I purchased this book in May 2021 at a National Park. I selected this book from among many other astronomy books on the shelves because it seemed to have the most detailed information. It is also very compact, small enough to carry in a backpack or in a car's glove box.
Before I saw this book on the shelf, I had no idea that the Audubon Society publishes field guides on many other topics besides birds. Now I know, and am now interested in several of their other field guides.
This book was copyrighted in 1991. It states that this is the 26th printing, March 2021. However, the book wasn't updated with the latest information. Much of the data in the appendices is outdated, such as all dates for lunar and solar eclipses. The data in the appendices are for astronomical events occurring in 2013 through 2020. And a bit of the main text is outdated as well. For example, Comet NEOWISE's naked eye appearance in 2020; and the orbiting of, and subsequent landing upon, Comet 67P/Churyumov–Gerasimenko in 2014, are not included in this book. Comet Hale-Bopp's 1997 appearance Is mentioned in the text and included in photos however.
Aside from the missing current information, this book is a great reference. Every person who is interested in viewing and learning about the night sky, and astronomy in general, should carry a copy of this, or a similar, book inside their backpack or car.
(As companions to this book, I purchased a planisphere for my latitude, and sets of small cards that have depictions of how the 88 official constellations look, according to an artist's imagination, to better help my mind connect the dots when I look up at the night sky. Don't forget red light headlamps with adjustable brightness.)