According to the book cover, this is what The Bluffer's Guide to the Cosmos offers you:

"Be an instant expert on the cosmos and bluff
your way in the universe.
No science required, just a sense of humour."
So the first question to ask is, does it make good on its offer? In a word: Yes.

The Bluffer's Guides are slim volumes that you could tuck into a jacket packet - Daniel Hudon's guide to the cosmos is less than ninety pages. Their angle is that they're giving you enough information to convince friends, family and people down at the pub that you know what you're talking about. Certainly the guide to the cosmos succeeds in being informative and entertaining.

The good

1. Good organization and coverage of the topic
2. Generally well-informed and accurate
3. Well written and entertaining
4. Most of the jokes

The author has neatly covered the concepts of a whole astronomy course. The detail obviously has to be selective, but the big picture is very good. Hudon zips through the Big Bang, the shape of the universe, the contents of a galaxy, our home the Solar System, black holes, dark energy and much more.

The topics are well organized and give a coherent overview of current astronomy. The writing is very readable, both in its clarity and its light touch.

Humor is, of course, a good way of communicating information, because it makes the information more memorable and keeps people's attention. For example, it's amusing to say that dark energy is "something that is easy to sound intelligent about because no one knows what it is." But it's also true. If you look, you'll find that most cosmology sites are equally forthright in admitting that no one knows what dark energy is.

The book includes not only big concepts, but also some useful definitions. I was pleased to see Hudon making the point that by "size" astronomers mean breadth, and that this isn't the same as mass. In the evolution of stars, for example, the course of a star's evolution is determined by its mass, not its diameter. Lack of clarity on this can lead to a good deal of misunderstanding.

The not so good

1. The rest of the jokes
2. Some errors

I'll concede right away that jokes are a matter of taste and not belabor this!

Unfortunately, there are a certain number of errors. Fortunately, I'd guess that even in the company of professional astronomers, you'd probably get away with them. Astronomers can be rather vague about topics outside their own specialities. Nonetheless they were unexpected in what's a quite knowledgeable book.

For example, I laughed at the list of the contents of the universe in increasing size order, starting with atoms and going to "molecules, dust, lost sets of keys, asteroids, comets, moons, politicians' egos, planets, nebulae, stars. . ." It might be a matter for discussion as to whether politicians' egos should go into the list after "moons" or after "planets". Not so with nebulae. They are diffuse but spread out - and much bigger than stars.

Oddly, the book lists it as a myth that "the tides are controlled by the Moon." It goes on to say that "though the Moon is involved in the tides, the Sun does half the work." Surely, it's the other way around, that though the Sun is involved in the tides, the Moon does most of the work, around seventy per cent according to the calculations I found on the Georgia State University website.

I was surprised to read that "the toxic 95% carbon dioxide [Martian] atmosphere means that should [travellers] take their spacesuits off they would experience the fleeting sensation of having their blood vaporize." Did something get lost in the editing here?

Even if the Martian atmosphere had a significant proportion of oxygen, you still couldn't breathe it because it's too thin. But, in any case, your blood wouldn't vaporize. It's contained inside your blood vessels and those are also safely tucked away within the rest of your body. A test subject accidentally exposed to a vacuum reported the water on his tongue beginning to boil just as he lost consciousness. Air pressure was restored and he suffered no harm from his half-minute exposure to the vacuum.

The verdict

I've already given this book a thumbs up and you've probably realized that it's written for an adult audience. This is not because it contains X-rated material, but because the language, jokes and general approach are adult and not likely to be appreciated by children.

The Bluffer's Guide to the Universe is fun and would make a nice little present. I found it a bit like having someone telling funny stories at a party. I enjoyed reading it and you probably know someone who would too.

Bluffer's Guides are widely available in Britain. Readers elsewhere can get them online or order them from book stores.

The Bluffer's Guide to the Cosmos, author: Daniel Hudon, published by Little, Brown: 2005, ISBN: 978-1-903096-42-0

(1) "Why We Have Tides," https://hyperphysics.phy-astr.gsu.edu/hbase/tide.html#mstid
(2) Geoffrey A. Landis, "Human Exposure to Vacuum" https://www.geoffreylandis.com/vacuum.html

NOTE: The copy of The Bluffer's Guide to the Universe which I read was provided by the author.