"It's a cinch they'll take the Polaris over," explained Tom. "She's fast and she's got six-inch blasters."
"I get it!" yelped Astro. "We plant the beacon on the Polaris, and when they take her over, the signal will be going out all the time." Astro paused. "But wait a minute. They'll be sure to search the ship first!"
"First things first, Astro," answered Tom. "Roger, can you make the beacon?"
"Yeah," said Roger, "but it'll take me at least a half hour!"
"You've got to finish it faster than that!" Tom insisted.
"I can't, Tom. I just can't."
"All right, then we'll have to stall as best we can. Get to work. Meantime, Astro and I will find a place to hide it. How big do you think it'll be?"
There was a momentary pause and then Roger replied, "No smaller than six inches. About like a shoe box."
"Could you make it three inches thick, and longer, instead of box-shaped?"
Roger hesitated again. "Yeah, I guess so. Why?"