I am a professional software engineer with a long interest in computer graphics and the space program. As a child in the 1960s I remember the USA’s Gemini program, then Apollo. The space project that most fascinates me is the Viking '75 unmanned spacecraft to Mars, launched in 1975 (thus the project name) and landed in 1976. I have been using SketchUp to create a detailed and high-fidelity model the Viking lander, which I started in 2013.