s is the hard part now. I don't
mind dying, if I have to. But I don't want to.

MAYBE YOU WON'T DIE, said a voice. Yes, and maybe I will. I hope that
my son understands. I hope he sees that I have no choice. BUT YOU
HAVE A CHOICE. Do I? If there is a choice then I don't see it. Not
without surrendering all that we have worked for. No. I cannot go
back.

His son entered the room, followed by Stein and Alexander Dimitriev,
his chief engineer. At his gesture they were seated at the table
across from him.

"Thomas, Alexander. Now we are come to the hard part: how to detonate
safely and accurately. As you know, in this, timing is everything.
Everything. If we miss by only a few seconds, we doom the planet to
extinction."

"Is it true that you intend to remain behind?" said Dimitriev, "and
detonate the bombs yourself, from no greater distance than a thousand
kilometers?"

"Father!" YOU MUST UNDERSTAND, LEON.

"Before I say yes or no, let us look at the alternatives. That is why
you are here. I must know that you stand behind me."

"We could blow them by radio control." His son.

"No. With the static storms this heavy and unpredictable, they could
detonate too soon, or not at all."

"What about a laser-triggered mechanism above ground?" asked Dimitriev.
"A fast moving ship could activate it, then be gone." Dobrynin opened
his hand toward Stein.

"I'm afraid that's not possible," he conceded. "To avoid cloud cover
and volcanic discharge the ship would have to fly very high. And the
way the upper atmosphere refracts light, even laser is not a sure
thing. And also, there is the problem of the gravity beam itself,
distorting the path of the ship."

Dimitriev turned away.

"Alexander, Leon. Listen to me. There is only one other chance that I
see, and it is not a good one. We could build the laser-trigger upon a
high tower, allowing me to activate it from the ground at a greater
distance. But I am not sure we could construct such a tower in time.
And also, it would cost more lives." He looked at his son. "Or I
could detonate the bombs myself, safely and surely, by cable from
Leopold Station. I wish there was another way."

"But why does it have to be you? You are needed---" His son broke off.

"Who would you have me send instead? I am most qualified, except
perhaps for Stein. And this....." He spoke now with difficulty.
"This is my home. It is everything I have worked for. I