Krishna
The passion for the universe comes out bright and clear. The language is nice and the material impressive, for a layman to read. Inured to details by reading a lot o astronomy books, I found learning new material – how comets come to be, for example but even when I was not learning, was swept away joyously in the flowing tide of prose from this author who has the ability to inspire readers like me.
He talks of Aristosthenes of Egypt in pre Christ days, and how he was a great polymath. From the mere fact that in Syene in Egypt sticks cast no shadows at noon and the fact that in Alexandria, where he lived, they do, he managed to calculate the circumference of the earth using just measurements and his brain! Done more than 2400 years ago now, it is still remarkably close to the actual number!
You also learn some fun trivia along the way, when they talk about Alexandria’s library and the attached museum, we learn that the museum was so named because it was dedicated to the Nine Muses of legends.
Even though the book is about Cosmos, it delightfully wanders into other areas. For instance, the author talks of selective breeding in “Samurai” crabs off the coast of Japan or domesticated crops and animals.
Also fascinating is the explanation on why the ancient civilizations were interested in astronomy. The fact that it was ‘life and death’ for them is a new concept to me and makes sense once we are made to see for ourselves!
We learn that the term menstrual (as in, yes, the period) comes from the root word denoting ‘the moon’. Other etymological finds in this book include ‘disaster’ which comes from Greek from ‘bad star’, influenza from Italian for influence and Hebrew mazeltov for ‘good constellation’. The word consider came from root words meaning ‘with the planets’. All originated with old astrology.
Kepler was a seminary and he was sure that he was ‘not in the grace of God’ as he had too many sins to atone for! However, being brilliant of mind, and interested in astronomy, he proposed several firsts. He proposed that other planets were made of the same material as earth. And astoundingly, since telescopes were not yet in use, he proposed that planets rotate in an elliptical orbit!!
Even though we reviewed a book on the life of Newton himself called Newton and the Counterfeiter – OK, not his biography but it covers many details of his life – we learn new facts about his life here. For instance, the author reveals that Newton was a virgin all his life. Also we hear of the speculation that his erratic behaviour may have been due to ‘heavy metal poisoning’, including self ingestion of small amounts of mercury and arsenic. (Using the sense of taste as a common analytic tool of chemists in those times).
The superstitions about comets are interesting to read. That is not all. We learn other astonishing trivia too. Venus, for example, rotates once in every 243 (earth) days and so a ‘day’ in Venus is like 243 days on earth. In addition, Venus is the only planet in our solar system that rotates the other way from all other planets including earth and so the sun over there rises in the west and sets in the east, about 113 earth days later. The surface temperatures of Venus are about 480 degrees Celsius.
It is fascinating that the Soviets who have sent successfully unmanned spaceships to Venus to take measurements, could not repeat the feat successfully in Mars, which has a much more ‘earth like’ features. Venus is a hot hellhole by Earth standards. It appears that the best guess for a culprit for the failed Mars landings is the crazy speed of wind (in a dust storm) which was too much for the space equipment to survive. Fascinating details!
It even explains the anti globalization feeling that swept the world and the clear causes for it. Especially in light of the EU expansion to East European countries.
If you squint a little – for this book covers the history until 2005 – you can even see the root causes for the later Brexit vote and the result in the descriptions of inequality within the UK.
The hamhanded efforts of the French to ‘save their language’ for example passing a law that ‘if anyone – even outsiders – had a conference on French soil, the language of communication must be French’ would be comical if not for the devastation it caused by people choosing other locations for their conferences and loss of revenue for France.
The speculation on life in Mars, even if microbial, is interesting. So is the musings on whether we can live on Mars. (A thought later famously expressed by Elon Musk).
We learn that Voyager 2, the unmanned craft that was sent to Venus, could not be powered by solar energy because its mission takes it so far from the sun and therefore is powered by nuclear energy.
Voyager 2 also shed light on one of the Jupiter’s moon called Io (pronounced ee-yo) that was entirely made of effluvia from volcanoes and spewing different coloured sulfur, altering the landscape regularly.
And we learn that Jupiter itself, had it been more massive, would have been a star like the sun!
Already, it gives out twice the energy it receives from the sun, although it is all in infrared. If it had been a full star, then we would live in a world with two suns, with night coming but rarely!
The core of Jupiter is a sloshing sea of liquid hydrogen – impossible to produce on earth anywhere due to the pressures required to make it.
A moon of Saturn, called Titan is the biggest moon in our solar system. Saturn is smaller than Jupiter, notwithstanding the ‘rings’ around it. Titan is a moon with a substantial atmosphere!
The surprisingly red colouration of Titan is due to organic molecules, is the best guess today.
The pythagoreans knew that there were six regular solids. One of them, the dodecahedron (twelve sided in Latin) was assumed to represent the entire Cosmos and was considered dangerous to learn about. Out of the other five, four were supposed to represent the ‘four elements’ that make up everything – earth, fire, water and wind. The fifth was supposed to represent another element ‘yet unknown to humans’. The word quintessence comes from these thought process.
In the same way, Pythagoras assumed that everything in the world could be derived from whole numbers or integers. When ironically, using Pythagorean theorem, they found that the square root of 2 cannot be expressed as a ration of any two numbers at all, they were shocked. Initially the word ‘irrational’ denoted numbers which cannot be expressed as a ratio of any two whole numbers; consequently, the second meaning of ‘threatening or dangerous’ originates from these times.
Some ideas that we already knew are brought into a sharp perspective by the author. How about this sample? ‘If you grab a handful of sand in a beach, there are about 10000 particles in your hand. The number of stars in the universe exceeds all the grains of sand in all the beaches on Earth’. Amazing.
We also learn that the word zodiac comes from a root word for animal because many of the zodiac signs (and constellation of stars) comes from animals. (My snarky mind asks ‘What about libra or gemini?’ but largely in compliance! Even Gemini could be ‘animal’ because humans are fundamentally animals, right?)
The nearest ‘star system’ to earth is a constellation called Alpha Centauri. It is a package of three stars, really. Two of those stars revolve around each other but a third, called Proxima Centauri revolves around the two at a ‘discrete distance’ as the author puts it. By the way, since this third star is ‘closest to the sun’ in spite of being light years away, it is named ‘Proxima’.
The second brightest star we see is from a constellation called Andromeda. The star itself is called Beta Andromedae. The light we see now was emitted seventy five years ago, due to the distance from us! As the author puts it ‘If Andromeda star blew itself up today, we will not know about it for seventy five years from now!’
The M31 galaxy (the centre of it, really) which is the nearest spiral galaxy to us is about 2 million light years away. Which means that the stars we see now emanated their light when humans had not evolved on earth!
Even more amazing, the distance from earth to the remotest quasars is about five to eight billion light years. The light we see now were sent before the earth and the Milky Way even had formed!
The author further states that ‘If you were wandering around Tuscan countryside in 1890s you may have seen a long haired teenage high school dropout. He was a dropout because his teachers asked him to leave school as ‘his questions were out of context and destroyed classroom discipline’. He obligingly left. His name was Albert Einstein.
From that point on, Sagan brilliantly explains the thought process that brought Einstein to the Theory of Relativity. Sagan makes it as accessible as possible to a layman and I invite you to read the book if you want to know more. As for me, I think it is one of the best descriptions i have read on – not the Theory of General Relativity itself but – the path Einstein took to reach there.
And on the way, he debunks the ‘speed of thought’ being proferred as being faster than the speed of light!
Einstein suggests some thought experiments that really, even after reading this and other books, make very little sense to me. For arguments sake, assume that the speed of light is, say 40 km per hour. And you have a scooter that can reach it. The book says (and probably Einstein said) that as you approach this speed, ‘you can see around corners and what is behind you shows up in front’. (Why?) Also it says that if a person on ground is watching you, your infrared will appear rid as it shifts to the low end of the visible spectrum (Again, why?). However (and this makes sense) if another is travelling at the same speed, say, on a pillion seat on the same bike, then for that person none of these effects will be visible. The author (glibly?) says that this can be proved through first year algebra so ‘available for anyone to understand’. Really?
I am so confused! He also says that if you travel at the speed of light, ageing slows down or even stops. I have at least read it in other books on Relativity. Again, hard to “logically” feel.
And even the theoretical speculation on what it takes to build an interstellar spaceship sounds like science fiction. You need to use the scarce hydrogen atoms as fuel; you need to ensure that, at close to speed of light, the ionized gamma radiation does not damage the ship! And so much more.
On another topic, again, Carl Sagan astonishes. Instead of the worm hole and cryogenic freezing theory that is the staple of galaxy hopping science fiction authors, he suggests that the theory of relativity and the time warping around the speed of light in itself may give humans in the future to traverse the galaxy. And the fascinating thing is that the earthlings they left behind or their descendents or the entire humankind will not be there to greet them upon their return to earth!
We also learn that new stars are born next to supernova explosions of existing stars. The explanation is thrilling to read. Also the explanation that even in the night, if you look at where ‘the sun would be’, that is down earthwards in a precise direction, neutrinos flood your eyes. They can pass through matter and through the earth, and then through you who is looking!
We have calculated that the “measured” amount of neutrinos is lower than would be predicted by mathematics. If neutrinos pass through everything, then how do you do experiments with it? Sagan provides the answer. However, why the observed amount is less than the predicted one is an unsolved mystery, at least when the book was published!
We also learn what happens when the sun eventually ‘dies’. The abundance on earth of some types of heavy atoms proves that there was a supernova explosion just before the Solar System was formed and thus the sun is a second or third generation star.
He also says that everything on earth – including llie itself, and us – started with the explosion of the supernova and the formation of the solar system. Fascinating thought.
And a collapsed star shrinks into itself, becoming a dense neutron star. The density creates internal reactions and have it emit bright light in the visible spectrum (plus invisible spectrums) once a rotation. If earth was in the line of sight, we may see a flash for every rotation – this is why these stars are named pulsars.
Neutron star ‘matter’ is so condensed that a teaspoonful would weigh as much as a mountain and if a piece should pass through earth, it will simply make a hole right through and emerge on the other side and keep going!
And to explain a black hole (which only massive stars become after “death” ) he explains with a “gravity altering machine” analogy. His thinking is excellent and you gain new perspectives on things that you assumed you already knew!
When black holes were thought of, by English astronomer John Michell (yes, that is how he spelt his name!) the idea was rejected because it seemed ‘too fantastical to be true’ until much later. The “physical observation” of a black hole (or, to put it correctly, the observations of the effects of an invisible black hole) in the constellation of Cygnus is brilliantly told.
What is a wormhole so loved by sci fi authors? Sagan explains! If you fall into a black hole (and somehow survive) and if the black hole is rotating (a very likely assumption) you may emerge in another space and another time. This is called a ‘worm hole’ like a hole in the apple that lets you go through the apple to the other side! But I cannot help think that this is not at all like the worm holes you read in science fiction books since you have no control of where you go or when (in time) you get there! As Sagan himself points out, this is a hypothesis and has never been proved. (Can it ever be?)
The author wonders (and takes us with him) if we have such awesome things in the known universe what wonders we may have not seen so far in the far parts of the universe? A thrilling and yet frightening thought.
We have read stacks on books about the Big Bang and its aftermath but this author makes it easily understandable. He talks about why galaxies formed after the Big Bang, which spewed mainly Hydrogen and Helium gas, and describes spiral galaxy formation (like ours) and elliptical galaxy formation. Breathtaking!
Our “backyard” consists of only two galaxies (a sparse place indeed), both of them spiral. We have our own Milky Way, of course, and the other is M31.
The author points out when two galaxies collide, the planets simply mostly pass through because most of the galaxy is void. But the gravitational forces of the stars and planets within them will distort each other. However, a direct impact can destroy either galaxy, sending the constituent stars careening through the intergalactic space ‘a galaxy wasted’ in the author’s words.
Galaxies form and decay and reform. Again, in the author’s words, ‘The suicide rate of galaxies is high’. Black holes are suspected in the midst of some specific giant galaxies.
Quasars are strange things. The name is because when astronomers were researching, they realized that not all radio waves are powerful radio sources, they called them ‘Quasi-Stellar Radio Sources’ which became quasars as a pronounceable acronym! There are five different hypotheses on what they are, so we will just assume ‘we don’t know’.
Another surprise is, that by finding a supercluster of Virgo, we may deduce that the Big Bang was “lumpier” than previously imagined (and can even be seen as two Big Bangs or more!).
He talks about various religions, old and new, which wondered about the creation of earth and lists many belief systems. He also mentions that the Hindu religion of ancient India is the only one which talks about ‘even Gods have deaths and rebirths’. Fascinating insight. While he claims that the Big Bang is also a theory like the religious theories, he expresses respect for the man’s curiosity and the depth of the ancient belief systems like the above.
He also describes why we need X Ray telescopes and other telescopes that peer into space at wavelengths invisible to human eyes. I cannot stress enough that, if you are interested in this subject at all out of curiosity, you will be immensely rewarded by reading this book!
The author laments human disruption of the life of whales – not just by slaughter, though there is that too despite the protected status of these intelligent giants but also through the regular noise of the human made steam ships which disrupt whale communication in a significant way through noise pollution.
He waxes eloquent in the praise of books and libraries – and that is understandable. To me, a more astonishing insight is his musings on why we have five fingers on each hand, how easily we could have had four or six fingers on each hand and what our arithmetic would have been like if this had happened!
Sagan also speculates that the bipedalism of humans in those far off days was probably caused by lack of trees, which in turn was caused by an as-yet-unknown climate change.
While Sagan argues that it is likely that, given the size of the universe, there is a high probability that there is life elsewhere, he suspects that it will be very different from us. We are who we are because of the survivalist pressures from large predators like dinosaurs suddenly eased, allowing mammals to occupy every niche left vacant, including the human niche.
There are so many gems in this book like this. In addition his description of Rosetta stone and the process by which the hieroglyphic writings on this and others were decoded is fascinating and a different from other descriptions I have read. A Frenchman called Champollion was responsible for finally deciphering the so far uncrackable hieroglyphics.
His speculation about advanced civilizations elsewhere in the universe is also fascinating and shows a scientific mind at work. He wonders if the contact, if it ever happens, will be peaceful or will it be ‘like Spaniards meeting the Aztecs for the first time’ utterly destructive to us?
The fallout of a nuclear war, should there be one, are horrifying to read because it is personalized to include eyewitness accounts of the aftereffects of Hiroshima at the end of WW II.
The forming of the stars and planets from nothing but hydrogen atoms is fun to read, and at least to me, a new way of explaining how the universe took shape by condensation. Explaining ‘known’ facts in a very new way is one of the great strengths of this book.
9/10
— Krishna