"Just received a report from the University of Venus, sir!" said the young officer. "There's been no volcanic activity on Venus in the last ten years serious enough to create such a cloud."
Strong waited for the professor's reaction, but the elderly man was already entering the air lock. Before Strong and Hawks could catch up to him, the air-lock hatch slammed closed.
"Hey," exclaimed Strong, "what does he think he's doing?"
"Don't worry about it, Steve," replied Hawks. "He probably forgot we were out here with him, he's so concerned about this dirt. We'll just have to wait until he's out of the air lock."
The Solar Guard officer nodded, then looked around him at the thick black cloud that enveloped the ship. "Well," he said, "one of the professor's theories has been knocked out."
"Yes," replied Hawks. "Which means this stuff is either the remains of a large asteroid or—"
"The third possibility," finished Strong, "which the professor never explained."
Suddenly the air-lock hatch opened again and the two spacemen stepped inside. Closing the hatch behind them, they waited until the pressure was built up again to equal that of the ship, and then they removed their helmets and space suits.