make it. Once
inside the asteroids, they would never find him.

Glancing around the few indicators on the control board of the small
vessel, Tom's smile changed to a grimace of sudden terror. The jet boat
had not been refueled after their raid on the jet liner. There was less
than three days' oxygen remaining in the tanks. In three days the jet
boat would become an airless shell. A vacuum no different than the cold
silent void of space!

CHAPTER 15

"What's our position, Roger?" Captain Strong called into the intercom.

"Space quadrant B, section twenty-three, sir," replied Roger from the
radar bridge. "But I can't see a thing on the radar. That static flash
Tom sent out is scrambling everything."

"But you're sure this is our position?"

"Yes, sir. I checked it three times."

"All right, then," said Strong grimly. "There's only one thing to do.
We're too near the asteroid belt to use the _Polaris_ without radar, so
we'll search in jet boats. Astro! We're parking right here! Give me full
braking rockets and secure the power deck. Then prepare the jet boats
for flight."

"Aye, aye, sir," came the reply from the Venusian.

The ship bucked under the tremendous power of the braking rockets and
came to a dead stop in space. Strong dashed up the ladder to the radar
bridge where Roger was still hunched before the radar scanner.

"Any chance of switching the scanner to another frequency and offsetting
the effects of the static, Roger?" asked the Solar Guard captain.

Roger shook his head. "I don't think so, sir. The interference would
have to be eliminated at its source."

"Well," sighed Strong, "to go looking for Tom without the help of radar
would be like looking for an air bubble in the ammonia clouds of
Jupiter. And we don't even know if he's still aboard the _Avenger_ or
not!"

"You know, sir," said Roger speculatively, "I've been thinking. I might
be able to get a fix on this interference."

"A fix? How?"

"By blanking out the radar range, so that it would only work at one
point of the compass at one time, then testing each heading separately
until the flash appears. When it does, we'd at least know in which
direction to blast off and trail Coxine.

"If you can do that, Roger," exclaimed Strong, "it would take us right
into Coxine's lap! Do you think you can work it?"

"I can try, sir."

"All right, then," decided Strong. "Astro and I will take the jet boats
and go looking around. Meantime