While the scientific "facts" are dated, this is still a good story. For the main message is not about what kind of life, if any, there is on Mercury or Mars, it is about the mindset of the humans that will venture into and colonize areas beyond the Earth. Roy is a young man participating in a quiz show where the subject is about airplanes, space ships and space travel. The prize is supposed to be an all-expenses paid flight to anywhere on Earth. However, Roy has set his sights much higher, when he wins; his request is to go to Inner Station, an artificial satellite orbiting the Earth. After some vacillation, World Airways agrees to allow him to go.
Roy arrives on Inner Station and begins his tour as a space traveler. He learns quickly and also discovers the mindset of the men who fly in space. It is one of adventure, constant danger and good times. When his tour is over, Roy knows that he will be coming back, as he is determined to make space his career.
The book is written in typical Clarke style, with scientific details used to explain whenever possible. He describes the computational problems of space flight, how you must chart a course to where the target will be when you get there, not where it is now. Clarke also describes some of the difficulties and the level of skills needed to bolt things together in space. Although much has changed since 1952 in the realm of scientific fact, the human personality has not and other than including females in the crews, the people described in this book will be models for people traveling in space a century from now.