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How stars work
The biggest explosionsWheeler begins his book by describing how stars form, how they evolve in response to gravity, how they ignite, how they burn, and eventually how they die. This is a logical introduction, since virtually all the examples of cosmic catastrophes involve stars in one form or another. Like people, though, the life of each star is unique - and the end times are very different. Wheeler does an excellent job of describing the negative feedback process that stabilizes solar activity. If the star generates too much heat it expands. This expansion reduces the temperature, and throttles back on the rate of nuclear fusion. If the star cools down it contracts, and the contraction heats it up again, keeping the rate of fusion at a remarkably constant level for long periods of time during the stars life.
Much of Wheeler's text is actually about how stars evolve. This is important because to understand their deaths, you need to understand how they are born and how they evolve over their lifetimes. Their deaths are frequently the most interesting parts of the story because they are often involved with the catastrophes that are the book's principal thesis. While I bought the book because of its discussion about cosmic catastrophes, I found it valuable for its descriptions of stellar evolution alone. This includes a nice description of the "solar-neutrino" problem as well as a nice explanation of the red-giant phase, and especially the last stages during the life of a massive star that explodes in a super nova.
The foundational understanding of the basics of stellar evolution makes it easier to follower Wheeler as he takes the reader on a tour of the major players in cosmic catastrophes: white dwarfs, super novae (of many different types), neutron stars, black holes, and gamma-ray bursts. Wheeler's descriptions of these phenomena (to the extent that modern science understands them) are among the best I've seen in a popular science textbook. There is also a smattering of discussion about the origin of the universe in the Big Bang, and some interesting speculation about time (and space) travel using black holes.
In any book dealing with modern cosmology and astronomy there are inevitable discussions about the nature of space and time and how they fit together with Einstein's theory of general relativity. Most such books have at least one figure showing a funnel-shaped construct with grid lines converging as they swoop into the tapering end where the black hole resides. Wheeler uses lots of such diagrams. However, I think he does a better job than most at helping the reader understand what the diagrams illustrate. More importantly, he helps the reader understand what the diagrams do not illustrate, and their limitations (he dispels some common misperceptions about these sorts of figures). I especially enjoyed Wheeler's explanations about how one might (with the application of the appropriate mental acrobatics) use the diagrams to actually envision what is really going on in our multi-dimensional world.
Another thing I liked about Wheeler's book is the clear and frequent illustrations. For the most part the author has anticipated those places where prose just cannot quite complete the mental picture. When this happens there is inevitably a well-constructed diagram that finishes the concept and makes things clear. There was one exception, however. Figure 7.3 really needs to have an arrow or circle marking the location of SN 1987A. [I'm pretty sure I found it, but the exposure changes between the photographs, and so I'm not quite sure. It would have been nice to have the author's help in preventing a false identification.]
Reading this book one gets the sense that even though it is a qualitative description of astronomy (there are no equations) Wheeler is not over simplifying. His discussion of super novae, for example, lists many classes and describes theoretical uncertainties that other authors gloss over or ignore all together. Of course there is much more detail to super novae than what is in Wheeler's book. But at the qualitative level Wheeler leaves the reader understanding that there are many classifications of super novae, that some of the boundaries between classifications are not always so clear cut, and that we still don't know a lot about how some types form, and how other types explode. These are concepts that other popular science textbooks don't always convey. I think the only thing missing from the chapters on super novae is a table that summarizes all the different types and some of their descriptive identifiers.
Unlike some popular science texts, Wheeler devotes quite a bit of time describing the evolution of binary stars, which play an important role in some of the greatest cosmic catastrophes. I think he does an especially good job of qualitatively describing accretion disks, and how they fit in the context of mass transfer in binary systems. It's this mass transfer that is ultimately involved in some of the most spectacular catastrophes in the sky.
Overall, this is a great book. If you enjoy astronomy I'm sure you will find it satisfying and informative. It's just the sort of book to enjoy on a vacation, or after a grueling day at the office.


Cool then, cool now.
A statement of simplicity, that form follows function.Adam Ellwood


The Secret Knowledge of Water by ChildsAnnette Otts Beaverton, Al.
Crossing Paths

e-Learning Work BookCheck- use of the web for learning (whether academic, professional, self-directed, or corporate)
Check- understanding of the key issues.
Now you need a resource showing you how to make it all work effectively, and give you new ideas. This is where Curriculum Webs fits in- whether corporate HR intranet or K12 science projects, or anywhere in-between.
'Curriculum Webs' is clear, well-illustrated and thorough, with lots of examples giving you the confidence to move forward.
Chapters span:
- planning- context, process
- curriculum goals- learners, subject, pre-requisites, rationales
- learning activities- individualizing, grouping, activities
- gathering web resources- bookmarks, searching, evaluation (m, copyright issues
- designing effective websites- audience, information and materials, visual metaphors, navigation, chunking
- laying out web pages- design, white space, colo(u)r, styles, moving, frames/tables
- multimedia
- interactivity
- organizing ands assessing learning
- evaluating and maintaining curriculum webs
-teaching
- teaching teachers- training, standards, organizations
- appendix- servers, clients, browsers, bandwidth, names/URLs, html
Note: steers away from eLearning hype (although misses opportunity for entertaining eLearning anecdotal sidebars!).
Overall, a very worthwhile, vendor neutral, action-focused workbook on practical eLearning.
A unique and wonderful guide for teachers using the web

Definitely worth gettingIn summary, this is a good, practical book you can start using before you're even done reading it.
A very practical guide to improving customer satisfaction

AWESOME!!!
Three Awesome Stories

A brilliant, yet readable teaching on Self-Image/Esteem.
This has the potential to change your life forever.

Refreshing Look at the State of American ChristianityThis book documents that journey as well as puts forward Christian apologetics which is so needed in our pluralistic and postmodern times. I found the separation into tough-minded and tender-minded apologetical approaches helpful and insightful. The Christian Church certainly needs to reclaim and make full use of the arts which God has so graciously bestowed upon it, and recently have been abandoned or culturalized popularly in the church. Parton correctly sizes up the substance vs. style debate.
Also included is an excellent Addendum on Historic Liturgy as well as an excellent annotated bibliography for further study and extensive endnotes.
To be widely read.
Former Campus Crusader finds the gospel"My journey out of generic American evangelicalism is not especially remarkable," Parton writes. Indeed, in the last 20 years or so, many evangelicals have matriculated to Rome, Orthodoxy and the Episcopal church, among others. Parton tells how he discovered the evangel in confessional Lutheranism. He also issues a warning to Lutheran Christians who are more interested in mimicing the latest evangelical and church growth trends.
This book will give nondenominational types a number of items to ponder and chew on. Parton is also a first-rate apologist, and Christians of all types will benefit from the apologetic parts of the book.
If you realize you're missing something in your Christianity -- a lack of reverence for God in worship, too much emphasis on what you must continually do (sanctification swallowing up justification), a "majoring on the minors" such as end times speculation, sectarian quibbling (to name a few that I have experienced as an evangelical) -- this book is well worth your time. An excellent "For Further Study" section and notes, too.


very good book
authoritative and up-to-dateCompared to Streetman (5th Edition) coverage is narrower, without optoelectronic, microwave and power devices. For electrical engineers, this greater focus is rewarded in Casey's book with in-depth introduction to SPICE simulations of all covered devices. For MOSFETs focus is on level 1 and level 2 PSpice, with a description of higher models up to level 6, BSIM3.
In addition to PSpice, the sales point for Casey is physics of device operation. For example, it has solid discussions of intrinsic carrier density (why doesn't simple formula agree with experiment?) and of MOSFET threshold voltage. None of the other books come close for authoritative, basic argument.


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