There are problems with Lives of the Planets. Its biology is clearly based on popular works — Gould, Dawkins, and so forth — and is not always accurate. Corfield explains that "punctuated equilibrium predicts that populations experiencing restricted gene flow will undergo bursts of incredibly rapid evolution", presumably confusing it with "founder effect". His treatment of history is unsophisticated and in places wrong: he asserts, for example, that the Germans and Scandinavians navigated into the Mediterranean in preclassical times, before the Greeks and Romans.
On his core topics of solar system exploration and planetary science, however, Corfield seems more solid, and covers less well-trodden ground. He has nothing new to say about Galileo or Newton, but he also introduces less well-known figures such as George Wetherill and Michael Minovitch. Perhaps most importantly, Lives of the Planets is an extremely easy and entertaining read.