Robert Heinlein - The Past Through Tomorrow

Lazarus said regretfully, "Had to vector, Andy." Slayton Ford said nothing but looked worried.

"Yes, I know. But why?' Libby was already strapping himself against the copilot's couch while studying the astrogational situation.

"Red lights on the screen." Lazarus described the display, giving coordinates and relative vectors.

Libby nodded thoughtfully. "Naval craft. No commercial vessels would be in such trajectories. A minelaying bracket."

"That's what I figured. I didn't have time to consult you; I had to use enough mile-seconds to be sure they wouldn't have boost enough to reposition on us."

"Yes, you had to." Libby looked worried. "I thought we were free of any possible Naval interference."

"They're not ours," put in Slayton Ford. "They can't be ours no matter what orders have been given since I-uh, since I left. They must be Venerian craft."

"Yeah," agreed Lazarus, "they must be. Your pal, the new Administrator, hollered to Venus for help and they gave it to him-just a friendly gesture of interplanetary good will."

Libby was hardly listening. He was examining data and processing it through the calculator inside his skull. "Lazarus... this new orbit isn't too good."

"I know," Lazarus agreed sadly. "I had to duck... so I ducked the only direction they left open to me-closer to the Sun."

"Too close, perhaps."

The Sun is not a large star, nor is it very hot. But it is hot with reference to men, hot enough to strike them down dead if they are careless about tropic noonday ninety-two million miles away from it, hot enough that we who are reared under its rays nevertheless dare not look directly at it.

At a distance of two and a half million miles the Sun beats out with a flare fourteen hundred times as bright as the worst ever endured in Death Valley, the Sahara, or Aden. Such radiance would not be perceived as heat or light; it would be death more sudden than the full power of a blaster. The Sun is a hydrogen bomb, a naturally occurring one; the New Frontiers was skirting the limits of its circle of total destruction.

It was hot inside the ship. The Families were protected against instant radiant death by the armored walls but the air temperature continued to mount. They were relieved of the misery of free fall but they were doubly uncomfortable, both from heat and from the fact that the bulkheads slanted crazily; there was no level place to stand or lie, The ship was both spinning on its axis and accelerating now; it was never intended to do both at once and the addition of the two accelerations, angular and linear, met "down" the direction where outer and after bulkheads met. The ship was being spun through necessity to permit some of the impinging radiant energy to re-radiate on the "cold" side. The forward acceleration was equally from necessity, a forlorn-hope maneuver to pass the Sun as far out as possible and as fast as possible, in order to spend least time at perihelion, the point of closest approach.

It was hot in the control room. Even Lazarus had voluntarily shed his kilt and shucked down to Venus styles. Metal was hot to the touch. On the great stellarium screen an enormous circle of blackness marked where the Sun's disc should have been; the receptors had cut out automatically at such a ridicubus demand.

Lazarus repeated Libby's last words. "'Thirty-seven minutes to perihelion.' We can't take it, Andy. The ship can't take it."

"I know. I never intended us top this close."

"Of course you didn't. Maybe I shouldn't have maneuvered. Maybe we would have missed the mines anyway. Oh, well-" Lazarus squared his shoulders and filed it with the might-have-beens. "It looks to me, son, about time to try out your gadget." He poked a thumb at Libby's uncouth-looking "space drive." "You say that all you have to do is to hook up that one connection?"

"That is what is intended. Attach that one lead to any portion of the mass to be affected. Of course I don't really know that it will work," Libby admitted. "There is no way to test it."

"Suppose it doesn't?'

"There are three possibilities." Libby answered methodically. "In the first place, nothing may happen."

"In which case we fry."

"In the second place, we and the ship may cease to exist as mattei as we know it."

"Dead, you mean. But probably a pleasanter way."

"I suppose so. I don't know what death is. In the third place, if my hypotheses are correct, we will recede from the Sun at a speed just under that of light."

Lazarus eyed the gadget and wiped sweat from his shoulders. "It's getting hotter, Andy. Hook it up-and it has better be good!"

Andy hooked it up.

"Go ahead," urged Lazarus. "Push the button, throw the switch, cut the beam. Make it march."

"I have," Libby insisted. "Look at the Sun."

"Huh? Oh!"

The great circle of blackness which had marked the position of the Sun on the star-speckled stellarium was shrinking rapidly. In a dozen heartbeats it lost half its diameter; twenty seconds later it had dwindled to a quarter of its original width.

"It worked," Lazarus said softly. "Look at it, Slayton! Sign me up as a purple baboon-it worked!"

"I rather thought it would," Libby answered seriously. "It should, you know."

"Hmm- That may be evident to you, Andy. It's not to me. How fast are we going?"

"Relative to what?"

"Uh, relative to the Sun."

"I haven't had opportunity to measure it, but it seems to be just under the speed of light. It can't be greater."

"Why not? Aside from theoretical considerations."

"We still see." Libby pointed at the stellarium bowl.

"Yeah, so we do," Lazarus mused. "Hey! We shouldn't be able to. I ought to doppler out."

Libby looked blank, then smiled. "But it dopplers right back in. Over on that side, toward the Sun, we're seeing by short radiations stretched to visibility. On the opposite side we're picking up something around radio wavelengths dopplered down to light."

"And in between?"

"Quit pulling my leg, Lazarus. I'm sure you can work out relatively vector additions quite as well as I can."

"You work it out," Lazarus said firmly. "I'm just going to sit here and admire it. Eh, Slayton?"

"Yes. Yes indeed."

Libby smiled politely. "We might as well quit wasting mass on the main drive." He sounded the warner, then cut the drive. "Now we can return to normal conditions." He started to disconnect his gadget.

Lazarus said hastily, "Hold it, Andy! We aren't even outside the orbit of Mercury yet. Why put on the brakes?"

'Why, this won't stop us. We have acquired velocity; we will keep it."

Lazarus pulled at his cheek and stared. "Ordinarily I would agree with you. First Law of Motion. But with this pseudospeed I'm not so sure. We got it for nothing and we haven't paid for it-in energy, I mean. You seem to have declared a holiday with respect to inertia; when the holiday is over, won't all that free speed go back where it came from?"

"I don't think so," Libby answered. "Our velocity isn't 'pseudo' anything; it's as real as velocity can be. You are attempting to apply verbal anthropomorphic logic to a field in which it is not pertinent. You would not expect us to be transported instantaneously back to the lower gravitational potential from which we started, would you?"

"Back to where you hooked in your space drive? No, we've moved."

"And we'll keep on moving. Our newly acquired gravitational potential energy of greater height above the Sun is no more real than our present kinetic energy of velocity. They both exist."

Lazarus looked baffled. The expression did not suit him. '~I guess you've got me, Andy. No matter how I slice it, we seemed to have picked up energy from somewhere. But where? When I went to school, they taught me to honor the Flag, vote the straight party ticket, and believe in the law of conservation of energy. Seems like you've violated it. How about it?"