Robert Sawyer - Ineluctable

And then they could determine whether these people and the members of would be able to share a world together.

“They’re not at Groombridge 1618,” Darren said to Mayor Rivers, when His Honor arrived shortly after midnight; the mayor’s toupee had been hastily perched and now sat somewhat askew atop his head. “They can’t be. Assuming they responded immediately upon receipt of our message, they’re only a few light- hours away—about the distance Pluto is from the Earth, although, of course, they’re well above the plane of the solar system.” Darren frowned. “They must be in a spaceship, but … but, no, no, that can’t be right. Every observatory on Earth has been taking the spectra of the laser flashes, and they’re dead on the D1sodium line, which can’t be a coincidence. The senders are using a line that’s weak in their home star but very strong in our own sun’s spectrum to signal us. But, like I said, it’s dead on that line, meaning there’s no Doppler shift. But if the ship was coming towards us, the light from the laser would be blue-shifted, and—”

“And if it were a-flyin’ away from us,” said Mayor Rivers, “it would be red-shifted.”

Darren looked at His Honor, surprised. Rivers lifted his shoulders a bit. “Hey, we’re not all hicks down here, you know.”

Darren smiled. “But if the light isn’t undergoing a Doppler shift, then—”

“Then,” said Rivers, “the starship must be holdin’ station, somewhere out there near the edge of the solar system.”

Darren nodded. “I wonder why they don’t come closer?”

The next night, Darren found himself flipping channels in his hotel room—they’d put him back in the Hilton. Letterman did a top-ten list of people who would make the best ambassadors to visit the aliens ( “Number four: Robert Downey, Jr., because he’s been damn near that high already” . And Leno did a “Jay Walking” segment, asking people on the street basic questions about space; Darren was appalled that one person said the sun revolved around the Earth, and that another declared that Mars was “millions of light-years” away.

After that, though, he switched to Nightline , which had some more-serious discussion of the aliens. Ted Koppel was interviewing a guy named Quentin Fawcett, who was billed as an “astrobiologist.”

“I’ve been studying the anatomical charts that the Tailiens sent us,” said Fawcett, whose long hair was tied into a ponytail. “I think I’ve figured out why they don’t use radio.”

Koppel played the stooge well. “You figured that out from anatomical charts? What’s anatomy got to do with it?”

“Can we have the first slide?” asked Fawcett. A graphic appeared on the monitor between Koppel and Fawcett, and, a second later, the image on Hamasaki’s hotel-room TV filled with the same image, as the director cut to it. “Look at this,” said Fawcett’s voice.

“That’s the one they’re calling three-dash-eleven, isn’t it?” said Koppel. “The eleventh picture from the third group of signals the Tailiens sent.”

“That’s right. Now, what do you see?”

The TV image changed back to a two-shot of Koppel and Fawcett, both looking at their own monitor. “It’s the Tailien head,” said Koppel. And indeed it was, drawn out like an alligator’s.

“Look carefully at the mouth,” said Fawcett.

Koppel shook his head. “I’m sorry; I’m not getting it.”

“That’s not a picture of the head, you know. It’s a picture of the Tailien cranium—the skull.”

“Yes?”

“It’s all one bone,” said Fawcett triumphantly. “There’s no separate mandible, no movable jaw. The mouth is just a boomerang-shaped opening in a solid head.”

Koppel frowned. “So you’re saying they couldn’t articulate? I guess it would be hard to talk without a hinged jaw.” He nodded. “No talking, no radio.”

“No, it’s not the ability to make sounds that depends on the advent of jaws. It’s the ability to hear sounds, or, at least, to hear them clearly and distinctly.”

Koppel waited for Fawcett to go on. “I’ve got TMJ—temporomandibular-joint syndrome,” said Fawcett, tapping his temple. “Discomfort where the jaw articulates with the temporal bone; it’s pretty common. Well, last winter, I had an infection in my ear canal—’swimmer’s ear,’ they called it. Except I didn’t know it for the longest time; I thought the pain was from my TMJ. Why? Because our ears are located right over our jaw joints—and that’s no coincidence. The small bones in our inner ear—the hammer, the anvil, and the stirrup—make our acute hearing possible, and they exist precisely because the skull splits there into the cranium and the jaw. Our earliest vertebrate ancestors were jawless fish—fish with heads very much like the Tailiens still seem to have, consisting of one solid piece of bone.”

Koppel was coming up to speed. “So … so, what? They take in soft food through permanently open mouths? No chewing?”

“Perhaps,” said Fawcett. “Or maybe that slit that runs down their torsos is a feeding orifice. But, either way, I’m willing to bet that they don’t depend on sound for communication.”

Darren worked with an illustrator from the Las Vegas Review-Journal and a doctor from the UNLV Medical Center coding a series of human-anatomy diagrams, but no one quite knew how to send them. It would take more than a day of flashing the city’s lights on and off—the power could only be cycled so quickly—to send even one of these high-resolution images, and the casinos wouldn’t stand for it. Every minute the power was off cost them tens of thousands of dollars in betting revenues.

But, before they’d figured out how to reply, a new set of messages—batch number four—arrived from the Tailiens.

Palm-Up-Middle-Fingers-Splayed personally supervised the sending of the next messages, since he’d been the one who had coded them. They were designed to convey a series of simple multiple-choice questions. The messages consisted of 23 rows of 79 columns, much smaller than the anatomical charts. Fist-Held-Sideways had opined that bandwidth might be a problem for the third planet in sending similar messages, which is presumably why no response had yet been received.

The top part of each message showed a simple math problem, and the bottom part showed three possible answers, one of which was correct. The boxes containing these answers were labeled, from left to right, with one pixel, two pixels, and three pixels respectively in their upper right-hand corners.

Palm-Up-Middle-Fingers-Splayed, Fist-Held-Sideways, and the rest awaited the answers from the third planet; nothing less than a perfect score on the test would be morally acceptable before they asked the most important question of all.

The aliens seemed to have no trouble reading the flashing of Las Vegas’s lights, and so the responses to the math problems were sent by that city winking itself on and off. Many of the hundred thousand people who had come to Nevada to be part of the first signaling effort were still in town, thrilled that an actual dialogue between humans and aliens seemed to be opening up.

Fortunately for the croupiers and pit bosses, the math problems only took seconds to reply to; all that had to be sent was the number of the box containing the correct answer: one flash, two flashes, or three flashes.

“There’s no doubt,” signed Palm-Up-Middle-Fingers-Splayed to Captain Curling-Sixth-Finger, “that the aliens understand our syntax. They clearly know how to give the correct response to a multiple-choice question—and they got all the answers right, even the one about division by zero.”