Troubled star

"Troubled Star" by George O. Smith is a science fiction story from the 1950s, exploring the complications of space travel and how different species interact when they're at different points in their technology journey. The story follows Chat Honger, Bren Fallow, and Scyth Radnor, who are part of a highly advanced group setting up markers across the galaxy; while Dusty Britton is a famous Earth spaceman facing strange problems after he says he met aliens at sea. As the Earth government and public doubt Dusty's story, the book builds to a standoff in space as the characters struggle with what might happen to Earth and how civilization will change.