was going ten astro units a second. He
thought he knew why he had been chosen for the job. Word of the priceless
asteroid must have reached headquarters only a short time before he was
scheduled to leave the space platform. He could imagine the speed with
which the specialists at Terra base had acted. They had sent orders
instantly to the fastest cruiser in the area, the _Scorpius_, to stand by
for further instructions. Then their personnel machines must have whirred
rapidly, electronic brains searching for the nearest available Planeteer
officer with an astrophysics specialty and astrogation training.

He could imagine the reaction when the machine turned up the name of a
brand-new lieutenant. But the choice was logical enough. He knew that
most, if not all, of the Planeteer astrophysicists were either in high or
low space on special work. Chances are there was no astrophysicist nearer
than Ganymede. So the choice had fallen to him.

He had a mental image of the Terra base scientists feeding data into the
electronic brain, taking the results, and writing fast orders for the men
and supplies needed. If his estimate was correct, work at the Planeteer
base had been finished within an hour of the time word was received.

When they opened the cases brought aboard by the Martians, he would see
that the method of blasting the asteroid into a course for earth was all
figured out for him.

Rip was anxious to get at those cases. Not until he saw the method of
operation could he begin to figure his course. But there was no
possibility of getting at the stuff until brennschluss. He put the problem
out of his mind and concentrated on what his men were saying.

"... and he slugged into that asteroid going close to seven AU's," Santos
was saying. The little Filipino corporal shrugged expressively.

Rip recognized the story. It was about a supply ship, a chemical drive
rocket job that had blasted into an asteroid a few years before.

Private Dowst shrugged, too. "Too bad. High vack was waiting for him.
Nothing you can do when Old Man Nothing wants you."

Rip listened, interested. This was the talk of old space hands. They had
given the high vacuum of empty space a personality, calling it "high
vack," or "Old Man Nothing." With understandable fatalism, they
believed--or said they believed--that when high vacuum really wanted you,
there was nothing you could do.

Rip had come across an interesting bit of word knowledge. Spaceme