to the door,
tightened their face plates, and forced open the exit. There was a rush
of air as the ship exhausted its atmosphere. Then, one by one, they
stepped onto the bleak surface of the Sun's farthest planet.

"I feel peculiar," whispered Burl. "This planet reminds me of
something."

"I have the feeling I've been here before," Russ said slowly.

Burl felt an odd chill. "Yes, that's it!"

Haines grumbled. "I know what you mean. I can make a guess. We've never
really been the right weight since we left Earth. Even under
acceleration there were differences one way or the other. But I feel now
exactly as I did on Earth. That's what gives you the odd sensation of
return."

The two younger men realized Haines was right. For the first time since
they had left their home world, they were on a planet whose gravity was
normal to them. It felt good and yet it felt--in these fearful
surroundings--disconcerting.

Above them was the familiar black, unyielding sky of outer space. No
breath of air moved. Yet somehow the scene resembled Earth. "It's like a
black-and-white photo of a Terrestrial landscape," said Burl.

There was a field, some hills, a tiny frozen creek and the dark shapes
of rounded mountains in the distance. All without color except for the
cold, faint glow of the star that was the Sun.

A thin layer of cosmic dust lay over the surface, such as would be found
on any airless world. Russ scooped beneath it and came up with a hard
chip.

He squeezed it between his gauntleted fingers. It cracked and broke into
powder. He whistled softly. "You know what this feels and looks like?"
he said as they came close to the frozen creek on the little hillside.
"It feels like dirt--common, Earthly dirt. Like soil. And you know
what ... I can already tell you one of Pluto's secrets."

They stopped at the creek. It was a layer of frozen crystalline gases.
Haines pushed the alpenstock he was carrying into it and scraped away
the gas crystals. "I think I can guess," he said, "and I'll bet there is
ice under this gas."

"Pluto was once a warm world with a thick atmosphere," said
Russ. "Notice the rounded hills and the worn away peaks of the
mountains. Those are old mountains--weather-beaten. This hill is
round--weather-beaten. This creek, those rivers of frozen gas--they
follow beds that could only be made by real rivers of warm water. The
soil that lies beneath this dust--it could only happen on a world that
knew night