ore it reached them.

"Fire bomb," Koa muttered.

Rip nodded. He had recognized it. The Planeteers were trained in the use
of fire bombs, tanks of chemicals that burned even in an airless world.
They were equipped with simple jets for use in space.

The snapper-boats drew off, back toward the _Scorpius_. Rip watched,
searching for some reason for their actions. Then one of the boats
pulled away from the others. It returned to the asteroid, with stern jet
burning fitfully.

"Is he landing?" Koa asked.

Rip didn't know. The snapper-boat was moving slowly enough to make a
landing.

Directly above the asteroid it changed direction, circled, and returned
over their heads. Rip could almost have picked it off with a pistol shot.
Santos could have blasted it into space dust with one rocket.

The snapper-boat changed direction, and for a fraction of a second stern
and side tubes "fought" each other, making the boat yaw wildly. Then it
straightened out on a new course.

Koa exclaimed, "That's a drone!"

Rip got it then. A pilotless snapper-boat! That's why its actions were a
little uneven. Only one thing could explain its deliberate slowness. It
was bait. The _Scorpius_ had sent piloted snapper-boats over the asteroid
at high speed, crisscrossing in order to cover the thorium world
completely, expecting to have the unknown rocketeer fire at them. Then a
fire bomb had been dropped as a further means of getting the asteroid to
fire. But no rockets had been fired from the asteroid, so the pilot in
control of the drone had sent it at low speed, a perfect target.

That meant O'Brine wasn't sure of what was going on. He must have seen
the blip on his screen as the Connie cruiser flamed off, Kip reasoned.
But the commander probably suspected that the Connies had overcome
the Planeteers and were in control of the asteroid. He had sent the
snapper-boats to try to draw fire, in an attempt to find out more surely
whether Planeteers or Connies had the thorium rock.

"The _Scorpius_ doesn't know what's going on," Rip told his Planeteers.
"O'Brine didn't know the cruiser was waiting to ambush him, so the rocket
we fired made him think the Connies had taken us over."

He put himself in O'Brine's place. What would his next step be? The
snapper-boats hadn't drawn fire, even when a drone was sent over at low
speed. The next thing would be to send a piloted boat over slowly enough
to take a look.

Rip hoped O'Brine would hurry. Ther