He paused to jump over a shallow, six-foot-wide rift in the surface, a reminder of some eons-old Mercury-quake, perhaps, which could not heal over without wind and weather. He made the jump clumsily, the picture of an Earthman who, even on Mercury, stayed close to the artificial gravity of the Observatory Dome.
Bigman clicked his tongue disapprovingly at the sight. He and Lucky negotiated the jump with scarcely anything more than a lengthening of stride.
A quarter mile farther on, Mindes said abruptly, "We can see it from here, and just in time too."
He stopped, teetering forward, with arms outflung for balance. Bigman and Lucky halted with a small hop which kicked up a spurt of gravel.
Mindes's helmet flash went out. He was pointing. Lucky and Bigman put out their own lights and there, in the darkness, where Mindes had pointed, was a small, irregular splotch of white.
It was brilliant, a more burning sunshine than Lucky had ever seen on Earth.
"This is the best angle for seeing it," said Mindes. "It's the top of Black and White Mountain."
"Is that its name?" asked Bigman.
"That's right. You see why, don't you? It stands just far enough nightward of the Terminator… That's the boundary between the dark-side and the Sun-side."
"I know that," said Bigman indignantly. "You think I'm ignorant?"
"I'm just explaining. There's this little spot around the North Pole, and another around the South Pole, where the Terminator doesn't move much as Mercury circles the sun. Down at the Equator, now, the Terminator moves seven hundred miles in one direction for forty-four days and then seven hundred miles back in the next forty-four. Here it just moves half or mile or so altogether, which is why this is a good place for an observatory. The Sun and the stars stand still.
"Anyway, Black and White Mountain is just far enough away so that only the top half of it is lit up at most. Then, as the Sun creeps away, the light moves up the mountain slopes."
"And now," interposed Lucky, "only the peak is lit up."
"Only the top foot or two maybe, and that will be gone soon. It will be all dark for an Earth-day or two, and then the light starts coming back."
Even as he spoke the white splotch shrank to a dot that burned like a bright star.
The three men waited.
"Look away," advised Mindes, "so that your eyes get accustomed to darkness."
And after slow minutes he said, "All right, look back."
Lucky and Bigman did so and for a while saw nothing.
And then it was as though the landscape had turned bloody. Or a piece of it had, at any rate. First there was just the sensation of redness. Then it could be made out, a rugged mountain climbing up to a peak. The peak was brightly red now, the red deepening and fading as the eye traveled downward until all was black.
"What is it?" asked Bigman.
"The Sun," said Mindes, "has sunk just low enough now so that, from the mountain peak, all that remains above the horizon is the corona and the prominences. The prominences are jets of hydrogen gas that lift thousand of miles above the Sun's surface, and they're a bright red in color. Their light is there all the time, but ordinary sunlight drowns it out."
Again Lucky nodded. The prominences were again something which on Earth could be seen only during a total eclipse or with special instruments, thanks to the atmosphere.
"In fact," added Mindes in a low voice, "they call this 'the red ghost of the Sun.' "
"That's two ghosts," said Lucky suddenly, "a white one and a red one. Is it because of the ghosts that you carry a blaster, Mr. Mindes?"
Mindes shouted, "What?" Then, wildly, "What are you talking about?"
"I'm saying," said Lucky, "that it's time you told us why you really brought us out here. Not just for the sights, I'm sure, or you wouldn't carry a blaster on an empty, desolate planet."
It took a while for Mindes to answer. When he did, he said, "You're David Starr, aren't you?"
"That's right," said Lucky patiently.
"You're a member of the Council of Science. You're the man they call Lucky Starr."
Members of the Council of Science shunned publicity, and it was with a certain reluctance that Lucky said again, "That's right."
"Then I'm not wrong. You're one of their ace investigators, and you're here to investigate Project Light."
Lucky's lips thinned as they pressed together. He would much rather that were not so easily known. He said, "Maybe that's true, maybe it isn't. Why did you bring me here?"
"I know it's true, and I brought you here"-Mindes was panting-"to tell you the truth before the others could fill you-full of-lies."
"About what?"
"About the failures that have been haunting-I hate that word-the failures in Project Light."
"But you might have told me what you wanted to back at the Dome. Why bring me here?"
"For two reasons," said the engineer. His breathing continued rapid and difficult. "In the first place, they all think it's my fault. They think I can't pull the project through, that I'm wasting tax money. I wanted to get you away from them. Understand? I wanted to keep you from listening to them first."
"Why should they think it's your fault?"
"They think I'm too young."
"How old are you?"
"Twenty-two."
Lucky Starr, who wasn't very much older, said, "And your second reason?"
"I wanted you to get the feeling of Mercury. I wanted you to absorb the-the-- " He fell silent.
Lucky's suited figure stood straight and tall on Mercury's forbidding surface, and the metal of one shoulder caught and reflected the milky light of the corona, "the white ghost of the Sun."
He said, "Very well, Mindes, suppose I accept your statement that you are not responsible for failures in the project. Who is?"
The engineer's voice was a vague mutter at first. It coalesced gradually into words. "I don't know- At least… "
"I don't understand you," said Lucky.
"Look," said Mindes desperately, "I've investigated. I spent waking and sleeping periods trying to pinpoint the blame. I watched everybody's movements. I noted times when accidents took place, when there were breaks in the cables or when conversion plates were smashed. And one thing I'm sure of-- "
"Which is?"
"That nobody at the Dome can be directly responsible. Nobody. There are only about fifty people in the Dome, fifty-two to be exact, and the last six times something has gone wrong I've been able to account for each one. Nobody was anywhere near the scenes of the accidents." His voice had gone high-pitched.
Lucky said, "Then how do you account for the accidents? Mercury-quakes? Action of the Sun?"
"Ghosts!" cried the engineer wildly, flinging his arms about. "There's a white ghost and a red ghost. You've seen those. But there are two-legged ghosts too. I've seen them, but will anyone believe me?" He was almost incoherent. "I tell you… I tell you… "
Bigman said, "Ghosts! Are you nuts?"
At once Mindes screamed, "You don't believe me either. But I'll prove it. I'll blast the ghost. I'll blast the fools who won't believe me. I'll blast everyone. Everyone!"
With a harsh screech of laughter he had drawn his blaster, and with frenzied speed, before Bigman could move to stop him, he had aimed it at Lucky at point-blank range and squeezed its trigger. Its invisible field of disruption lashed out…
2. Mad or Sane?
It would have been the end of Lucky if he and Mindes had been on Earth.
Lucky had not missed the gathering madness in Mindes's voice. He had been waiting carefully for some break, some action to suit the violence of the engineer's hard-breathed sentences. Yet he had not entirely expected an outright assault with the blaster.