This series of four books marks the 50th anniversary of the start of the space age which opened with the launch of Sputnik in 1957, by providing a comprehensive account of how we have used robotic spacecraft to explore the Solar System. It starts with a review of what we knew - or thought we knew - about the Solar System immediately prior to dispatching the first space probes, and then discusses each project and the results obtained, to progressively explain how our knowledge of the Solar System has increased over the years. Part 4: The Modern Era 2004 - 2012" focuses on the robotic missions initiated since 2004 including NASA's Mars Reconnaissance Orbiter the Phoenix Mars lander the Curiosity rover the foiled Russian mission to the Martian moon Phobos the joint NASA-European orbiters and rovers for Mars and attempts by China Japan and India to send probes. "Part 4" also discusses missions to other destinations including the Rosetta Deep Impact and EPOXI comet missions the MESSENGER or