He stopped, but the thirty-year-old prodigy, Russell Clyde, took up the story. "By nova, we mean that the Sun will literally explode. It will flame up, burst to many times its present size. Such an explosion will burn Earth to cinders, render all the planets inside the orbit of Jupiter uninhabitable, scorch their atmospheres, dissolve their waters into steam, and make them lifeless flaming deserts. We have seen other stars turn nova. We have measured their explosions. We know just about what age and stability inside a sun is necessary to cause this. And we fear that the danger of our own Sun doing so is great--if the Sun-tapping is not stopped." Everyone at the table was silent. Burl was stunned. Finally he caught his breath. "But how can we stop it? We can't get to all the planets in time. Our rockets are not ready--and rocketships would be too slow. Why it would take two years for rocketships to reach Mars, if the expedition were ready now ... and I understand that it will be another ten years before Operation Mars is even attempted." General Shrove nodded. "That is correct. Our rocket engineering is not yet advanced enough to allow us to take such emergency action. We are still only just over the doorstep of interplanetary flight--and our enemies, whoever they may be, are obviously far advanced. But, as you will see, we are not entirely without hope. Colonel Lockhart, will you tell them about Project A-G?" All eyes turned to Lockhart, who was a short, stocky man in civilian clothes. Burl realized that this man had been a colonel at one time, but remembered now that he had taken a post with one of the largest aviation companies after leaving the service. Lockhart turned cold gray eyes directly to Burl. "We have in my company's experimental grounds one virtually untested vessel which may be able to make a flight to Mars, or any other planet, in the time allowed. This is the craft we refer to as A-G 17, the seventeenth such experiment, and the first to succeed. It is powered by an entirely new method of flight, the force of anti-gravity."