ro's
or Roger's questions, he jammed his foot down hard on the acceleration
lever, sending the tiny ship blasting away from the _Polaris_.

Not until they were two miles away from the stricken rocket ship did
Connel bring the craft to a stop. He turned and gazed helplessly at the
gleaming hull of the _Polaris_.

"So they know," he said bitterly. "They're trying to stop me from even
reaching Venus."

The three cadets looked at each other and then at the burly spaceman,
bewilderment in their eyes.

"What's this all about, sir?" Roger finally asked.

"I'm not at liberty to tell you, Manning," replied Connel. "Though I
want to thank you for your quick thinking. How did you happen to
discover the bomb?"

"I was sighting on Regulus for a position check and Regulus was dead
astern, so when I swung the periscope scanner around, I spotted that
thing stuck to the fin. I didn't bother to think about it, I just
yelled."

[Illustration]

"Glad you did," nodded Connel and turned to stare at the _Polaris_
again. "Now I'm afraid we'll just have to wait until that bomb goes
off."

"Isn't there anything we can do?" asked Tom.

"Not a blasted thing," replied Connel grimly. "Thank the universe we
shut off all power. If that baby had blown while the reactant was
feeding into the firing chambers, we'd have wound up a big splash of
nothing."

"This way," commented Astro sourly, "it'll just blast a hole in the side
of the ship."

"We might be able to repair that," said Tom hopefully.

"There she goes!" shouted Roger.

[Illustration]

Staring out the windshield, they saw a sudden blinding flash of light
appear over the stern section of the _Polaris_, a white-hot blaze of
incandescence that made them flinch and crouch back.

"By the craters of Luna!" exclaimed Connel.

Before their eyes they saw the stabilizer fin melt and curl under the
intense heat of the bomb. There was no sound or shock wave in the vacuum
of space, but they all shuddered as though an overwhelming force had
swept over them. Within seconds the flash was gone and the _Polaris_ was
drifting in the cold blackness of space! The only outward damage visible
was the twisted stabilizer, but the boys realized that she must be a
shambles within.

"I guess we'll have to wait a while before we go back aboard. There
might be radioactivity around the hull," Roger remarked.

"I don't think so," said Tom. "The _Polaris_ was still coasting when we
left her. We cut o