"They don't take as much power as the heaters do. It wouldn't help at all."
Tom twisted weightlessly and stared back at Earth. "Well just what the hell am I supposed to do?"
"Don't get excited," Jason's voice grated in his earphones. "We've calculated it all out. According to our figures, your suit will store enough heat during the day to last the night...."
"I nearly froze to death last night and the ship was heated most of the time!"
"It will get cold," Jason's voice answered calmly, "but you should be able to make it. Your own body warmth will be stored by the suit's insulation, and that will help somewhat. But you must not open the suit all night, not even to take off your helmet."
"And the oxygen?"
"You can take all the replacement cylinders from the ship and keep them at the satellite. The time you save by not having to go back and forth to the ship for fresh oxygen will give you about an hour's extra margin. You should be able to make it."
Tom nodded. "And of course I'm expected to work on the satellite right through the night."
"It will help you keep your mind off the cold. If we see that you're not going to make it—either because of the cold or the oxygen—we'll warn you and you can return to the settlement."
"Suppose I have enough oxygen to just finish the satellite, but if I do, I won't have enough to fly home. Will you warn me then?"