The popular host of the BBC's award-winning Stargazing Live takes readers on an imaginary journey throughout our solar system.
Although many elements of such a trip are not yet possible, Thompson (A Down to Earth Guide to the Cosmos, 2013, etc.) makes it believable enough. First, as the author notes, traveling toward Mercury and Venus is relatively easy because the sun's gravitational pull would provide assistance. Journeying to the outer planets such as Neptune and Pluto is, of course, more difficult. Fortunately, an advanced propulsion system, the newly developed “Variable Specific Impulse Magnetoplasma Rocket,” could do the job. Thompson explores the latest thinking about the origins of the moon and planets—e.g., the idea that our moon was created out of debris when “a large object about the size of Mars [may have] struck earth around 4.5 billion years ago.” A serious problem that voyagers would face is shielding themselves from cosmic radiation, which has been experienced by astronauts who report “seeing flashes of white,” a phenomenon currently attributed to “cosmic rays passing through their heads.” Growing food, disposing of waste, exercise, recreation, and even intimate relations would need to be factored in to planning such a lengthy trip. Another necessity would be replicating gravity. A tempting stopover might be Jupiter's moon, Titan, which appears to be “similar to Earth when it was in a more primitive state.” Thompson claims that it could support “primitive alien life, and he discusses the 1972 “ ‘flotilla’ of unmanned space ships that…already visited the outer Solar System” and relayed information back to Earth. It is this data that informs Thompson’s speculations, many of which are intriguing. Unfortunately, the author is writing about a well-mined subject. Despite his mostly appealing prose and useful details, the book, which could have been more fully fleshed out, suffers in comparison to Julian Guthrie’s recent How to Make a Spaceship (2016).
Thompson is a knowledgeable and capable guide, but his many fans may prefer to stick to his TV shows.