What do you think?
Rate this book
15 Million Degrees: A Journey to the Centre of the Sun
110 times wider than Earth; 15 million degrees at its core; an atmosphere so huge that Earth is actually within it: come and meet the star of our solar system
Light takes eight minutes to reach Earth from the surface of the Sun. But its journey within the Sun takes hundreds of thousands of years. What is going on in there? What are light and heat? How does the Sun produce them and how on earth did scientists discover this?
In this astonishing and enlightening adventure, you'll travel millions of miles from inside the Sun to its surface and to Earth, where the light at the end of its journey is allowing you to read right now. You'll discover how the Sun works (including what it sounds like), the latest research in solar physics and how a solar storm could threaten everything we know. And you'll meet the groundbreaking scientists, including the author, who pieced this extraordinary story together.
Light takes eight minutes to reach Earth from the surface of the Sun. But its journey within the Sun takes hundreds of thousands of years. What is going on in there? What are light and heat? How does the Sun produce them and how on earth did scientists discover this?
In this astonishing and enlightening adventure, you'll travel millions of miles from inside the Sun to its surface and to Earth, where the light at the end of its journey is allowing you to read right now. You'll discover how the Sun works (including what it sounds like), the latest research in solar physics and how a solar storm could threaten everything we know. And you'll meet the groundbreaking scientists, including the author, who pieced this extraordinary story together.
304 pages, Hardcover
Published March 31, 2016
35 people are currently reading
440 people want to read
Ratings & Reviews
Friends & Following
Create a free account to discover what your friends think of this book!
Community Reviews
Displaying 1 - 30 of 36 reviews
April 13, 2022
Fascinating book by an astrophysicist (and also apparently first female presenter of “The Sky at Night”) in her real area of academic expertise - the Sun and particularly one area in which she further specialises - so called “coronal mass ejections” and the changes in the Sun’s magnetic field which causes them.
The book being written by an academic (rather than a “popular science” writer) gives the book a lot of authenticity - while occassionally straying a little too far into the auto-biographical (scientists she has worked with, her own areas of interest and involvement). I also think it was quite an omission to have just black and white photos in the text - this felt like a book which needed a series of colour plates to bring it to life.
The first part of the book explains the basic make up of the sun and the way in which it produces the light we see on earth. This part is particularly fascinating for the way in which it relies on two (in probability terms) incredibly rare happenings (but taken from an enormous sample so that there are in fact lots of instances). This is explained well in this Guardian review of the book (https://amp.theguardian.com/books/201...).
Some of the subsequent sections I found rather heavy going - particularly those around flux rope formation - my lack of love for Physics (despite successfully taking an A Level in it), and particularly my lack of interest in magnetic fields was not a great match for the areas which both most interest the author and which I think are naturally the most complex to understand (even for scientists).
However sections on solar flares and solar wind were interesting (if also complex at times) and I particularly enjoyed the chapter on sunspot cycles (sunspots themselves having been covered in an earlier and relatively easy to follow chapter). What I found interesting here were her conclusions (given I would say slightly reluctantly given her views on the importance of the sun) that fluctuations in earth’s temperature due to sunspot cycles are completely swamped by the impact of man-made influences.
Later she goes on to discuss how it is becoming clear that the period over which scientific solar observations have been made has actually been an historically anomalous one with high solar activity and that actually more needs to be done to understand longer term solar cycles.
Finally at the start of the sunspot cycle chapter she quotes x(with no further detail at all as to who wrote it or where it was published) a headline from 2010 from a newspaper quoting an observer of sun-spot activity who claimed the sun was entering a period of reduced sun spot activity and (more controversially and less correctly) that a mini ice age would follow.
Now my antennae were alerted at this point - around 2010 I was involved in industry and professional working groups on the then emerging science on climate change/global warming, including working with a number of leading climatologists. Now I recall a certain attendee at some conferences who spoke on this topic (from the audience if not permitted a place on stage) - and I quickly Googled the topic to confirm who I thought the article was written by - correctly identifying it as Piers Corbyn (the then slightly better known eccentric brother of a relatively little known Labour MP - now of course rather better known for his anti-lockdown protests brother of an extremely well known ex-Labour MP). Even better though the first link that came up (https://amp.smh.com.au/environment/we...) was written by a then Mayor of London now known for his lack of compliance with his own laws.
The book being written by an academic (rather than a “popular science” writer) gives the book a lot of authenticity - while occassionally straying a little too far into the auto-biographical (scientists she has worked with, her own areas of interest and involvement). I also think it was quite an omission to have just black and white photos in the text - this felt like a book which needed a series of colour plates to bring it to life.
The first part of the book explains the basic make up of the sun and the way in which it produces the light we see on earth. This part is particularly fascinating for the way in which it relies on two (in probability terms) incredibly rare happenings (but taken from an enormous sample so that there are in fact lots of instances). This is explained well in this Guardian review of the book (https://amp.theguardian.com/books/201...).
Some of the subsequent sections I found rather heavy going - particularly those around flux rope formation - my lack of love for Physics (despite successfully taking an A Level in it), and particularly my lack of interest in magnetic fields was not a great match for the areas which both most interest the author and which I think are naturally the most complex to understand (even for scientists).
However sections on solar flares and solar wind were interesting (if also complex at times) and I particularly enjoyed the chapter on sunspot cycles (sunspots themselves having been covered in an earlier and relatively easy to follow chapter). What I found interesting here were her conclusions (given I would say slightly reluctantly given her views on the importance of the sun) that fluctuations in earth’s temperature due to sunspot cycles are completely swamped by the impact of man-made influences.
Later she goes on to discuss how it is becoming clear that the period over which scientific solar observations have been made has actually been an historically anomalous one with high solar activity and that actually more needs to be done to understand longer term solar cycles.
Finally at the start of the sunspot cycle chapter she quotes x(with no further detail at all as to who wrote it or where it was published) a headline from 2010 from a newspaper quoting an observer of sun-spot activity who claimed the sun was entering a period of reduced sun spot activity and (more controversially and less correctly) that a mini ice age would follow.
Now my antennae were alerted at this point - around 2010 I was involved in industry and professional working groups on the then emerging science on climate change/global warming, including working with a number of leading climatologists. Now I recall a certain attendee at some conferences who spoke on this topic (from the audience if not permitted a place on stage) - and I quickly Googled the topic to confirm who I thought the article was written by - correctly identifying it as Piers Corbyn (the then slightly better known eccentric brother of a relatively little known Labour MP - now of course rather better known for his anti-lockdown protests brother of an extremely well known ex-Labour MP). Even better though the first link that came up (https://amp.smh.com.au/environment/we...) was written by a then Mayor of London now known for his lack of compliance with his own laws.
October 17, 2017
If you want to know all the things we know or guess about the sun, this is definitely the book for you. Lucie Green isn’t just a science communicator — she’s actually doing the research, so she knows what the current questions are, what the latest research is, and all the history of how we came to know what we know. Her enthusiasm is plain throughout, and she does a good job of describing both the actual physical events of the sun, and the sensation of observing and understanding them.
If you’re not hugely into physics, you might find that a few chapters do start to drag. But for the most part, it’s a fascinating book — and there’s a lot of stuff I didn’t know.
Reviewed for The Bibliophibian.
If you’re not hugely into physics, you might find that a few chapters do start to drag. But for the most part, it’s a fascinating book — and there’s a lot of stuff I didn’t know.
Reviewed for The Bibliophibian.
March 27, 2017
Want to Know your Sun - Read this book, you won't find anything better
This book covers every aspect of knowledge/information about the Sun. From the first tentative steps taken by humans to fathom it's own star to the details of inner workings and the tremendous reach of the solar atmosphere has been covered in easy conversational style. The description of difficult concepts like magnetic field reconnection have been deftly handled using easy to understand analogies.
The tale has many a personal touches and the author has been able to communicate her enthusiasm for this very specialised subject strongly.
It is probably the only non-academic book dealing exclusively with the Sun. A must read for everybody interested in science writings and the state of knowledge about solar physics.
However, this book shouldn't be read on b/w ebook reader. Lots of details are lost without colour. I'd to switch to my android tablet from Kindle paperwhite midway.
This book covers every aspect of knowledge/information about the Sun. From the first tentative steps taken by humans to fathom it's own star to the details of inner workings and the tremendous reach of the solar atmosphere has been covered in easy conversational style. The description of difficult concepts like magnetic field reconnection have been deftly handled using easy to understand analogies.
The tale has many a personal touches and the author has been able to communicate her enthusiasm for this very specialised subject strongly.
It is probably the only non-academic book dealing exclusively with the Sun. A must read for everybody interested in science writings and the state of knowledge about solar physics.
However, this book shouldn't be read on b/w ebook reader. Lots of details are lost without colour. I'd to switch to my android tablet from Kindle paperwhite midway.
March 8, 2022
I would like to apologise to Professor Lucie Green for how long it took me to read this book but unfortunately horizon forbidden west came out whilst I was reading it and I got very distracted.
I really enjoyed this book, I think it’s accessible enough for those with a genuine interest in solar physics but definitely will put off a filthy casual. The physics in this book is extremely heavy but it was explained well and with personal passion from the author which is why I enjoyed it so much.
I wouldn’t recommend this book to Lucy as she said to me “I couldn’t imagine reading a book like that for fun.” She’s obviously a filthy casual.
I really enjoyed this book, I think it’s accessible enough for those with a genuine interest in solar physics but definitely will put off a filthy casual. The physics in this book is extremely heavy but it was explained well and with personal passion from the author which is why I enjoyed it so much.
I wouldn’t recommend this book to Lucy as she said to me “I couldn’t imagine reading a book like that for fun.” She’s obviously a filthy casual.
January 9, 2025
Am I biased as I study the Sun? Possibly...
But is this book good? Amazingly good!
Lucie's love of the Sun shines through each page and it's absolutely infecting!
But is this book good? Amazingly good!
Lucie's love of the Sun shines through each page and it's absolutely infecting!
November 27, 2022
Il nostro Sole in realtà non è niente di che, è una stella abbastanza piccola, vive in periferia e nn è certo l'unica ad avere coinquilini planetari.
Eppure è speciale perché ha permesso alla vita di svilupparsi su un pianetino distante il giusto da permettere di mantere l'acqua allo stato liquido.
Alla Terra(non a noi) spettano ancora altri 4 miliardi di anni di relativa serenità prima che la nostra stella esaurisca il combustibile, collassi e schiatti diventando una nana bianca.
Uno dei motivi della nostra esistenza è proprio la massa del Sole. Più una stella è grande più vive (relativamente) poco. La Terra ha impiegato circa un miliardo di anni per partorire dei microbi mentre una stella molto grande può morire in pochi milioni di anni! Capite il problema? Fare la vita è una roba complicata.
La prima cosa che traspare da questo libro è l'amore smisurato dell'autrice verso questa palletta di plasma surriscaldato che è la nostra stella madre.
Lucie Green è una fisica solare e qui ha cercato di spiegare, a gente che fisica non è, com'è fatto il Sole.
Ammetto che in alcuni momenti ho faticato a starle dietro però capisco che nn deve essere stato facile trovare il modo di parlare di cose complicate senza scendere troppo nel dettaglio.
Si racconta anche la storia della fisica solare e di come si è arrivati alle conoscenze attuali.
All'inzio si credeva fosse pieno di carbone, ad esempio.
Nn so quanto sia indicato per tutti, perché alcune parti potrebbero annoiare. Una cosa che avrei gradito e che manca è la foto della sezione del Sole che credo l'autrice abbia dato per scontato ma che a me avrebbe aiutato ad avere una visione d'insieme da cui partire per approfondire le singole parti ma ci sta, forse era troppo elementare.
Quello che viene fuori è sicuramente l' elenco di ipotesi sbagliate sul Sole.
Ed è questo il bello della scienza .
È fatta per lo più di errori ma la cosa meravigliosa è che si impara da questi. Si prova a dare risposte a delle domande. E più si risponde e più ne vengono fuori altre.
Poi qualcuno intuisce e prova che alcune risposte erano sbagliate o incomplete e condivide. E via così.
Ed è meraviglioso
Eppure è speciale perché ha permesso alla vita di svilupparsi su un pianetino distante il giusto da permettere di mantere l'acqua allo stato liquido.
Alla Terra(non a noi) spettano ancora altri 4 miliardi di anni di relativa serenità prima che la nostra stella esaurisca il combustibile, collassi e schiatti diventando una nana bianca.
Uno dei motivi della nostra esistenza è proprio la massa del Sole. Più una stella è grande più vive (relativamente) poco. La Terra ha impiegato circa un miliardo di anni per partorire dei microbi mentre una stella molto grande può morire in pochi milioni di anni! Capite il problema? Fare la vita è una roba complicata.
La prima cosa che traspare da questo libro è l'amore smisurato dell'autrice verso questa palletta di plasma surriscaldato che è la nostra stella madre.
Lucie Green è una fisica solare e qui ha cercato di spiegare, a gente che fisica non è, com'è fatto il Sole.
Ammetto che in alcuni momenti ho faticato a starle dietro però capisco che nn deve essere stato facile trovare il modo di parlare di cose complicate senza scendere troppo nel dettaglio.
Si racconta anche la storia della fisica solare e di come si è arrivati alle conoscenze attuali.
All'inzio si credeva fosse pieno di carbone, ad esempio.
Nn so quanto sia indicato per tutti, perché alcune parti potrebbero annoiare. Una cosa che avrei gradito e che manca è la foto della sezione del Sole che credo l'autrice abbia dato per scontato ma che a me avrebbe aiutato ad avere una visione d'insieme da cui partire per approfondire le singole parti ma ci sta, forse era troppo elementare.
Quello che viene fuori è sicuramente l' elenco di ipotesi sbagliate sul Sole.
Ed è questo il bello della scienza .
È fatta per lo più di errori ma la cosa meravigliosa è che si impara da questi. Si prova a dare risposte a delle domande. E più si risponde e più ne vengono fuori altre.
Poi qualcuno intuisce e prova che alcune risposte erano sbagliate o incomplete e condivide. E via così.
Ed è meraviglioso
May 5, 2025
Professor Green’s book about our closet star is a very interesting and well researched book. I really enjoyed being able to learn more about the history of our observations of the sun and how we know what is happening within.
I’m going to be honest, I did find this book a struggle to read, but that was because I was having to re-read sections as I would get confused about what was said, might be my own dyslexia though.
Would definitely recommend it if you’re interested in solar physics, or want to know more about the star we call the Sun.
I’m going to be honest, I did find this book a struggle to read, but that was because I was having to re-read sections as I would get confused about what was said, might be my own dyslexia though.
Would definitely recommend it if you’re interested in solar physics, or want to know more about the star we call the Sun.
January 25, 2020
There is a lot to learn about our Star. This book provides an amazing insight for our Sun. Highly recommended for everyone who evolved and constantly get nourishing from the prime source of all the form energy on this planet.
July 5, 2017
'15 Million Degrees' is a cool book on a red hot subject. As an amateur astronomer with a large computer controlled astro scope, Lucie Green's book has inspired me to utilise my optics to view our star in hydrogen alpha wavelengths. Living on the misty twisty moors of northern England where the night sky is often obscured by clouds, turning my observing to day time may well be productive.
For the casual reader who wishes to take Lucie's 'journey to the centre of the sun' I'm sure that they will not be totally blinded by science. Admittedly there are sections of this book that cover magnetic helicity and flux ropes that I had to take in small bites, but generally for all things solar this book provides a fully comprehensive, fact packed, and intelligently explained up to date study of the complex dynamics of our sun.
For the casual reader who wishes to take Lucie's 'journey to the centre of the sun' I'm sure that they will not be totally blinded by science. Admittedly there are sections of this book that cover magnetic helicity and flux ropes that I had to take in small bites, but generally for all things solar this book provides a fully comprehensive, fact packed, and intelligently explained up to date study of the complex dynamics of our sun.
March 5, 2018
Isn't the sun just fascinating? We only exist on this planet because we happen to be the perfect distance away from the sun. I've never really known vast amounts about our star, but I do now. Green's book can be hard to follow at times simply because the things she's describing are so difficult to visualise and comprehend that it fails to make sense. However, this book is well written enough that after rereading some chapters several times, I finally got there and I feel I can understand a bit of Green's love for the sun. I can certainly see why someone might devote their entire career to trying to unlock its secrets. Definitely a book worth persevering through!
July 16, 2019
Our whole world literally revolves around it. Many religions have worshiped it, probably for 10's of thousands of years. Any inquiring mind must at some point have wondered how it works, surely?
This book delves into the mysteries of our solar system's chief source of power. A great overview of the topic for those inquiring minds that wanted to scratch the surface a little.
You don't need a knowledge of plasma physics or magnetic interactions. But, it is pitched at a level where those ideas are just out of reach. Thoroughly recommended for any general interest science reader or anyone with an early interest in astronomy or astrophysics.
This book delves into the mysteries of our solar system's chief source of power. A great overview of the topic for those inquiring minds that wanted to scratch the surface a little.
You don't need a knowledge of plasma physics or magnetic interactions. But, it is pitched at a level where those ideas are just out of reach. Thoroughly recommended for any general interest science reader or anyone with an early interest in astronomy or astrophysics.
June 7, 2021
Sommige stukken waren voor mij wat moeilijk om te volgen toch denk ik dat het zo eenvoudig mogelijk beschreven werd ik mis wat chemische en natuurkundige kennis om het boek helemaal te volgen , wel interessant beschreven door een schrijfster waarvan je voelt dat ze razend enthousiast is over haar werk ( en terecht)
Het doet mij denken om wat meer te lezen over aard (of zon) magnetische velden , het lijkt mij interessant, zou een aardmagnetisch veld verband houden met temperaturen , en zouden de mensen mogen prutsen aan het aardmagnetisch veld ( als ze er genoeg informatie over hebben )
Het doet mij denken om wat meer te lezen over aard (of zon) magnetische velden , het lijkt mij interessant, zou een aardmagnetisch veld verband houden met temperaturen , en zouden de mensen mogen prutsen aan het aardmagnetisch veld ( als ze er genoeg informatie over hebben )
January 29, 2023
Really enjoyed it. Favorite chapters were on sunspots, solar flares, and CMEs. Could have used a few more images, maybe one on the various layers, but not a real problem. Took me some time to get through some of the explanations because I don't have the physics or astronomy background, but with a basic understand of gravity, centrifugal force, elements, atoms, molecules, and the solar system I was able to get through it. More than just a description of the Sun and its processes, it's also a history of how the astrophysicists got to know what they know.
November 18, 2017
An entertaining and informative read. I found the tone a bit too light overall, although, conversely, the sections where the author gets into details of how the magnetic field of the sun works were difficult. For me, I'd have liked a bit more on the fusion processes, especially on how these are expected to progress through the later stages of the sun's life.
August 19, 2021
This is a fantastic information dense book. Not for the faint hearted, but if the title interests you then the author’s entertaining and informative prose on the history of the science of the sun and the science itself will keep you mesmerised! Highly recommended, although of course (physics not being my forte) some of it went over my head. I am no passing the book on the my space crazy nephew.
December 1, 2021
Every question you ever had about the sun answered and then some! Prof Green is clearly very passionate about her work and it's infectious, I devoured this book in a few days because every bit I read just made me want to read more. It's written in a way that makes it very easy to digest, and it gave me a few new things to google which is always good. Highly recommend!
September 5, 2023
Well the book has to go back to the library so I have bought myself a copy as I know I need to have it around to read again and lend to friends. It was fabulous - not just the most up to date discoveries and theories but also history and lots of science - and a great read. I learned a lot. I had no idea we knew so much or how complicated and so much more to find out.
May 30, 2017
This was a really interesting and accessible guide to the Sun and its workings. I've found the clear scientific explanations to be a really helpful complement to my undergraduate astronomy course. Green also weaves in the history of discoveries about the Sun.
June 1, 2018
Pretty good - especially if you like magnetism! :)
The full story of the sun, and all it's bits told in a nice easy way. I spotted a couple of minor errors, but nothing too upsetting, and I bet no one else would spot them.
The full story of the sun, and all it's bits told in a nice easy way. I spotted a couple of minor errors, but nothing too upsetting, and I bet no one else would spot them.
September 8, 2020
I enjoyed this book. Lucy's writing style is easy to read. She managed to discuss complex topics in an informative simple way. I liked the number of useful diagrams. The book meandered over many topics relating to the Sun and gave good insight into how science is done.
Well worth a read
Well worth a read
April 29, 2018
Very well written, and interesting. It does what it says on the cover. It is about the sun, and the history of our understanding of it.
May 30, 2019
Very well written with a style that is as bright as the subject itself. I like the stories that Lucie Green uses to reveal the science behind our star.
August 18, 2019
What a superb book, I couldn’t put it down and feel a little sad that I’ve now finished it. It’s everything you ever wanted to know about the sun but never dared ask.
November 5, 2023
Excellent review of solar physics and phenomenon. Well written and engaging.
March 2, 2025
Brilliantly weaves complex scientific theory and practice together with stories to help explain how the sun ‘works’.
November 22, 2025
Gli argomenti sono molto interessanti, però da metà in poi mi sono un po perso. Avrei gradito qualche foto in più
August 21, 2021
I used to think that the Sun is one boring large ball of hydrogen with nuclear fusion going inside it. But this book shows that Sun is indeed a very dynamic and interesting celestial object to study with so many mind boggling things going inside it.
Sun is our best bet to understand what happens inside the stars, and this book does an excellent job in helping layman understand these concepts.
Sun is our best bet to understand what happens inside the stars, and this book does an excellent job in helping layman understand these concepts.
September 23, 2016
Ever since I pointed my telescope at the Sun, projecting an image onto a piece of paper and saw the sunspots for myself - they were actually there! - I have always been fascinated by the star that gave us life. I have seen documentaries that showed blazing flares, coronal mass ejections, images taken using different frequency ‘light’, effects on Earth's magnetic field, which were all fascinating, but they did not fully explain what was really going on inside the Sun to cause all these effects.
Professor Lucie Green's '15 Million Degrees' finally answered all my questions, and much more. I read the book in one session, which took me late into the night, but it was worth the trip. Professor Green has a writing style that is easy to read, yet she is able to impart highly technical information that is readily understood - the reader does need at least an entry level university education in nuclear physics, chemistry and astronomy to absorb everything.
The book smoothly traces the history of astronomy and Solar observation, development of quantum theory and understanding of the atom, which over time helped scientists understand what the Sun was, what powers it, and its behavior. Professor Green sprinkles her work with fascinating snippets of research done over the last 150 years and eureka moments that has led to our understanding of not only our own star, but stars throughout the universe. When it came to explaining some tough processes that go on inside the Sun - how light escapes, what are sunspots, flares, threats to Earth - Professor Green tackled these with skill without resorting to highly technical explanations. The book left me with a much deeper understanding of our Sun, the journey immensely satisfying and rewarding.
Professor Lucie Green's '15 Million Degrees' finally answered all my questions, and much more. I read the book in one session, which took me late into the night, but it was worth the trip. Professor Green has a writing style that is easy to read, yet she is able to impart highly technical information that is readily understood - the reader does need at least an entry level university education in nuclear physics, chemistry and astronomy to absorb everything.
The book smoothly traces the history of astronomy and Solar observation, development of quantum theory and understanding of the atom, which over time helped scientists understand what the Sun was, what powers it, and its behavior. Professor Green sprinkles her work with fascinating snippets of research done over the last 150 years and eureka moments that has led to our understanding of not only our own star, but stars throughout the universe. When it came to explaining some tough processes that go on inside the Sun - how light escapes, what are sunspots, flares, threats to Earth - Professor Green tackled these with skill without resorting to highly technical explanations. The book left me with a much deeper understanding of our Sun, the journey immensely satisfying and rewarding.
February 19, 2017
In the end I found this book becoming too full of 'what I did next', and it began to feel less of a popular science approach than a piece of self-publicity. A shame, because the early chapters were clear and useful.
Displaying 1 - 30 of 36 reviews