The UN Security Council had given them forty-eight hours because forty-eight hours was the interval at which the signal repeated. Every two days, at 0347 Greenwich Mean Time, the array at Titan Station received the same twelve primes, the same offset, the same patient waiting silence afterward. Whoever was sending it had been sending it for nineteen months before the array's automated filters had flagged it as anomalous. The thought of that — nineteen months of unanswered patience — sat in Solaris's chest like a stone.
She walked the length of the observation deck alone after the council session ended, watching Saturn's rings catch the distant sun. At this distance the rings looked like brushstrokes, careless and magnificent. She had grown up on Earth reading science fiction that imagined first contact as collision — armadas, invasion, the sudden terrible sky. The reality was so much quieter that she couldn't decide if it was a relief or an additional terror.
Her communicator chirped. Vance.
"Commander. The mathematics team has a proposal." A pause. "It's either very clever or very stupid. Possibly both."
"I'll be there in ten minutes."
She took one more look at the rings. Somewhere beyond them, beyond the outer planets and the long dark between stars, something was sitting at a radio array and waiting. She wondered if it was afraid too. She wondered if that was a thing it could be.