"Attention! Attention! Identify yourselves immediately!" The voice from the Ganymede traffic-control tower came over the audioceiver again. Coxine's face twisted into a half-smile.
"Well, Corbett, do I get the signal or don't I?"
"Tell them you're a Solar Guard armed freighter." Tom's voice was low. "You're assigned to operation 'Vista.'"
"Vista?" said Coxine excitedly. "Is that the code word? Vista?"
"Yes," said Tom. "Now open the valve!"
Coxine gave the valve a number of turns in the opposite direction and jumped to the teleceiver. He flipped the key open and called Wallace aboard the Polaris. "When they ask you for identification, tell them you're working on operation Vista. That's the key word. Vista!"
"Right!" answered Wallace.
Coxine then turned to the audioceiver and spoke in confident, assured tones. "Attention, Ganymede traffic control! This is armed freighter Samson, assigned on project Vista. Request clearance for approach and touchdown on Ganymede spaceport!"
"You are properly identified, Samson," replied Ganymede. "Proceed on your present course. End transmission."
"End transmission!" roared Coxine triumphantly.