Review: "Stellar Spectral Classification" by Gray & Corbally

[madbadgalaxyman]

Here is my quick Book Review of Gray and Corbally, from my recent science forum thread on Stellar Evolution books:

"Stellar Spectral Classification", 2009, by Richard O. Gray and Christopher J. Corbally, Princeton Series in Astrophysics, Princeton University Press, ISBN 9780691125114

This book is literally "The Bible" of stellar spectra and stellar spectral classification. This massive and comprehensive and scholarly work is an essential reference for all optical and near-infrared astronomers. This book explains the current iteration of the standard MK System of Classification of the spectra of stars, and it contains a comprehensive collection of stellar spectra , with detailed explanatory information on the many stellar types, including spectra and explanations of most of the recently-discovered stellar and sub-stellar types (e.g. the L & T dwarf classes, and brown dwarfs). Extreme and rare stars like O2/O3 stars and Wolf-Rayets and LBVs get a much greater coverage than in earlier references, reflecting today's greater knowledge of these "superstars". This work somewhat resembles a supercharged and super-extended version of Kaler's popular-level book on Stellar Spectra.....and it is much more up-to-date! Because the Spectral Classification of Stars does not have to involve lots of hairy physics and mathematics, this is an area of professional astronomy in which amateur astronomers can become highly competent.

Reviewer's note:
This is not intended to be a comprehensive review. But it does describe the book accurately.

[Merlin66]

+1 from me!!

[madbadgalaxyman]

Thanks for the review of my review, Mr Merlin,

By way of further explanation, I note that I am not anywhere near to being an expert reviewer when it comes to stellar spectra, so I couldn't comment on subtle aspects of the authors' arguments (.....I mainly look at things at the level of Galaxies).
However, I am quite qualified to review this book, as I have a "pretty heavy astro-background"...... I have been a regular reader of the AJ, ApJ, etc., for a couple of decades.

What I can say is that I enjoyed and understood the exposition, as it is clearly written and does not overdo the physics/maths angle.

As this book is focused squarely on the observables instead of on complex mathematical/physical arguments, this book would seem ideal for the "lesser brethren" who are not professional astrophysicists;

- amateur spectroscopists
- advanced amateur astronomers who are accustomed to reading the more 'technical' (that is, physical/mathematical, with a readership level well above popular-level) material on stars & clusters
- non-professional astronomers who are inclined towards physics and mathematics and/or "complex technical material"

cheers,
madbadgalaxyman

[madbadgalaxyman]

Here is a (legally accessible) sample chapter from the book:

http://press.princeton.edu/chapters/s8963.pdf

What this extract from the book illustrates is how very well Gray and Corbally write, and it is, in itself, a very valuable 27 Page Essay on the history of spectral classification.

If you need more information about the contents, the style, and the readership level, you can also access some of this book at Google Books:

http://books.google.com.au/books?id=S_Sh1i226wwC&printsec=frontcover&dq=stellar+spectral+classification&hl=en&sa=X&ved=0ahUKEwiytaGAnd7LAhWJkpQKHYm0DW UQ6AEIHDAA#v=onepage&q=stellar%20spectral%20classificati on&f=false

[Merlin66]

Richard,
It's an interesting experience to compare the sample spectra from Richard Walker's excellent Spectra Atlas ( http://www.ursusmajor.ch/astrospektroskopie/richard-walkers-page/index.html ) - down the bottom rhs.
with the detailed spectra in Gray&Corbally....

The next step up the learning curve is the challenging:
"The Observation and Analysis of Stellar Photospheres" by David F Gray.
This covers the modelling aspects of stellar atmospheres and the impact/ effects of temperature, velocities, chemical composition etc. etc.
Onwards and Upwards.

[Glenpiper]

While the Gray & Corbally tome is an excellent reference ... in fact the ultimate one ... it is expensive and maybe overkill for most amateurs ... while I have the G&C book I usually go to Gray's "A Digital Spectral Classification Atlas" first as it generally has all the info I need. A pretty good synopsis of the G&C book as zero cost. Download at http://www.aesesas.com/mediapool/142/1423849/data/DOCUMENTOS/digitalspectralatlasGray.pdf

[madbadgalaxyman]

G'day there, Bernard,

You are right that I haven't really accurately defined the 'readership level' for which this book is intended. I am working on a somewhat longer review for amazon.com, which will deal with the sort of person this book is suitable for.

But you would be surprised how 'heavy' some amateurs get.......there are amateur astronomers out there doing the most extraordinary things, activities that in fact do require Extremely Detailed Knowledge at a Very High readership-level similar to that of Gray and Corbally.

Indeed, this text is emphatically not overkill for some amateurs.....
to give one example, in the Galactic and Extragalactic Research area, there are people like me, and Dennis Webb (in the united states), who have spent hours poring over galaxy data, every day for many years.....and we are 'humble amateurs', doing it just for fun.
(for instance, I can classify galaxies as well as any professional astronomer does)
There must be some who take Stellar and Star Cluster astronomy equally seriously.....
for instance our very own Dana (in IIS) (= Weltevreden SA) seems to spend all of his time reading scientific papers about stars and star clusters, yet he is not a professional astronomer....so he wouldn't find this book difficult or too detailed.

And you call this book expensive?
I guess 'expensive' is a relative term, when you consider that my own personal library of astronomy books is well better than that of many Australian University libraries, in terms of containing reference works suitable for supporting extragalactic research.....
(not to speak of my biology books collection, which is similarly extensive!)

Many amateurs spend a fortune on equipment, but resist spending a large amount on books. I would rather have the books.

cheers,
madbadgalaxyman,
alias Robert Lang

[Glenpiper]

Hi Robert,

I think you misunderstand the point I was trying to make .. that for most amateurs the free downloadable Gray classification atlas probably contains sufficient information for MK classification. Gray himself says it is synopsis of the 600 page G&C book. Compared to having to pay ~AUD100 for G&C I consider 'free' a great bargain if it does the job.

I doubt I would be surprised at what advanced amateurs are capable of, having just returned from this weekend's NACAA Conference at Sydney university where advanced papers were presented. I also made a presentation there showing the professional quality spectroscopy SASER amateurs do for pros worldwide (you can see our work at http://saser.wholemeal.co.nz/). A paper that used a lot of our spectra was published by ApJ in January (http://arxiv.org/abs/1601.03396) ... I'm the third listed author. Ken (Merlin66) is also a SASER member, so I think we do have some understanding of amateur spectroscopy and stellar classification.

[madbadgalaxyman]

Congratulations!

Excellent work.

And if you are from an amateur astronomical background, then quadruple praise for your excellent work.

I well recognize how difficult it is for most amateur astronomers to achieve the expertise necessary to undertake peer-reviewed research, and to "keep working at it for a prolonged period", given the inevitable constant non-astronomical distractions that amateurs typically have to endure.

Best Regards,
Robert

I have not been to NACAA for many many years. Perhaps I would find it a lot more interesting than I used to in the 1990s, given that the best amateur workers seem to be doing much more interesting and significant work, these days.

[Glenpiper]

Hi Robert,

I think you would find that the quality of NACAA papers has improved, mainly because modern technology (hardware and software) is more readily available at a reasonable cost, giving us amateurs access to better tools for serious work.

[madbadgalaxyman]

Here is the text of my more extensive review, which will be published at amazon.com
___________________________

This massive and scholarly work is a very important resource for all optical and infrared astronomers, so comprehensive that is virtually "the Bible" when it comes to the spectra of stars and stellar spectral classification, and guaranteed to remain the essential single-volume reference on stellar spectra for many years to come. This book fully explains the current version of the standard MK System of Classification of the spectra of stars, a system that has continued to evolve and gain more breadth and sophistication over the decades.

This book contains a comprehensive collection of stellar spectra, illustrating virtually all of the many and varied types of stars, and explaining how to classify their spectra, with detailed explanatory information about the many types of stars, including spectra and explanations of most of the recently-discovered stellar and sub-stellar types; such as the the L & T dwarf classes, and the brown dwarfs. Extreme and rare types of stars, such as O2/O3 stars and Wolf-Rayets and LBVs , get a much greater coverage than in earlier references, reflecting today's greater knowledge of these "superstars". The up-to-date nature of this work is further illustrated by the inclusion of substantial numbers of spectra in the ultraviolet and infrared wavelength-regimes.

While this text is intended for professional astronomers, and for Upper-Undergraduate to Graduate level students of physics and astronomy, it will also be extremely useful for:
- astronomers and physicists and other practising scientists wishing to achieve expert knowledge in stellar astronomy
- advanced-level amateur spectroscopists
- "Very Diligent and Determined" non-professional astronomers with the ability to understand "large amounts of complex technical material" incorporating some physics.

However, I warn that this book is likely to be too detailed and technical for the average amateur astronomer.

Advanced-level amateur astronomers will be able to benefit from this reference work, if:
- they are accustomed to reading extensive material which incorporates a physical/mathematical approach to the subject matter, the sort of reader that can tolerate books which are essentially designed for upper-level undergraduates in the physical sciences
- they have a solid background that includes habitually reading astronomy resources with an intended readership-level that is well above the "popular-level descriptive introductions"

In summary, this text is well-structured and very clearly written , so it can be understood without struggle by its intended readership. I found this to be an enjoyable and enlightening read about the intricate subject of the observed properties of the many and varied types of stars. In passing, I note that many amateur astronomers could potentially achieve a sophisticated knowledge of the spectra of stars, as it is possible to become conversant with classification systems - such as spectral classification - without the necessity for lots of hairy physics and mathematics.