Hoshi wo Tsugu Mono

Hoshi wo Tsugu Mono (星を継ぐもの) is a manga series by James Patrick Hogan with illustrations by Yukinobu Hoshino. It was serialized in Big Comic.

Plot
Moon investigator found a dead body of a person wearing red space suit. And this corpse was about 50,000 years old. What is a relation between modern humans. Also they found a space ship at Jupiter after a while, where space ship isn't made from earth.