If 'Oumuamua Is an Alien Spacecraft, It's Keeping Quiet So Far..
[livescience.com]
Back in the early 60's there was a 6 book juvenile Sci/Fi series about 3 young men traveling the solar system, they were called ,if I recall, Explorer Patrol. One of the books dealt with a rogue asteroid they landed on that was a interstellar Ark. I remember to this day about it as this type of story is one of my favorite scenarios.
"Sometimes a cigar is just a cigar." - Sigmund Freud.
Very apropos phrase!