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When Galaxies Collide
You’ll never look up at the night sky in the same way
"Why is the Milky Way blue? Why isn’t a black hole dark? How many stars can you see with your naked eye?* How much hotter are blue stars than red ones?**
Humans are the only known astronomers in the universe. When we look up at the night sky, we are linked to our ancestors. Away from city lights, we can see what generations of people before us have wondered at and weaved stories around.
But all that will change. The Andromeda Galaxy is rushing towards us at 400,000 kilometres an hour.
When Galaxies Collide will guide you to look at the night sky afresh. It peers 5.86 billion years into the future to consider the fate of Earth and its inhabitants. Will the solution be to live in space without a planet to call home? Will one of the other 100 billion planets spawn life?
Learn how to watch this space.
* 9,000, but only half of that from any given point on Earth.
** 38,000 degrees vs 3,000."
"Why is the Milky Way blue? Why isn’t a black hole dark? How many stars can you see with your naked eye?* How much hotter are blue stars than red ones?**
Humans are the only known astronomers in the universe. When we look up at the night sky, we are linked to our ancestors. Away from city lights, we can see what generations of people before us have wondered at and weaved stories around.
But all that will change. The Andromeda Galaxy is rushing towards us at 400,000 kilometres an hour.
When Galaxies Collide will guide you to look at the night sky afresh. It peers 5.86 billion years into the future to consider the fate of Earth and its inhabitants. Will the solution be to live in space without a planet to call home? Will one of the other 100 billion planets spawn life?
Learn how to watch this space.
* 9,000, but only half of that from any given point on Earth.
** 38,000 degrees vs 3,000."
186 pages, Kindle Edition
First published July 30, 2018
12 people are currently reading
196 people want to read
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Displaying 1 - 12 of 12 reviews
February 23, 2019
An astonomer's story of love with the universe. 'Star storm chasing' turns out to be exhilarating.
Very simple and intrigating account of things out their and various related concepts, including the Cepheid variables, parallax, the standard candle, blue stragglers, event horizon and, of course, the galactic bar.
Q:
Have we lost our connection with the night sky? (c)
Q:
Can you remember the very first time you looked up at the night sky? (c)
Q:
As my interest in astronomy came to light at the age of twelve, it added a universal dimension to my experiences. I learned, slowly at first, the appearance of the night sky and watched, fascinated, as the stars changed throughout the seasons. In summer, the bright trio of Vega, Deneb and Altair dominated the sky. In winter, Orion came to visit. Every night the sky circled steadily around the North Pole Star, also known as Polaris. Although I never knew him, this was the same night sky that my grandfather, also an astronomy enthusiast, had enjoyed. (c)
Q:
As I learned the constellations that he had taught my dad, it felt as if the night sky was something bigger than ourselves—something that connects us to our ancestors.
This connection to nature and to the stars helped me find my place in the world. (c)
Q:
I was the village kid who didn’t go to school—I taught myself at home from the age of eleven—and spent my days climbing trees, wandering the countryside and looking at the stars. (c)
Q:
We were undistracted, connected to our surroundings and navigating by the star that had created us. We felt free. Empowered by a basic knowledge of the sky... (c)
Q:
A hedgehog scuttled by. (c)
Q:
... the night sky is literally in our DNA. After all, every atom of carbon, nitrogen and oxygen in our bodies was created by the nuclear fusion of lighter elements in the centre of a star. Biologists might argue the phrasing of this point, but it is true to say that from a physical and chemical point of view we are literally descended from the stars—they are our parents and our creators. (c)
Q:
For our watered-down city view of the night sky we have light pollution to thank, which sees an estimated 35 per cent of all energy used in street lighting going to waste by poorly directed light shining up into the sky. (c)
Q:
As the hydrogen fuel runs out, it turns to helium, then to carbon, neon and oxygen, then finally to silicon as a source of fuel. Each step produces greater and greater heat in the core of the star. The final silicon fusion reactions burn furiously at a temperature of 3 billion degrees Celsius for only one day, in which time nickel-56 is formed in a process called silicon burning. The nickel quickly undergoes radioactive decay into iron. Due to the chemical nature of iron, it takes more energy to burn than it releases—in other words, it is a hopeless fuel. At this point there is literally nothing left to burn and the core of the star collapses under its own weight at a velocity of 70,000 kilometres per second. Its temperature hits 5 billion degrees Celsius and it becomes so squashed together that all the electrons and protons combine to form neutrons (the neutrally charged particles in the nuclei of atoms). Finally, the core becomes so dense (equivalent to the density of an atomic nucleus) that a very powerful force called neutron degeneracy pressure kicks in, slamming on the brakes. The enormous energy of the core collapse is halted and the incoming material rebounds outwards. The star’s material is expelled at about 30,000 kilometres per second, and the star goes supernova. (c) Sounds exciting!
Q:
The next dramatic supernova was seen on 30 April 1006 CE. It shone incredibly brightly for several years and dominated the night sky. The scholars of the time wrote that it was so bright it was even visible during the daytime. Chinese records describe it as ‘huge … like a golden disc’ and ‘like the half-moon … it had pointed rays’. One account said that you could read a book by its light. The star was so brilliant it appeared in records throughout the world, from Japan and China to the Middle East, Africa and parts of Europe. It was one of the most extraordinary sights in the night sky ever witnessed by humans. (c)
Q:
Q. Where does an astronaut go to drink?
A. The space bar. (с)
Q:
We search for rare gems—the platypus and the toucan, the weird and wonderful types. We witness snapshots of galactic collisions between grand spirals, and the creation of brilliant fields of new stars. We see the battered shells of mangled hybrid galaxies and piece together the lives of elliptical galaxies—the bloated elders of the skies. This amazing galaxy menagerie is giving us new insights into the creativity of the cosmos. (c)
Q:
Red stars have surface temperatures of more than 3000 degrees Celsius, but that is nothing compared with a hot massive blue star, whose surface temperature comes in at a snuggly 30,000 degrees Celsius. (c)
Q:
I don’t know what scared me more during the three-and-a-half-hour drive: the unconstrained speeds of the German cars overtaking us on the autobahn, or the prospect of two and a half more hours of my colleague’s religious folk music. Still, after winding our way through the vineyards of North Rhine-Westphalia and doubtless earning God’s blessing with our musical devotion, we arrived safely at the observatory. I was struck by the sharp contrast between the bright sunshine of the surrounding countryside and the cool, dark valley that is home to the telescope. (с)
Q:
Scientists learn to be resilient in such circumstances. Countless hours of astronomical observations yield null or unremarkable results, but these are not mistakes. Searching and not finding is a result in itself. We learn about nature’s limits from this process. What some might call failure is a vital part of the scientific quest for something special that will deliver us new insight into the workings of the universe.
Q:
Two horses grazed by the airstrip, ‘Hello!’ I boomed cheerily, and received a curious flick of the ears in return. I’ll let you into a little secret: I often talk to animals on my runs. A wallaby surprised me once as I turned a corner on a training run, and instinctively I said, ‘Hello, gorgeous’ to the magnificent little creature whose doe-eyed presence had interrupted my stride. Unfortunately, I was running with my friend Dr Jess Baker, a psychologist and worldclass ultra-marathon runner. I always worry about what I say around psychologists in case they are analysing me. Luckily I didn’t have to worry about that—in her typical enthusiastic style, Jess burst out: ‘Ohmigosh! I thought it was just me who talked to animals!’ So I’m not the only one, then. (c)
Q:
Wherever I travel in the world, I love exploring on foot. Running connects me with the real sights, sounds and smells of a place. Whether it’s a crisp trot through the forests of the Netherlands, a jog through paddy fields in Bali dodging rabid dogs and monkeys, or a noisy and sweaty dash through the mad traffic of Kuala Lumpur, an early morning run gives me the freedom and ability to explore that I just can’t get with a taxi ride. (c)
Q:
I decided to go left and quickly my mind wandered into one of my regular fantasies of running solo from here to the coast. (c)
Q:
Our epoch on Earth is auspicious, too. We live around a stable star in the middle of its lifetime that provides the perfect conditions for our existence. By a bewildering coincidence, the moon lines up regularly and perfectly with the sun, providing mind-blowing eclipses for us to enjoy. Meteors rain down on our planet with regularity, providing a safe yet intimate congress with the fourbillion-year-old dust from which our solar system was born. Planets dance through our skies, twirling around the sun with pace and tempo that reveal their positions in the cosmic order. Galaxies poke through the cloak of invisibility and reveal hints of the vast scale of our cosmos. Humans still walk among us who have broken the bonds of Earth’s gravity and have stood on the face of the moon.
We are all children of the universe, and it’s time to meet the family. Next time the sky is clear, get a star map (or an app), grab someone you love and take a walk under the stars. Go out into the backyard and get acquainted with your celestial neighbours. Marvel at the sparkling planet Venus. Consciously observe the changing of the moon’s phases. Take a drive into the country with a flask of coffee and a blanket and treat yourself to the dramatic spectacle of the universe. Sit and wonder and imagine like your ancestors did. Because for your descendants in a few billion years, this will all have been blown away. (c)
Very simple and intrigating account of things out their and various related concepts, including the Cepheid variables, parallax, the standard candle, blue stragglers, event horizon and, of course, the galactic bar.
Q:
Have we lost our connection with the night sky? (c)
Q:
Can you remember the very first time you looked up at the night sky? (c)
Q:
As my interest in astronomy came to light at the age of twelve, it added a universal dimension to my experiences. I learned, slowly at first, the appearance of the night sky and watched, fascinated, as the stars changed throughout the seasons. In summer, the bright trio of Vega, Deneb and Altair dominated the sky. In winter, Orion came to visit. Every night the sky circled steadily around the North Pole Star, also known as Polaris. Although I never knew him, this was the same night sky that my grandfather, also an astronomy enthusiast, had enjoyed. (c)
Q:
As I learned the constellations that he had taught my dad, it felt as if the night sky was something bigger than ourselves—something that connects us to our ancestors.
This connection to nature and to the stars helped me find my place in the world. (c)
Q:
I was the village kid who didn’t go to school—I taught myself at home from the age of eleven—and spent my days climbing trees, wandering the countryside and looking at the stars. (c)
Q:
We were undistracted, connected to our surroundings and navigating by the star that had created us. We felt free. Empowered by a basic knowledge of the sky... (c)
Q:
A hedgehog scuttled by. (c)
Q:
... the night sky is literally in our DNA. After all, every atom of carbon, nitrogen and oxygen in our bodies was created by the nuclear fusion of lighter elements in the centre of a star. Biologists might argue the phrasing of this point, but it is true to say that from a physical and chemical point of view we are literally descended from the stars—they are our parents and our creators. (c)
Q:
For our watered-down city view of the night sky we have light pollution to thank, which sees an estimated 35 per cent of all energy used in street lighting going to waste by poorly directed light shining up into the sky. (c)
Q:
As the hydrogen fuel runs out, it turns to helium, then to carbon, neon and oxygen, then finally to silicon as a source of fuel. Each step produces greater and greater heat in the core of the star. The final silicon fusion reactions burn furiously at a temperature of 3 billion degrees Celsius for only one day, in which time nickel-56 is formed in a process called silicon burning. The nickel quickly undergoes radioactive decay into iron. Due to the chemical nature of iron, it takes more energy to burn than it releases—in other words, it is a hopeless fuel. At this point there is literally nothing left to burn and the core of the star collapses under its own weight at a velocity of 70,000 kilometres per second. Its temperature hits 5 billion degrees Celsius and it becomes so squashed together that all the electrons and protons combine to form neutrons (the neutrally charged particles in the nuclei of atoms). Finally, the core becomes so dense (equivalent to the density of an atomic nucleus) that a very powerful force called neutron degeneracy pressure kicks in, slamming on the brakes. The enormous energy of the core collapse is halted and the incoming material rebounds outwards. The star’s material is expelled at about 30,000 kilometres per second, and the star goes supernova. (c) Sounds exciting!
Q:
The next dramatic supernova was seen on 30 April 1006 CE. It shone incredibly brightly for several years and dominated the night sky. The scholars of the time wrote that it was so bright it was even visible during the daytime. Chinese records describe it as ‘huge … like a golden disc’ and ‘like the half-moon … it had pointed rays’. One account said that you could read a book by its light. The star was so brilliant it appeared in records throughout the world, from Japan and China to the Middle East, Africa and parts of Europe. It was one of the most extraordinary sights in the night sky ever witnessed by humans. (c)
Q:
Q. Where does an astronaut go to drink?
A. The space bar. (с)
Q:
We search for rare gems—the platypus and the toucan, the weird and wonderful types. We witness snapshots of galactic collisions between grand spirals, and the creation of brilliant fields of new stars. We see the battered shells of mangled hybrid galaxies and piece together the lives of elliptical galaxies—the bloated elders of the skies. This amazing galaxy menagerie is giving us new insights into the creativity of the cosmos. (c)
Q:
Red stars have surface temperatures of more than 3000 degrees Celsius, but that is nothing compared with a hot massive blue star, whose surface temperature comes in at a snuggly 30,000 degrees Celsius. (c)
Q:
I don’t know what scared me more during the three-and-a-half-hour drive: the unconstrained speeds of the German cars overtaking us on the autobahn, or the prospect of two and a half more hours of my colleague’s religious folk music. Still, after winding our way through the vineyards of North Rhine-Westphalia and doubtless earning God’s blessing with our musical devotion, we arrived safely at the observatory. I was struck by the sharp contrast between the bright sunshine of the surrounding countryside and the cool, dark valley that is home to the telescope. (с)
Q:
Scientists learn to be resilient in such circumstances. Countless hours of astronomical observations yield null or unremarkable results, but these are not mistakes. Searching and not finding is a result in itself. We learn about nature’s limits from this process. What some might call failure is a vital part of the scientific quest for something special that will deliver us new insight into the workings of the universe.
Q:
Two horses grazed by the airstrip, ‘Hello!’ I boomed cheerily, and received a curious flick of the ears in return. I’ll let you into a little secret: I often talk to animals on my runs. A wallaby surprised me once as I turned a corner on a training run, and instinctively I said, ‘Hello, gorgeous’ to the magnificent little creature whose doe-eyed presence had interrupted my stride. Unfortunately, I was running with my friend Dr Jess Baker, a psychologist and worldclass ultra-marathon runner. I always worry about what I say around psychologists in case they are analysing me. Luckily I didn’t have to worry about that—in her typical enthusiastic style, Jess burst out: ‘Ohmigosh! I thought it was just me who talked to animals!’ So I’m not the only one, then. (c)
Q:
Wherever I travel in the world, I love exploring on foot. Running connects me with the real sights, sounds and smells of a place. Whether it’s a crisp trot through the forests of the Netherlands, a jog through paddy fields in Bali dodging rabid dogs and monkeys, or a noisy and sweaty dash through the mad traffic of Kuala Lumpur, an early morning run gives me the freedom and ability to explore that I just can’t get with a taxi ride. (c)
Q:
I decided to go left and quickly my mind wandered into one of my regular fantasies of running solo from here to the coast. (c)
Q:
Our epoch on Earth is auspicious, too. We live around a stable star in the middle of its lifetime that provides the perfect conditions for our existence. By a bewildering coincidence, the moon lines up regularly and perfectly with the sun, providing mind-blowing eclipses for us to enjoy. Meteors rain down on our planet with regularity, providing a safe yet intimate congress with the fourbillion-year-old dust from which our solar system was born. Planets dance through our skies, twirling around the sun with pace and tempo that reveal their positions in the cosmic order. Galaxies poke through the cloak of invisibility and reveal hints of the vast scale of our cosmos. Humans still walk among us who have broken the bonds of Earth’s gravity and have stood on the face of the moon.
We are all children of the universe, and it’s time to meet the family. Next time the sky is clear, get a star map (or an app), grab someone you love and take a walk under the stars. Go out into the backyard and get acquainted with your celestial neighbours. Marvel at the sparkling planet Venus. Consciously observe the changing of the moon’s phases. Take a drive into the country with a flask of coffee and a blanket and treat yourself to the dramatic spectacle of the universe. Sit and wonder and imagine like your ancestors did. Because for your descendants in a few billion years, this will all have been blown away. (c)
January 2, 2021
I received this signed copy after attending a Children’s Book Council Australia (CBCA NSW) event where the author spoke.
While I enjoyed the easy nature of this gentle narrative, the nuts and bolts of astronomy didn’t engage me.
A book I feel proud to be able to say I’ve read, but much of which will not linger long in my memory. The Smith cloud looks fascinating, but by bedtime tonight I doubt I’ll be able to recall one fact about it....
Lisa Harvey-Smith writes with economic clarity and warmth. An author I feel I should read more of and make an effort to push myself to learn more about our universe.
While I enjoyed the easy nature of this gentle narrative, the nuts and bolts of astronomy didn’t engage me.
A book I feel proud to be able to say I’ve read, but much of which will not linger long in my memory. The Smith cloud looks fascinating, but by bedtime tonight I doubt I’ll be able to recall one fact about it....
Lisa Harvey-Smith writes with economic clarity and warmth. An author I feel I should read more of and make an effort to push myself to learn more about our universe.
February 1, 2019
Inspirational. A wonderful cosmic journey with a most engaging scientist, who can both write and speak well.
August 19, 2018
An excellent summation of the universe as we know it and the fate of our galaxy!
October 19, 2018
It was a good book, and Lisa is an awesome person!
I like space, what more can I say?
I like space, what more can I say?
July 13, 2022
Whilst I had to concentrate pretty hard to digest this, I gained a lot from reading this book. I feel like I understand the universe a lot better. I have realised I am a visual thinker and I would have found this information easier to digest visually. Some of the take home messages regarding what is the future of our galaxy, what can we do to stop light pollution hampering our connection to the universe and is there any other life out there, were fascinating to ponder. Lisa is a great writer to draw all of this information together and communicate as clearly as she does to people like myself.
October 11, 2018
A well-written (easy to read) round-up that would be a good introduction for anyone interested in stars, galaxies and a fair range of astronomical issues. I found it a tad tedious in a few chapters (as I was well-aware of about 90% of the issues raised) and had to skip ahead, but enjoyed the personal bits that gave it a life. We do indeed live in a universe that is far weirder than we can possibly image. Take our very (VERY!) local 'neighbourhood' 'Milky Way galaxy at around 100,000 light years across!
December 23, 2023
A very interesting book about an author who clearly loves where her career has taken her.
Whilst I may not be able to recite the vast majority of galactic features that Harvey-Smith has presented to the reader, I am still in awe of the unbelievable extent of our universe and the scope of research and exploration that has been opened to modern astronomers through technology and ingenuity.
Whilst I may not be able to recite the vast majority of galactic features that Harvey-Smith has presented to the reader, I am still in awe of the unbelievable extent of our universe and the scope of research and exploration that has been opened to modern astronomers through technology and ingenuity.
April 13, 2019
A book about cool stuff in space interspersed with fun anecdotes about the astronomer life.
May 9, 2020
The universe is pretty mind-blowing.
November 12, 2021
Very informative, with some insights into the life of an astrophysicist
January 2, 2023
Really good book. I loved how the universe and astronomy facts were presented in stories about the author. Did I understand everything? No. Did I sign up for Galaxy zoo? Absolutely.
Displaying 1 - 12 of 12 reviews