Colors of Space, The by Marion Zimmer Bradley (1930 - 1999)

About

Bart Steele, Space Academy graduate, is on his way home to his father's business - he runs a fleet of spaceships for interstellar travel. The secret for fast interstellar travel though is still tightly kept by the alien race Lhari. An agreement between humans and Lhari has been made that permits humans only to travel in cold sleep as passengers aboard Lhari vessels as to not reveal the secret.Some humans – the Mentorians - have had a slight genetic shift which enhanced their vision to withstand the light levels that the aliens Lhari use and live in. Mentorians perceive a wi...