Very Large Telescope in the high Chilean desert, in 2004, using a galactic super cluster as a lens (giving the VLT an aperture between 40 and 80 meters), had a redshift of 10, with an apparent age of more than 13 billion years.

***

Note on the notes: What did Einstein do in Relativity? He used an axiomatic method, with two axioms only (Principle of modern Relativity and Constancy of Light Speed).

Both axioms had been proclaimed by Poincare’, as Einstein knew, but Poincare’ had not realized that, with these two axioms only, all the known formulas could be derived in a few pages, as Einstein did (after doing away with the “Ether”, the substance in which waves were supposed to be waving). Einstein said he was influenced by empiricist philosophy from Hume and Mach.

The final story has not been written yet: and if the waves made the space? (TOW.)

V838 Monocerotis

Awesome! Plain and simply awesome.

From the Hubble website. Here’s the description of the image:

“Starry Night”, Vincent van Gogh‘s famous painting, is renowned for its bold whorls of light sweeping across a raging night sky. Although this image of the heavens came only from the artist’s restless imagination, a new picture from the NASA/ESA Hubble Space Telescope bears remarkable similarities to the van Gogh work, complete with never-before-seen spirals of dust swirling across trillions of kilometres of interstellar space.

This image, obtained with the Advanced Camera for Surveys on February 8, 2004, is Hubble’s latest view of an expanding halo of light around a distant star, named V838 Monocerotis (V838 Mon).

The illumination of interstellar dust comes from the red supergiant star at the middle of the image, which gave off a flashbulb-like pulse of light two years ago. V838 Mon is located about 20,000 light-years away from Earth in the direction of the constellation Monoceros, placing the star at the outer edge of our Milky Way galaxy.

Credit:

NASA, the Hubble Heritage Team (AURA/STScI) and ESA

Here are my thoughts.

A single light-year is approximately 6 trillion miles, or 9,460,730,472,580.8 kms for the metric brigade! Thus 20,000 light-years is 120,000 trillion miles, or 120,000,000,000,000,000 miles.

It is beyond imagination – yet it is real!

It humbles one beyond measure that in this short lifetime on mine, science has reached out so far. And then one looks more closely to home and remains appalled that we have learnt so little about living in peace and with integrity on this funny third rock from the Sun.

The ultimate paradox!

By Paul Handover

What is the Great Filter?

We’ve already survived some ‘filters’

A Great Filter of our own making

Unchecked population growth

Nuclear war

Pathogens and pandemics

Artificial intelligence

Asteroid and comet impacts

Climate change

Avoiding the Great Filter

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