Raymond L. Weil: The Slaver Wars series
Disaster has struck the first Moon landing to be attempted in years. Commander Jason Strong and his fellow lunar explorer Greg Johnson have become stranded with no way home. In desperation, they set off in their lunar rover to check out an anomaly they discovered on their descent. What they find will shake their beliefs and what they know of human history. It is the beginning of an adventure that will take them far out into the Solar System and to a discovery that is beyond belief.