Dr. Hanslmeier has written a wonderful introduction to the cosmos that is accessible to anyone with an interest in “what’s out there and how do we see it.” This book covers a wide variety of astronomical topics ranging from our solar system with its constituent planets, to stars, telescopes, quantum particles, radiation, gravitational waves, and satellite telescopes that scan the cosmos.

The book begins with a look at stars and planets and discusses light radiation, parallax, and astronomical measurement techniques. The author provides a welcome introductory explanation of light and whether it is a particle or a wave with illustrations to support both approaches.

Next, the text discusses modern telescopes and shows how optical telescopes collect light and magnify targets for the viewer. Sprinkled throughout are equations and technical details to whet the reader’s appetite for further study, but the author does not dwell on these details other than to present them as support for his writing and to show his enthusiasm for astronomy. This approach gives the book a technical feel while allowing non-technical readers insights and results which may be skipped, if desired, without losing the overall ideas and flow.

I thought the historical details and pictures about telescopes and observatories were captivating and convey to the reader just how much work and construction is needed to study the heavens.

Chapter 3 shows us galaxies in the skies and introduces the reader to Edwin Hubble who showed the universe is expanding at a rapid rate and cooling as well. Again, the chapter is filled with lovely pictures to illustrate the points and help the reader understand the concepts.

Radio telescopes are introduced in Chapter 4 where we meet black holes and radiation spectra. Albert Einstein’s prediction of gravitational waves is described in Chapter 5. These new phenomena are briefly described, and the author shows us how they were detected. I was familiar with the ideas at a superficial level, and I thought the author presented the ideas superbly for the beginner reader.

Our journey into new ideas continues in chapter 6 with neutrinos and quantum physics. Once again, the author presents the key ideas in a manner sufficient for a high-level understanding without confusing the novice reader with too many equations. Concepts such as spin, charm, and charge are illustrated with diagrams and further discussion to clarify the ideas.

The final two chapters discuss the Hubble Space Telescope and the James Webb Telescope. Here the author describes, for example, how one of the mirrors on the Hubble Telescope suffered spherical aberration and caused blurry images. The error was corrected, and Hubble has since been providing remarkable images of the planets and galaxies in the universe. Of course, Hubble has aged so the last chapter describes the James Webb Telescope with details of its construction, launch, and images.

This is a short book which covers a wide range of topics at a general science level. I finished the book wanting more which, I think, shows what a good book this is for an interested reader. I would have welcomed a summary chapter with the author’s thoughts on where our space explorations are heading and what new discoveries we might see. Still, Dr. Hanslmeier has written a concise and thoughtful introduction to the heavens. It was a pleasure to read.

David S. Mazel is a practicing engineer in the Washington, DC, area.