In January 2011, a 10-year-old New Brunswick girl became the youngest person to discover a supernova, or exploding star, situated about 240 million light years from Earth. Technology, especially as it applies to telescopes at well-placed observatories around the world, has dramatically improved our ability to map stars and has accelerated the discovery of many new planets over the past 15 years or so. For those who like to look to the skies, these are exciting times, argues Ray Jayawardhana, Canada Research Chair in observational astrophysics at the University of Toronto.

In his overview of cosmic exploration, Jayawardhana predicts that before the decade is out, dozens of so-called “alien Earths” may be discovered and examined for signs of life. That may seem awfully hopeful, but what becomes clear is that, when it comes to astronomy, nothing is clear. We’ve ­visited the moon, and we take for granted the Copernican Revolution, the Hubble telescope, and the Doppler Effect, but our best assessments of the cosmos are highly speculative. Entire theories can be undone by the position of clouds or an accidental knock of a telescope. The author offers a roster of ­historical hypotheses about the formation of planets, all of which were later shot down by more recent discoveries.

The field of astronomy, we learn, is not populated exclusively by telescope-toting ­eccentrics. The marketplace of planet hunters is also teeming with bulldog-like academics in search of discovery, glory, immortality, or, sometimes, just grant money to keep a project going. However, this book reminds us that all of history’s paradigm-shifting ideas were spawned by people who, in the end, simply longed to know more about the universe and our place in it.

Although it occasionally gets bogged down in science-heavy prose and planetary minutiae – the book includes a 10-page glossary – Strange New Worlds offers a valuable assessment of the state of the cosmos.