Contact - Carl Sagan [93]
When it happened, it was Willie once again, this time on the graveyard shift, who first noticed. Afterward, Willie would attribute the speed of the discovery less to the superconducting computer and the NSA programs than to the new Hadden context recognition chips. At any rate, Vega had been low in the sky an hour or so before dawn when the computer triggered an understated alarm. With some annoyance, Willie put down what he was reading-it was a new textbook on Fast Fourier Transform Spectroscopy-and noticed these words being printed out on the screen:
RPT. TEXT PP. 41617-41619: BIT MISMATCH 0/2271. CORRELATION COEFFICIENT 0.99+
As he watched, 41619 became 41620 and then 41621. The digits after the slash were increasing in a continuous blur. Both the number of pages and the correlation coefficient, a measure of the improbability that the correlation was by chance, increased as he watched. He gave it another two pages before picking up the direct line to Ellie's apartment.
She had been in a deep sleep and was momentarily disoriented. But she quickly turned on the bedside light and after a moment gave instructions for senior Argus staff to be assembled. She would, she told him, locate der Heer, who was somewhere on the facility. This proved not very difficult. She shook his shoulder.
"Ken, get up. There's word that we've repeated."
"What?"
`The Message has cycled back. Or at least that's what Willie says. I'm on my way there. Why don't you wait another ten minutes so we can pretend you were in your room in BSQ?"
She was almost at the door before he shouted after her, "How can we recycle? We haven't gotten the primer yet."
Racing across the screens was a paired sequence of zeros and ones, a real-time comparison of the data just being received and the data from an early page of text received at Argus a year before. The program would have culled out any differences. So far, there were none. It reassured them that they had not mistranscribed, that there were no apparent transmission errors, and that if some small dense interstellar cloud between Vega and the Earth was able to eat the occasional zero or one, this was an infrequent occurrence. Argus was by now in real-time communication with dozens of other telescopes that were part of the World Message Consortium, and the news of recycling was passed on to the next observing stations westward, to California, Hawaii, the Marshal Nedelin now in the South Pacific, and to Sydney. Had the discovery been made when Vega was over one of the other telescopes in the network, Argus would have been informed instantly.
The absence of the primer was an agonizing disappointment, but it was not the only surprise. The Message page numbers had jumped discontinuously from the 40,000s to the 10,000s, where recycling had been uncovered. Evidently Argus had discovered the transmission from Vega almost at the moment it first arrived at Earth. It was a remarkably strong signal, and would have been picked up even by small omni directional telescopes. But it was a surprising coincidence that the broadcast should arrive at Earth at the very moment Argus was looking at Vega. Also, what did it mean for the text to begin on a page in the 10,000s? Were there 10,000 pages of text missing? Was it a backward practice of the provincial Earth to start numbering books on page I? Were these sequential numbers perhaps not page numbers but something else? Or-and this worried Ellie the most-was there some fundamental and unexpected difference between how humans thought of things and how