ers at D-9 rate, sir!"

Then, as the hiss of fuel pouring into the mighty engines of the ship
blended with the whine of the pumps, Tom snapped out a third order. "Cut
in take-off six yards!"

Receiving acknowledgment from below, he grasped the master blast-off
switch and watched the sweeping hand of the astral chronometer.

"Stand by to raise ship!" he yelled. "Blast off
minus--five--four--three--two--one--_zero_!"

He pulled the switch.

Slowly, the rockets blasting evenly, the giant ship lifted itself free
of the ground. Then, gaining speed, it began rocketing away from the
Earth. Like a giant shining bullet, the great spaceship blasted through
the dark void of space, her nose pointed to the distant misty planet of
Venus.

Once again Tom Corbett and his unit-mates had embarked on a mission for
the Solar Guard.

CHAPTER 2

"Stand by for touchdown!" bellowed Captain Strong's voice on the big
spaceship's intercom.

"Control deck standing by," replied Tom.

"Corbett," Strong continued, "you may take her down as soon as you get
clearance from Venusport traffic control."

Tom acknowledged the order with a brisk "Aye, sir! In a few moments he
received permission to touch down on the newly colonized planet. Then,
turning his attention to the control board, he requested a
ground-approach check from Roger.

"About two miles to touchdown, Tom," reported Roger from the radar
bridge. "Trajectory clear!"

"O.K., Roger," said Tom. Glancing quickly at the air speed and rocket
thrust indicators, he flipped a switch and sang out, "Power deck, reduce
thrust on main drive rockets to minimum!"

"Got ya, Tom," boomed Astro.

"Closing in fast, sir," said Tom to Strong, who had come up from below
and now stood at the cadet's shoulder watching as Tom maneuvered the big
ship through the Venusian atmosphere, his keen eyes sweeping the great
panel of recording gauges and dials.

"One thousand feet to touchdown," intoned Roger from the radar bridge.

Reacting swiftly, Tom adjusted several levers, then picking up the
intercom microphone, he threw a switch and yelled, "Power deck! Full
braking thrust!"

Deep inside the _Polaris_, Astro, who tended the mighty rocket power
plant with loving care, eased home the sensitive control mechanism,
applying even pressure to the braking rockets.

As the giant spaceship settled smoothly to within a few feet of the
surface of the concrete spaceport, Tom threw the master switch t