Great pleasure can be had in sailing across a gentle, blue sea with a fair wind at the back. With little more effort than a slight nudge upon the tiller, you and your craft can travel great distances at a leisurely, enjoyable, relaxing pace. Now, replace wind and water by sail and photon as a trio of authors write in their book “Solar Sails – A Novel Approach to Interplanetary Travel“. In it, Giovanni Vulpetti, Les Johnson and Gregory L. Matloff show a very capable and promising method of local and interstellar travel.
Solar sailing uses the push of sunlight against a collector or sail to move a craft. With the absorption and/or reflection of photons, the craft continues to accelerate so that, after making a sun dive, it could travel out of our solar system at velocities in excess of 500 kilometres per second. This idea is so promising that most major national space agencies are looking into sail material and optimal flight paths.
To get you on your way, this book serves as an introduction to the idea of solar sailing. It starts with a review of rocket physics. Then there’s a section that discusses the pro’s and con’s of chemical and nuclear propulsion, as well as some more exotic ones, like Bussard’s proton-fusing interstellar ramjet. However, much of the writing serves to inform the reader of the impractical nature of such forms of propulsion. Hence, by contrast, this section capably serves to show the practical nature of solar sails.
Having provided this belief that solar sails are practical and feasible with current technology, the book continues by describing solar sails in more detail. It discusses sail manufacturing, sail craft construction and delivery, and, methods of sailing or tacking. By using common nomenclature, the book easily conveys the necessary scientific elements to both a generalist and a space enthusiast. Some times it gets a bit technical, such as when describing the use of the Jovian magnetic field as an energy source. But, these tend to make the book more valuable than overly complicated.
The book concludes with technical aspects. Here, it provides details aimed to attract the interest of graduate and post-graduate students. And, there’s lots to attract, especially as so little space validation has occurred for this technology. Whether unfurling space sails, dealing with desorption, or controlling nanobots, this book provides many challenges and lots of promise for the future but also recognizes a need for a lot of effort to reach maturity. Yet, the book shows, through references to individuals’ work and the work of national space agencies, that the concept is real, practicable and potentially very rewarding.
The next time you’re floating along on your yacht or dreaming along in your armchair, take your sailing dreams to another level. Giovanni Vulpetti, Les Johnson and Gregory L. Matloff’s book “Solar Sails – A Novel Approach to Interplanetary Travel” let you see how a well known and practised human skill can be used well away from the water’s surface. From it, we can see how Earth’s water can slip far astern while the horizons of different planets fill the view over the bow.