"Because they're opaque," said Archer patiently, "and the aura is so faint that your cranium alone probably wouldn't give off enough to be visible. Personally, I'm going to strip to the waist. I'd be inclined to strip further, if it weren't for the fact that some of those crawling things out there are about as deadly as the virus."
In silence, the three men climbed down from the airlock, their flashlights cutting holes in the thick darkness. Faria was a moonless planet, and the hour was late.
Under the watchful eye of Stokely, Archer walked clear of the retractable landing supports and shone his flashlight about the small level area in which the ship was fairly centered. He held the beam steady on an outcropping of rock about 40 feet away.
"There's a good background for you, Stokely. It faces the lock, and I imagine you'll want to do the same."
He swung the flashlight slowly around. There were several piles of boulders standing about, and Archer indicated two of them, each about 120 degrees from the first.
"Evans and I can take those two positions. That way we'll form a triangle, each of us about 40 feet from the ship, and in plain sight of the others—that is, if we develop that fatal glow. In any case, Stokely, I think you can depend on us staying put until we find out, since—"
"And then what happens?" Stokely demanded impatiently. "How do we find out—without trusting each other? The whole set-up sounds silly to me!"
"It's my life, too," Archer reminded him. "And in case you're in any doubt, I don't trust you, either. Here's the plan: As you know, all of us were exposed within a very few minutes of each other. That means, according to our late friend, the doctor, that in ten to 12 minutes from now—perhaps a few minutes longer—one or more of us should show the symptomatic aura.
"Now there's the point: one or more of us. There's an excellent chance we won't all show it. Allowing an adequate margin, the next 20 minutes should reveal who has the infection and who hasn't. I propose that at the end of that time each of us in turn announces, not which of the others shows it but simply whether he sees the aura at all. He doesn't tell whether one or both of the others shows it, but merely whether at least one does."