Classic Space was one of the first major themes to appear in the late 1970s, and continued for over a decade after that, eventually evolving into other space themes. It featured no enemy, but rather astronauts in different uniforms who generally worked together. The focus was exploration, not fighting or resource collecting, which is a significant difference from some of the space sets of today. It seems in many ways to bridge the gap between the City and Town space sets (focusing on shuttles and training on earth) and the more fanciful space sets (Space Police, Mars sets, etc.)
An interesting looking set! It features the moveable claw that is seen in other space sets, as well as the neon transparents screens that appeared in many space sets over the years. While it looks like a base, the legs actually move (though I'm not exactly sure how) making it more of a large exploratory base, perhaps scientific in origin. As I mentioned earlier, we see a blue and red space man (there are also yellow and white (more common) and the rare black) working together. Not sure why they have different colors to be honest.
There are also rockets in the middle of the ship, which would fire upwards. While many Classic Space ships feature weaponry, it's never really explained why they even need it. Perhaps there is conflict, but further investigation will be required.