Cuckoo was coming.
No one knew what is was - but everyone knew it was trouble.
Designated Object Lambda when it first appeared on the fringes of the galaxy, 20,000 light-years away, it was traveling at one-sixth the speed of light.
The astrophysicists said thet it was vast... light... and had the potential for utter destruction. So an exiting space probe was reoriented to intercept; it was staffed with replicates of both humans and aliens.
Then the space probe began to leak radiation...
Genres: science fiction
Jack Williamson (John Stewart Williamson, 1908–2006) was an American science fiction author.
Jack Williamson has been in the forefront of science fiction since his first published story in 1928. Williamson is the acclaimed author of The Humanoids and The Legion of Time. He is considered to be "The Dean of Science Fiction".
Jack Williamson. Wikipedia.