hole, saw with satisfaction it was in almost perfect
alignment, and ordered the bomb placed. He bent over the edge of the hole
and watched Trudeau pay out wire while Dominico pushed the bomb to the
bottom. The Italian made a last minute check, then called to Rip. "Ready,
sir."

He dropped into the hole and inspected the connections himself, then
personally pulled the safety lever. The bomb was armed. When the timer
acted, it would go off.

Back at ground level, he turned up his communicator. "Koa, is everything
ready at the boat?"

"Ready, sir."

The Planeteers had already carried away the torch and its fuel and oxygen
supplies. The area was clear of pieces of thorium.

Rip announced, "We're setting the explosion for ten minutes." He leaned
over the timer, which rested near the lip of the hole, took the dial
control in his glove and turned it to position ten. He held it long enough
to glance at his chronometer and say, "Starting now!" Then he let it go.

Wasting no time, but not hurrying, he and Dominico returned to the landing
boat. The Planeteers were already aboard, except for Koa, who stood by to
cast off the remaining tie line. Rip stepped inside and counted the men.
All present. He ordered, "Cast off." As Koa did so and stepped aboard, he
added, "Pilot, take off. Straight up."

The landing boat rose from the asteroid. Rip counted the men again, just
to be sure. The boat seemed a little crowded, but that was because the
rear compartment took up quite a bit of room.

Rip watched his chronometer. They had plenty of time. When the boat
reached a point about ten miles above the asteroid, he ordered, "Stern
tube." The boat moved at an angle. He let it go until a sight at the stars
showed they were about in the right position, 90 degrees from the line of
blast and where they would be behind the asteroid as it moved toward the
new course.

He looked at his chronometer again. "Two minutes. Line up at the side if
you want to watch, but darken your helmets to full protection. This thing
will light up like nothing you've ever seen before."

It was a good thing space cruisers depended on their radar and not on
sight, he thought. Usually spacemen opened up visual ports only when
landing or taking a star sight for an astro-plot. The clear plastic of the
domes had to be shielded from chance meteors. Besides, radar screens were
more dependable than eyes, even though they could pick up only solid
objects. If the Consops