The red orb of the sun hung low above the horizon. It was a tired star, in the last stages of its life. One day the energy hoarded in its heart would falter, and the star would finally die. For now, it shed a feeble light and a meagre warmth on the world that orbited it, enough that life of a kind could continue to exist.

Two figures stood on a snow-covered plain, watching the sun set. They were not native to the world. No - these figures were human: hot-blooded and intelligent children of a younger (and warmer) world. Wisps of white breath emerged from under the hoods of their padded coats, and dispersed quickly in the cold air. From behind them came the screams and laughter of children at play, but their attention was focussed on the south-western sky.

Martha, a teacher and moulder of young minds, clapped her arms around her. It felt good and set her blood flowing. "The end of another year," she said. "We'll have to bring the children in soon."

Her companion, a visiting official from their distant homeworld, shivered. "I don't know how you can stand it here," he said. "This place is bleak enough as it is, but to spend almost a year inside? How can you stand it?"

Martha shrugged her shoulders, her gesture almost invisible under the padding of her coat. "We're used to it, I suppose. And we like each other's company. What do you do in winter?"

"I go to my family's villa down by the coast. It's warm all year round there. We spend the winter swimming and partying."

Martha smiled and bowed her head. "It's not so different to what we do. We exercise and we celebrate as well. It's just we have to do it inside, that's all."

The official gave Martha a pitying look. "You make it sound so functional: exercise, celebrate. There's no passion in those words, no energy."

"No passion?" Martha was shocked at the accusation. "Of course we have passion! Look." She pulled at the official's arm, turning him around to face the children. "There's our passion, right in front of you."

"Children everywhere play. It's what being a child is about. If you're telling me that your children aren't allowed to - "

"No!" Martha interrupted him. "Of course our children play. What kind of monsters do you think we are? How long are you here for?"

"Until my ship is ready to leave. Another six months - a quarter of your year."

Martha smiled. "Then you'll see exactly what our passion is like." She looked up at the wine dark sky. "Time to go!" she called out to the children. Then she took her companion by the arm, pulling him close to her. "Help me get them in before it starts to snow."

"Of course."