Tag Archives: Phil Plait

Review 70: Bad Astronomy


Bad Astronomy by Phil Plait

What do you think you know about astronomy? For example, what causes us to have seasons? If you said that it’s our distance from the sun – sorry, you’re wrong. Or how about why the sky is blue? If you think it’s that the sky reflects the sea, nope. Wrong again. Or perhaps you think that the moon’s tidal effect makes people crazy, or that an egg can only stand on end if it’s the Vernal Equinox or that an alignment of the planets will cause a terrible buildup of gravity that will kill us all!

All wrong. But you would not be alone. For a society as technologically advance as ours (and if you’re reading this, then chances are good that you live in a technologically advanced society), the general public has a big problem with science. People see it as being too hard to understand, or too removed from their daily lives. Politicians bemoan the fact that American schoolchildren are falling behind in science, but science funding is almost always on the list of cuts that can be made to save money. We love technology, but hate science, and that is a path to certain doom.

Of all the sciences, though, astronomy is perhaps the worst understood. A lot of people still confuse it with astrology, which is probably a huge part of the problem right there. For millennia, we have thought about the planets and stars as celestial things, unknown and unknowable by such base creatures as ourselves. It’s only in the last hundred years or so that we’ve been able to rapidly improve our understanding of the universe, and popular knowledge hasn’t caught up with that yet.

And so bad misconceptions of astronomy persist in the public imagination.

Fortunately, we have people like Phil Plait to set the record straight, and that is indeed what he does in this book.

While there are many educators out there who believe that a wrong idea, once implanted, is impossible to eradicate, Plait sees it as a teachable opportunity. Take, for example, the commonly held belief that on the Vernal Equinox – and only on the Vernal Equinox – you can balance an egg on its end. Many people believe this, and it’s an experiment that’s carried out in classrooms around the country every March. Teachers tell their students, and the local news media tell their viewers, but no one stops to ask Why. Why would this day, of all the days in the year, be so special? More importantly, how can we test that assertion?

Fortunately, that’s within the powers of any thinking individual, and it should be the first thing teachers do once they’ve finished having fun balancing eggs: try and do it again the next day. If you can balance an egg on April 3rd, or May 22nd or August 30th, or September 4th or any other day of the year, then you have successfully proven the Equinox Egg Hypothesis wrong. Congratulations! You’re doing science!!

Or perhaps you’ve heard the story that you can see stars from the bottom of a well, or a tall smokestack. This is because, the idea goes, the restricted amount of light will not wash out the stars so much, giving you a chance to do some daytime astronomy. Well, there’s an easy way to test this one too, if you have an old factory or something of that nature nearby. What you’ll discover is that no matter how much you try to restrict your view of the sky, it’ll still be washed out and you won’t see any stars at all.

One more good one that a lot of people believe – the moon is larger in the sky when it’s near the horizon than when it’s at its zenith. Again, this is something that’s very easy to test. Go out as the full moon is rising, looming large in the sky, and hold up an object at arm’s length – a pencil is usually recommended. Make a note of the moon’s apparent size as compared to the eraser. Then go out again when the moon is high in the sky and repeat your observation. The moon appears to be the same size, no matter how it may look to you.

Of course, there’s a lot of science into why these things are the way they are. The chicken egg thing is because there’s no singular force that is only acting on chicken eggs and only doing so on one day of the year (which is not even universally regarded as the first day of spring). As for the inability to see stars in the daytime, that’s because our pesky atmosphere scatters a lot of the light coming from the sun, so light appears to come from everywhere in the sky. The only thing you’re likely to see in a blue sky is the moon, and MAYBE Venus, if you’re really sharp-eyed and lucky.

The Moon Illusion is not well-understood, actually. It’s probably not the brain comparing the moon with objects on the horizon – the effect works at sea, too. It’s probably a combination of competing psychological effects that deal with distance, none of which can accurately deal with how far away the moon is.

Regardless, all of these things are easily testable by anyone. The problem is that so few people take that extra time to actually test them, or even think that they should.

There are some myths and misconceptions that take a little more expertise to explain, such as why tides and eclipses happen, how seasons occur and why the moon goes through phases. But these explanations aren’t very difficult and are well within the understanding of any intelligent adult. Unfortunately, there are a lot of myths that are stubborn, entrenched into the heads of people everywhere and very hard to get out. Not the least of these are the beliefs that UFOs are alien spacecraft and that we never went to the Moon.

Interestingly enough, both of these rest on the same basic problem: we can’t rely on our own brains to accurately interpret the data that we see. Plait recounts a story where he was mesmerized by some strange lights in the night sky while watching a 3 AM shuttle launch. They seemed to hover in place, making strange noises, and it wasn’t until they got much closer that he was able to see them for what they were: a group of ducks that were reflecting spotlights off their feathers.

Our brains believe things, and interpret the observations to fit those beliefs. So when the dust on the moon doesn’t behave the way we expect dust to behave, some people believe that to be evidence of fraud, rather than the natural behavior of dust on the moon. We are creatures of story, which is why we like conspiracy theories and astrology. We want the world to make a kind of narrative sense, so often the first explanation we come up with is a story that sounds good. Unfortunately, just because the story sounds good, that doesn’t make it true.

He also takes a swipe at bad movie science, but in a good-natured manner. Even he admits that movies are more likely to favor story over science, but there are some common errors that make it into so many science fiction films – sound in space, people dodging lasers, deadly asteroid fields – these things may be dramatically interesting, but they’re all bad science. And while it would be annoying and pedantic to pick out every example of how the rules are bent for sci-fi (“Please. Why would the aliens come all the way to Earth to steal water when it exists in abundance out in the Kuiper Belt? I scoff at your attempt!”), they do offer an excellent opportunity to teach people about how science works.

One of the things I’ve always liked about Plait is his obvious enthusiasm for not just astronomy but for science in general. Here we have this excellent system to cut through the lies our brains tell us and get closer to knowing what’s actually going on. Science forces us to question our assumptions, look at things from many points of view, and arrive at a conclusion that best describes the phenomenon we’re observing. When Plait talks about science, he is not condescending or dry or super-intellectual, the way so many people imagine scientists to be. He’s excited that he gets to use this amazing tool for understanding the universe, and he wants other people to use it.

If you’re an astronomy buff, like myself, you probably won’t learn much new information from this book. But hopefully you’ll be re-invigorated to go out there and look at the world through a scientific, skeptical eye, and you’ll be willing to confront these misconceptions when next you come across them. Even better, you might start thinking about what else you think you know, and how you can go about testing it.

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“If a little kid ever asks you just why the sky is blue, you look him or her right in the eye and say, ‘It’s because of quantum effects involving Rayleigh scattering combined with a lack of violet photon receptors in our retinae.'”
– Phil Plait, Bad Astronomy
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Phil Plait on Wikipedia
Bad Astronomy on Wikipedia
Bad Astronomy on Amazon.com
The Bad Astronomy Blog

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Filed under astronomy, education, media, nonfiction, Phil Plait, pseudoscience, science, skepticism

Review 24: Death from the Skies!


Death From The Skies! by Phil Plait

I’ve always found the end of the world fascinating. So many cultures have put together their own ideas of how the world will end, from the Norse Ragnarök to the Christian apocalypse to the Hindu cycle of creation and destruction. We live in a world that was, for a long time, unpredictable to us and on many occasions seemed to be outwardly hostile. Our ancestors faced floods and earthquakes and disease, with no idea of where these things came from, why they happened or how to stop them. And so they made myths and stories to explain the dangerous world in which they lived. From that, they extrapolated – if the world is this dangerous now, how dangerous could it be if it really tried? And so came our myths of a world that not only succeeds in hurting us, but in wiping us out altogether.

Even in the modern age we have our myths. Books, television, and movies all use the end of the world (or end of a world) to tell stories – usually about the resilience of mankind and our ability to pick ourselves up, dust ourselves off, and rebuild human society, hopefully for the better. As good as this is for fiction, there are two problems when we try to apply these myths and stories to the real world: the world will end, one way or another, and no amount of heroics, cleverness or pluck will save us. Not in the long term, anyway.

Science has accomplished what religion and fiction could not – it has seen the future and can make fairly accurate prophecies about how this world, and our civilization upon it, will die. Renowned astronomer Phil Plait is your prophet for this trip into all the ways the world will end….

In this book, Plait looks at nine possibilities for the end of the world as we know it. In order, they are:

Death by Impact
Death from the Sun
Death by Supernova
Death by Gamma Ray Burst
Death by Black Hole
Death by Aliens
Death of the Sun
Death by Galactic Collision
Death of the Universe

In each chapter, Plait outlines the ways in which that specific event could injure or kill us, with as much science as he can comfortably put in. He explains, for example, why we can’t just send Bruce Willis up to hit an incoming meteor with a nuke (it probably won’t work) and why any black holes produced by the LHC won’t do us any harm. He looks at how a supernova happens, what it is about a black hole that turns it into one of the deadliest weapons in the universe, and tries – very, very hard – to make the reader understand exactly how long “forever” is. (Hint: it’s a lot longer than you think. Longer than that, even. Nope, keep going….)

Each chapter outlines the processes by which we could experience the destruction of our civilization or, in a few cases, the planet itself. He looks at the scientific foundations of these events, explaining in detail what it is about the sun, for example, that makes it a cauldron of chaos and torment, or why we really, really don’t want to get even a smallish black hole anywhere near the planet. And I have to say, of all the unlikely ways we could be toasted, gamma ray bursts are my favorite – a deadly beam of energy from thousands of light-years away, cooking the planet all the way down through the crust and utterly devastating the planet’s ecosystem so as to kill off anyone who was lucky enough to be on the other side of the world. I mean, wow. And there’d be no warning, either. By the time we knew what was happening, it’d be too late. So that chapter (with a line paying homage to Douglas Adams, even) is just mind-boggling.

Probably my favorite chapter, though, is the one about supernovas, mainly because his careful, step-by-step description of exactly how a supernova occurs made me think, “What I wouldn’t give to see that in person,” disregarding the fact that a) the best parts would happen way too fast for me to observe and b) it would vaporize me. Still, it’s a beautiful and terrifying chain reaction, which Plait describes in fantastic detail. The other chapter that evoked the same reaction was the one on the end of the universe. Despite timelines for which the word “vast” is terribly inadequate, Plait tells us what science knows about how the universe will end – the ever-increasing expansion of spacetime, the eventual death of the stars, evaporation of galaxies, the reign of the black holes and the slow, careful deaths which even they face. It all ends in darkness, all matter gone into a few stubborn subatomic particles and the eventual collapse of the very fabric of space and time.

And as bleak and miserable is the future looks, I still thought, “I really want to see that.” So if I can figure out how to live one googol years (that’d be a one with one hundred zeros after it [1]) and not have my very atoms decay into nothingness, then I’ll be able to… um… be really, really bored, probably. Since after that, there’s absolutely – literally – nothing to do. Until the universe experiences vacuum collapse, or a brane collision, possibly hitting the reset button on the cosmos and we get to do it all over again….

Most of what’s in the book isn’t new to me, but that’s probably because I grew up reading Cosmos, and I follow countless science TV shows, podcasts and blogs (including Plait’s own Bad Astronomy blog, which is well worth keeping up with, as well as his regular appearances on SETI’s podcast, Are We Alone? and occasional guest appearances on The Skeptics’ Guide to the Universe – both of which make for excellent listening). For people new to astronomy, though, this will be a rather dense learning experience – and reading it will be time well spent.

In addition to its user-friendly style, I really like the way it’s arranged – from small-scale (relatively) to large, with “Things that are absolutely certain to happen” at the beginning and end, and with “things that probably won’t happen” in the middle. And my favorite aspect of this book is that each chapter begins with a short vignette describing that particular end of the world, from the perspective of someone watching it happen. It’s not something you often see in books of this nature, and I’m really glad that Plait decided to put it in there. It makes it a little less academic and abstract and more real.

For all its death and destruction, the book isn’t really a downer. For one thing, while things like asteroid impacts and the death of the sun are inevitable, they don’t have to be fatal, and Plait describes a few ways in which – in theory – we (or our distant, distant descendants) might be able to avert or at least mitigate these catastrophes. It’s not easy, of course, but saving the world never is.

It’s mainly a marvel at the forces that surround us in the universe. It’s easy to forget, looking up at the sky from our brief, limited scale, that the universe isn’t just some pretty lights drifting about in empty blackness. Things are exploding and dying, burning and freezing, moving quickly and slowly – the cosmos is replete with activity and danger. Most of the universe isn’t just uninhabitable, it’s actively hostile to life as we know it. And yet, without the black holes, the supernovas and the galactic collisions, without massive meteor impacts and breakaway comets, solar flares and deadly radiation – without all that, life probably wouldn’t exist at all. So read this book, and take a moment to appreciate how lucky we are to be here at all, all things considered….

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“They say that even the brightest star won’t shine forever. But in fact, the brightest star would live the shortest amount of time. Feel free to extract whatever life lesson you want from that.”
– Phil Plait, Death from the Skies!
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[1] 10 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000

Phil Plait on Wikipedia
Bad Astronomy blog
Death from the Skies! on Wikipedia
Death from the Skies! on Amazon.com

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