The group shook hands all around; then the young officers broke for the
door on the run. The Terra rocket was blasting off in five minutes, and
they were due to be on it.

Rip joined Flip Villa and they jumped on the high speed track that would
whisk them to Valve Two on the other side of the platform. Their gear was
already loaded. They had only to take seats on the rocket and their six
years on the space platform would be at an end.

"I wonder what it will be like to get back to high gravity?" Rip mused.
The centrifugal force of the spinning platform acted as artificial
gravity, but it was considerably less than earth's.

"We probably won't be able to walk straight until we get our earth-legs
back," Flip answered. "I wish I could stay in Colorado with you instead of
going back to Mexico City, Rip. We could have a lot of fun in eight
weeks."

Rip nodded. "Tough luck, Flip. But anyway, we have the same assignment."

Both Planeteers had been assigned to Special Order Squadron Four, which
was attached to the cruiser _Bolide_. The cruiser was in high space,
beyond the orbits of Jupiter and Saturn doing comet research.

They got off the track at Valve Two and stepped through into the rocket's
interior. Two seats just ahead of the fins were vacant and they slid into
them. Rip looked through the thick port beside him and saw the distinctive
blue glow of a nuclear drive cruiser sliding sternward toward the
platform.

"Wave your eye stalks at that job," Flip said admiringly. "Wonder what
it's doing here?"

The space platform was a refueling depot where conventional chemical fuel
rockets topped off their tanks before flaming for space. The newer nuclear
drive cruisers had no need to stop. Their atomic piles needed new neutron
sources only once in a few years.

The voice horn in the rocket cabin sounded. "The SCN _Scorpius_ is passing
Valve Two, landing at Valve Eight."

"I thought that ship was with Squadron One on Mercury," Rip recalled.
"Wonder why they pulled it back here?"

Flip had no chance to reply because the chief rocket officer took up his
station at the valve and began to call the roll. Rip answered to his name.

The rocket officer finished the roll, then announced: "Buttoning up in
twenty seconds. Blast off in forty-five. Don't bother with acceleration
harness. We'll fall free, with just enough flame going for control."

The ten-second warning bell sounded, and, before the bell had ceased, the
voic