Heavenly Errors

Rating:
Summary: Explains how science really works
Review: Comins (physics and astronomy, Univ. of Maine) provides an informal and engaging discourse on the misconceptions that hinder people from fully understanding the natural world and from discriminating between fact and fraud in everyday life. He uses astronomical examples to illustrate the differences between how nature actually works and how people tend to perceive how it works. Drawing on his experience teaching large science classes, he ruminates on why it is that students enter college with deep-seated misconceptions that prove difficult to correct using traditional lecture-style teaching. The book has a few minor shortcomings worth noting. Some chapters ramble a bit off subject. Much of the posited causes of misconceptions about nature are subjective or anecdotal, not necessarily backed by rigorous research conducted by learned specialists. Chapter 6 contains an unabashed pitch for the author's own elementary astronomy text. Quibbles aside, Heavenly Errors is an interesting new look at how humans perceive nature. Science teachers may find useful the Web-accessible database that Comins has compiled over the years, as well as some of the teaching strategies he describes. Interesting reading for anyone interested in science teaching or public outreach and useful for undergraduate seminars. A good primer on critical thinking and how science really works.

Rating:
Summary: Really wanted to give it 3 1/2 stars--better than middle
Review: Considering the misinformation of the general public on astronomical matters (and matters in general), this book casts a welcome light on some of them. The author, further, has a web site listing even more misconceptions, given by students in his classes as well as contributors from his web site audience. The author also delves into the Why of how these misconceptions have arisen in people's minds.

The book is not perfect, and in fact could lead to the furtherance of some other misconceptions. For example, he lists a flat No to the question of whether black holes are black. A correspondence with the author indicates he was thinking of small black holes--with considerably less mass than the moon. Such small black holes would indeed glow, via Hawking radiation, but larger ones would indeed be black by anyone's standards, including those multi-solar-massive ones hypothesized to be at the centers of galaxies. However Prof. Comins' reply did rid me of my misconception that it is only for a short period of time that small black holes glow.

Alluding to the fact that the moon keeps the same side toward the earth all the time, the book states that in the lunar sky, the earth "won't budge, no matter how many days, weeks, months, years, or decades you watch it". In actuality, due to the eccentricity of the moon's orbit and the tilt of its axis relative to its orbit, the moon's center librates as seen from the earth, and as seen from the moon, the earth moves in the sky with a range of 16 degrees East-West (8 degrees either way from center) and 13 degrees north-south. As a result the earth could get to be 20 degrees from where you first saw it. That's 10 earth diameters, or 40 earth-viewed full moon's width, so it really more than "budges". Prof. Comins explains in correspondence that he "chose to be glib about this point because it would take quite a lot to describe issues related to libration from scratch with only a small gain in insight by the general reader." Yet one of his listed misconceptions was of the center of mass of the moon's core being at the geometric center of the moon; that difference is only about 1/2 mile, out of the 2000-mile lunar diameter.

In the book, Prof. Comins states that it is never safe to look directly at the sun without a proper solar filter. He doesn't exempt looking at the corona during totality of a solar eclipse. In his correspondence, he states "Concerning looking directly at the Sun during a total eclipse, it is definitely not safe to do so. A close friend of mine lost a significant amount of his vision doing so. Looking directly at the corona during a total eclipse is still extremely dangerous. Keep in mind that the Sun is in totality for only a matter of minutes, and as soon as it comes out, its brightness is dangerous." While I can understand the impact of personal tragedies, it's also true that people travel thousands of miles to view totality directly. I have done so four times and viewed the totally eclipsed sun with the unaided eye and even through a telescope. And to do so, one cannot have a filter, and my eyes are unscathed, as are those of many hundreds, or thousands, who go on eclipse cruises and expeditions. They have accurate predictions of the timing and accurate timers, and call out to all to "look away" at the appropriate time. As the NASA web site on eye safety during solar eclipses states: "In spite of these precautions, the total phase of an eclipse can and should be viewed without any filters whatsoever. The naked eye view of totality is completely safe and is overwhelmingly awe-inspiring!"