No one knew what it 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 that it was vast... lights . . and had the potential for utter destruction. So an existing space probe was reoriented to intercept, and staffed with replicates of both humans and aliens.
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