The machine men took the professor's body from his rocket satellite and recalled his brain to life in order to learn his story. They placed the brain in one of the mechanical bodies. The professor's astonishment on his revival can be imagined better than described. When he came to a full realization of what had actually happened, he told them his story and of the past glories of the earth up to the point when he had died. He found that his revival made him the last living creature of the earth. With the machine men he visited the strangely changed surface of his home planet. The Zoromes told him of their eternal adventures from world to world and asked him to join them. There was nothing on the now-lifeless Earth to keep him there--so he joined the machine men in their cosmic flight from system to system, exploring new planets and strange creatures of varying degrees of intelligence. He came to be known among the Zoromes as 21MM392, and after their return to Zor he was given joint command with 744U-21 of a new expedition into space. Since last leaving Zor, they had explored many curious worlds, and their adventures had been strange ones, often perilous. They were now entering another system of worlds. Already, they had passed several of the outer planets on their side of the sun. They were barren and cold, too far from the sun to support life. CHAPTER TWO Heralds of Doom "A planet or planetoid just off our course, 41C-98 reports," said 744U-21 to the professor. "We are now heading that way to discover what it may be. 41C-98 reports several peculiarities. For one thing, the sunshine strikes very dull against it, and for its apparent bulk our proximity detectors show a surprising lack of density." As they moved nearer the mysterious body, they discovered that it was neither planet nor asteroid, nor did it move on an orbit. On the contrary, it pursued a course directly at right angles to an orbit. It was heading sunward. The character of the celestial wanderer and its strange lack of density became understood when the spaceship of Zor approached close enough to reveal it as a meteoric swarm consisting of dust and cosmic debris. Many of the chunks were several miles in diameter. The professor's quick estimate placed the diameter of the swarm at seven thousand miles. Rapid observations and computations were made. Growing suspicions of the machine men were verified. The mass was heading into the sun at a speed of several miles per second. "You know what that means," said the professor, turning to those about him. "Yes--a nova--an exploding star!" "I never saw but one at close range during my entire existence as a machine man," said 6W-438.