Answer:
Wernher von Braun
Explanation:
Wernher von Braun was a German scientist and physicist who in his non fiction book " The Mars project" mentioned about expedition to mars by man. This book outlined technical specification for a manned expedition to mars in 1948.
He envisioned a large space expedition where 70 crew members on 10 space crafts shall spend 443 days on the surface of mars. He even calculated the size and weight of ships and the required fuel.
