Biff’s feet hit the brakes of the sled and the runners chewed into the hard ice pack, shrieking, and bringing the sled to a skidding stop. The riders were slammed forward. Sue and Steve were dazed, but not hurt. When Steve’s mind cleared, he saw that Biff had thrown himself over in front of Sue and him to protect them. But in doing this, his helmet had thumped against the windshield. He was now slumped over and not moving.

“Sue!” Steve cried. “Biff is hurt!”

Just then they felt the shock of the explosion. It tilted the sled at an angle and dropped it down again with a hard jolt. The air was filled with flying chunks of ice. It looked like a hailstorm outside. The ice clattered against the windshield like stones. Sue and Steve were relieved when it finally stopped. But the explosion had left the ice sheet in front of them broken and choked with lumps of ice.

“Steve,” Sue moaned, “what are we going to do?”

Steve looked at Biff who was still not moving. He could see a big lump on Biff’s forehead where his head had struck the helmet, knocking him out. The children tried to revive their friend, but could not.

“We’ve got to get the sled to the ship ourselves, Sue!” her brother said. “Biff may need a doctor! Besides, I bet we’ve all missed our Thanksgiving dinner!”

“I won’t want any dinner if Biff is hurt badly!” Sue said tearfully.

At first it seemed like an impossible thing for a pair of twelve-year-olds to run the big sled. But Steve remembered how Biff had worked the controls and he believed he, too, could do it. He changed seats with the unconscious spaceman and tried the levers and buttons.

Presently the sled’s rockets began to pour fire out of the rear. But Steve couldn’t get the sled to move. He was afraid it had been damaged. Then Sue showed him a lever to push which she had remembered seeing Biff shove. As Steve worked it gently, the sled started off slowly.

“We’ll go slow,” Steve said, “and take it very easy.”