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I dont profess to understand half of what was wsritten in this very well presented book True tales with lovely photographs dr Melanie Windridges tale of her quest to see the Northern lights well written and presented, a good read. Fascinated by the mysterious shape shifting of the Northern Lights which intrigued both local communities and explorers long before they had an inkling of the scientific causes, plasma physicist Melanie Windridge set out to write a popular science cum travelogue to explain the phenomenon, visiting Sweden, Norway, Iceland, Canada and Scotland in the process.The author makes comparisons to twanging elastic bands, strings of pearls or games of cricket to make theories easier to grasp There is also a good deal of repetition, which can be useful, although I was left confused and frustrated by the fragmented explanation with often unclear diagrams of the all important Dungey Cycle by which the plasma stream of negatively charged particles from the solar wind interact with the earth s magnetic field to give some of the most spectacular aurora effects on the night side of the earth Perhaps I am puzzled over the above because the process is still not fully understood by the experts.No doubt to achieve a reasonable length and to make the physics digestible, the text sometimes seems padded out with mundane details of encounters, or over long digressions into, say, the history of photography, but one cannot afford to skip anything I found my interest unexpectedly caught by, for instance, the history of the Canadian town of Yellowknife, named after the copper blades of the knives carried by the local Dene people In the series of prospecting rushes for minerals, the town had a belated gold mine open right up to 2003 For decades, the economy has functioned with ice roads , literally cleared of snow in order to freeze hard enough to support convoys of lorries, Now that the Canadian government is committed to the construction of the Mackenzie Valley Highway, there is local ambivalence over the inevitable damage to the ecosystem and traditional culture, the price to be paid for access to commercial progress The focus on Yellowknife is of course due to its proximity to the Arctic Circle where the Northern Lights are most visible at night in the winter months.Even if I am left unclear over the aurora oval and reconnection , I have certainly learned a good deal Seen with the naked eye, the aurora may be much less impressive than the effect to be captured for the same event with a camera Varying between arcs and patchy pulsations , the familiar green of the aurora derives from oxygen electrons which, with lower energy, may appear red nitrogen molecules emit blue, violet and pink colours Those who lived through the hundred year period from 1620 which became known as the Maunder Minimum would have seen few auroral displays, which seemed to coincide with a lack of sunspots visible on the surface of the sun A coronal mass ejection or vast blob of plasma may be launched from the sun into space at great speed Organisations like Swipsie , the Space Weather Prediction Center are co operating to invest increasing resources in predicting whether it is likely to interact with the solar wind ahead of it because this can twist up the magnetic fields and lead to a severe event on earth apart from interference with the operation of satellites, this could involve damaging an electricity grid, or an unusually large and dramatic auroral display. The Beautiful Aurorae, Or Northern Lights, Are The Stuff Of Legends The Ancient Stories Of The Sami People Warn That If You Mock The Lights They Will Seize You, And Their Mythical Appeal Continues To Capture The Hearts And Imagination Of People Across The GlobeAurora Explores The Visual Beauty, Ancient Myths And Science Of The Northern Lights And Challenges The Popular Theory Of How The Lights Are Formed Plasma Physicist Melanie Windridge Explains This Extraordinary And Evocative Phenomenon, A Scientific Marvel Unlike Any Other In Which The Powers Of Astronomy, Geology, Magnetism And Atomic Physics Combine To Create One Of The Wonders Of The Natural WorldAs Melanie Travels In Search Of The Perfect Aurora, She Uncovers The Scientific Realities Of This Plasmic Phenomenon Full Of Natural Power She Combines The Science Behind The Lights With A Fascinating Travelogue As She Pursues The Aurora Across The Northern Hemisphere From The Arctic Circle To Scotland An interesting mix between travelogue, history lesson and scientific explanation I enjoyed the historical parts the most because I found it fascinating to find out about the beginnings of auroral research and the explorers who were enthralled by the lights The scientific explanations were complex, but the author tried to make them understandable for non physicists like myself I feel like I got most of it even though some details may have escaped my understanding I found the explanations regarding the aurora a lot interesting than the parts about space weather, its influence on electricity, and the different eclipses But that is simply a personal preference Overall, it was an interesting read, although it takes some time to get through. Windbridge describes her journeys through various countries in search of the aurora, using her travels as a lead in to much information on it An excellent read with good balance between the travelogue and the science.Her travels in Sweden and Norway provide an introduction to life in the cold north, including the use of skis, dog sleds and snowmobiles The tales and views of the aurora held by the indigenous people were often those of fear Due to it s proximity to the aurora, Norway was the center of much early scientific work on the aurora Most notably, Kristian Birkeland showed that it was due to particles from the sun which he modeled with his device, the terrella.The author uses her visit to Iceland as a springboard into the physics were she provides a very understandable overview of the mechanisms in the earth s core that generate the magnetic field the idea of plasma as the fourth state of matter where the atoms are ionized the fusion in the sun releasing photons from the photosphere which features the variable sunspots and the corona made up of high pressure plasma expanding into space as the solar wind, forming the heliosphere.Due to the tilt of the earth s geomagnetic axis about ten degrees , the auroral zone 60 75 degrees magnetic latitude is also tilted As such, the aurora is visible in Scandinavia, difficult to see at all in Russia, but is visible at lower latitudes in Canada Canada s east west size means it has prime aurora viewing area than any other country.The Dungey Cycle proposes that the aurora is driven by magnetic field reconnection in the magnetosphere Newly closed field lines contract back toward earth, catapulting particles down toward earth The most impressive auroras form when the magnetic field of the solar wind is directed south, opposite the earth s field The Solar Wind Clock Angle and the Cross Polar Cap Potential are indicative of expected auroral activity The AuroraMAX project, run by volunteers, is an outreach group which also manages a number of cameras, including a webcam Early photography examined the spectral lines associated with the aurora Confusion occurred as some of the spectral lines are forbidden , only being seen in plasmas Eventually it became clear that the green color came from oxygen red above 200 km, but green down to 150 km, while the blue, violet and magenta are due to nitrogen below 100 km When the aurora is seen to the south, color is seen, while further north the it appears largely green Geomagnetic storms enhance the auroras, but there is much about the physics that remains unknown.Auroral activity relates to the number of sunspots Solar activity increases the number of cosmic rays, creating carbon 14 Thus a record of solar activity is imprinted in trees, showing a reduction in the aurora from the mid fifteenth century to the mid sixteenth century Deduced greater activity in the twelve and thirteenth centuries is supported by a jump in observations in historical records.The Sun s effects on the near Earth environment are known as space weather, comprising solar flares, radiation storms and geomagnetic storms While not generally noticed, large events can be massively disruptive to human activities These storms can interfere with aircraft movements, GPS location and power systems Solar storms are categorized with a K index planetary effects are given a Kp index and a G index by NOAA These indicies can be used to gauge likely aurora activity. I read Aurora while on a two week cruise around Iceland, Norway, and Scotland, and it made for perfect holiday reading it was about a journey, and in the same part of the world as I was exploring although, obviously, I didn t see the Northern Lights since I visited in the summer , and it was just the right amount of challenging I often prefer reading non fiction books on holiday.This book is a wonderful mix of autobiography, science, and travel, and the structuring of the book around Windridge s journey works particularly well in making Aurora coherent But most impressive is Windridge s ability to make complicated science intelligable and interesting, especially through everyday comparisons, which she seems to have a particular knack for.A highly readable book about a fascinating phenomenon, Aurora is definitely one I would recommend if you re interested in learning about the Northern Lights. I am obsessed with Nordic countries, Winter, and the Northern Lights I recently travelled to Iceland but in May, where I had a slim chance of seeing the Aurora The next best thing was Perlan, who provide a magical planetarium experience which explain the science and mystery behind the Aurora and her sisters in the universe I wanted to read this book for these reasons and to discover Melanie s journey across the Arctic Circle in search of the lights I really loved the travelogue parts, which provide insights of various cultures and their own folklore and myths told by their ancestors about the Aurora and what they thought it was meant It truly sounds magical and I need to experience the spirituality that comes with it I am not very scientifically inclined, which resulted in me skipping most of the Forecasting Space Weather chapters I tried, but I didn t really know what was going on it is confusing which didn t make it enjoyable to read Sorry Melanie it s me, not you Overall, I m glad I picked up this book and expanded my knowledge and non fiction choices Fantastic I read some of the reviews of the book first, and am glad I didn t listen I thought the book was very informative from a scientific perspective, and found out what I wanted to know about how and why auroras exist The book also includes inspiring philosophical notions and cultural references about how civilizations have understood auroras throughout the ages. Part science read, part travelogue although definitely heavier on the science side of things , Aurora covers quite comprehensively everything you wanted to know about the subject The author who is herself a physicist specialising in the subject examines multiple aspects of the phenomenon, including its role in history and art, as well as getting to grips with the technical question of how it all works I think it was well explained, speaking as one of those people who is enthused by space science but doesn t have an aptitude for it But, in that contrarian way that the author herself observes, my favourite parts were still the bits where the book waxes lyrical, despite knowing the fascinating science behind it all There s just something quixotic about the aurora that has timeless appeal. This is a blend of travelogue, scientific explanation and cultural and scientific history It is most successful at the travelogue and least successful at the scientific explanation The author unfortunately suffers from the Curse of Knowedge at times whereby understanding gained over many years of hard study becomes second nature and one forgets that even the basics are unfamilar to most people even most well educated people This makes some of the attempts to explain the origins of the aurora somewhat muddled It s worth reading, though, if you are interested in the aurora, polar exploration or how vulnerable much of our technology is to events utterly beyond our control, whose ultimate origin is our sun.