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| View Larger Image | Exploring the Secrets of the Aurora (Astrophysics and Space Science Library)
by Syun-Ichi Akasofu
| | List Price: | $59.95 |  | | Available: | Usually ships in 24 hours | | | | | Sales Rank: | 1876139 | | Studio: | Springer | | | Binding: | Paperback | | Number Of Pages: | 288 | | Publication Date: | July 31, 2007 | | Publisher: | Springer |
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Product Description
Prominent progress in science is inevitably associated with controversies. Thus, young researchers, in particular, have to learn how to persevere during the period of controversy and struggle for acceptance. Unfortunately, the skills needed are not taught in textbooks or monographs, which mostly describe the consensus of contemporary experts. This book, which is based on my own experiences as a scientist, describes the history of the progress made in auroral science and magnetospheric physics by providing examples of ideas, controversies, struggles, acceptance, and success in some instances. Although no general methodology (if any exists) is mentioned, I hope that the reader will learn about the history of progress in auroral science and examples (right or wrong) of dealing with the controversies. |
CUSTOMER REVIEWS (Average Customer Rating: 5.0 based on 1 review)
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An excellent book about auroral science 
The Aurora offers us plenty of scientific data to explain. This wonderful book (which includes four beautiful full-color photos of the aurora) describes the experiences of the author, a great auroral scientist, in characterizing and explaining auroral phenomena.
Akasofu begins his story in 1860. In that year, R. C. Carrington observed an intense white light solar flare. About 16 hours later, a brilliant auroral display appeared over northern Europe and elsewhere. In the same year, E. Loomis showed that the aurora tends to appear along a fairly narrow belt centered around the northwest tip of Greenland.
In 1896, Kristen Birkeland proposed that auroras were caused by "cathode rays" (electrons) emitted by the Sun and guided towards the Earth's higher latitudes by the Earth's magnetic field. And in 1931, Sydney Chapman and Vincenzo Ferraro came up with the idea "of confinement of the Earth's magnetic field in a cavity carved in the solar gas flow."
Akasofu then tells of his own contributions to the field. In 1958, he went to the University of Alaska to study with Chapman. He noticed at once that the aurora "tends to appear in the northern sky in the evening, advances toward the zenith (or even the southern sky) of Fairbanks (gm lat 64.6 degrees), and recedes towards the northern sky in the morning." This shift had been well-known for at least two decades (and perhaps many millennia). But it was a "great surprise" for Akasofu that the aurora behaved this way in Fort Yukon too. And at Barrow. Auroral data from Siberia then led Akasofu to realize "that when an auroral arc is quiet in Alaska (in the midnight sky) it is also quiet over Siberia (in the evening sky), and in Canada (in the morning sky)." He then showed that during magnetic disturbances, the auroral ovals expand in area, with the equatorward auroral zone boundary moving to lower latitudes. From this he evolved the concept of a magnetospheric substorm. The auroral manifestation of this is the auroral substorm, the basic geomagnetic phenomenon associated with auroral activity.
The author covers a variety of topics associated with the aurora. One is about the Earth's dipole. Akasofu asks if it is really off-centered and inclined. Or is there a main dipole which is aligned with respect to the rotation axis and a few other dipoles at the surface of the Earth's core?
Another chapter is called the "myth of the emerging flux tubes." Sometimes we see pairs of sunspots. Flux tubes are one hypothesis that may explain them. But this is just a hypothesis. It requires more verification to be more than that.
Yet another interesting and useful chapter is on predicting geomagnetic storms from solar observations.
The author even suggests exploring for life on extraterrestrial planets by searching for oxygen emissions (the 557.7 nm "green line") in their aurora.
I was intrigued by Akasofu's thoughts about doing science. Auroral phenomena have plenty of patterns to them. However, no theory about them can explain all the data. As in other areas of science, researchers have too often tried to force their data to fit into some existing hypothesis. Unfortunately, some of the data are counterintuitive and simply don't fit. Besides, the phenomena are not exactly repeatable. As Akasofu says, "no two substorms are alike."
Akasofu tells us that a scientist must choose which observed facts are to be considered essential. Then one tries to derive a theory which explains these essential facts. It isn't easy, and one must keep an open mind. From what I have seen of auroral data, I have to agree.
I think all scientists, not just auroral scientists, could profit from reading this book.
March 08, 2005 | |
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