the plateau of Howe’s H. He did not recognize them; they
conformed to none of the photographs he had memorized;
but they accepted his story readily enough. And he had not
needed to pretend exhaustion -Ganymede’s gravity was nor-
mal to him, but it had been a long trek and a longer climb.
He was surprised to find, nevertheless, that he had enjoyed
it. For the first time in his life he had walked unguarded,
either by men or by mechanisms, on a world where he felt
physically at home; a world without walls, a world where he
was essentially alone. The air was rich and pleasant, the
winds came from wherever they chose to blow, the tempera-
ture in the col was considerably below what had been allow-
able in the dome on the Moon, and there was sky all around
him, tinged with indigo and speckled with stars that twinkled
now and then.
He would have to be careful. It would be all too easy to
accept Ganymede as home. He had been warned against that,
but somehow he had failed to realize that the danger would
be not merely real, but seductive.
The young men took him swiftly the rest of the way to the
colony. They had been as incurious as they had been anony-
mous. Rullman was different. The look of stunned disbelief
on the scientist’s face, as Sweeney was led into his high-
ceilinged, rock-walled office, was so total as to be frightening.
He said: “What’s this!”
“We found him climbing the col. We thought he’d gotten
lost, but he says he belongs to the parent flight.”
“Impossible,” Rullman said. “Quite impossible.” And then