The Door

"I have considered that possibility. In the vacuum of Space there are many things possible which would not happen under the influence of gravity. I cannot rule out the crystalline theory,"

"Natural crystals rarely occur on such a grand scale," said Paul. "Is it possible that some earlier mission from Earth has left this 'thing' here and forgotten it?"

Phillip tapped the wall and took a sheet of paper from a drawer which slid silently out to him.

"Computer read-out," he said. "I already thought of that. No record of human activity in this area, apart from surveys. No dumping of machines, no crashed rockets, nothing."

"So we've got three choices," said Ralph, "Its natural stuff, or its unnatural stuff."

"You said three choices," said Paul.

"Number three isn't worth thinking about. I just threw it in because we have to be logical. The stuff might have been left or put there by some other intelligence, but well, that's untenable. It just had to be included."

"That one belongs with the fairies!" laughed Paul.

"I know," said Ralph, dryly.

"So," said Phillip, "If what we've found is a natural substance, it might be very useful... once we figure out what it is. A material that strong and flat could be very valuable. I'll check the computer for past surveys and see if anything was missed." The men waited while he tapped in some entries and did a search. The monitor flicked. A survey map appeared, followed by several overlays, in different colors. "Here it is" said Phillip," Large deposit, possibly iron ore. Unverified". He looked at the date and whistled.

"Ten years ago! You'd think they would have done a better job than that!"

"Come off it," said Ralph, "There are thousands of spots like that on the moon. You can't expect them to check them all!"

Phillip ignored the light mockery and continued to search through the visuals. "I know where we'll be tomorrow," said John, leaning back with a sigh.

"First thing" said Phillip. "Get the maintenance crew to put some new teeth on the machines. Ralph?"