There is a time for doing and a time for going home. But where is home in an ever-changing universe?

"Lewis," Martha said. "I want to go home."

She didn't look at me. I followed her gaze to Earth, rising in the east.

It came up over the desert horizon, a clear, bright star at this distance. Right now it was the Morning Star. It wasn't long before dawn.

I looked back at Martha sitting quietly beside me with her shawl drawn tightly about her knees. She had waited to see it also, of course. It had become almost a ritual with us these last few years, staying up night after night to watch the earthrise.

She didn't say anything more. Even the gentle squeak of her rocking chair had fallen silent. Only her hands moved. I could see them trembling where they lay folded in her lap, trembling with emotion and tiredness and old age. I knew what she was thinking. After seventy years there can be no secrets.

We sat on the glassed-in veranda of our Martian home looking up at the Morning Star. To us it wasn't a point of light. It was the continents and oceans of Earth, the mountains and meadows and laughing streams of our childhood. We saw Earth still, though we had lived on Mars for almost sixty-six years.

"Lewis," Martha whispered softly. "It's very bright tonight, isn't it?"

"Yes," I said.

"It seems so near."

She sighed and drew the shawl higher about her waist.

"Only three months by rocket ship," she said. "We could be back home in three months, Lewis, if we went out on this week's run."

I nodded. For years we'd watched the rocket ships streak upward through the thin Martian atmosphere, and we'd envied the men who so casually travelled from world to world. But it had been a useless envy, something of which we rarely spoke.

Inside our veranda the air was cool and slightly moist. Earth air, perfumed with the scent of Earth roses. Yet we knew it was only illusion. Outside, just beyond the glass, the cold night air of Mars lay thin and alien and smelling of alkali. It seemed to me tonight that I could smell that ever-dry Martian dust, even here. I sighed, fumbling for my pipe.

"Lewis," Martha said, very softly.

"What is it?" I cupped my hands over the match flame.

"Nothing. It's just that I wish – I wish we could go home, right away. Home to Earth. I want to see it again, before we die."

"We'll go back," I said. "Next year for sure. We'll have enough money then."

She sighed. "Next year may be too late."

I looked over at her, startled. She'd never talked like that before. I started to protest, but the words died away before I could even speak them. She was right. Next year might indeed be too late.

Her work-coarsened hands were thin, too thin, and they never stopped shaking any more. Her body was a frail shadow of what it had once been. Even her voice was frail now.

She was old. We were both old. There wouldn't be many more Martian summers for us, nor many years of missing Earth.

"Why can't we go back this year, Lewis?"

She smiled at me almost apologetically. She knew the reason as well as I did.

"We can't," I said. "There's not enough money."

"There's enough for our tickets."

I'd explained all that to her before, too. Perhaps she'd forgotten. Lately I often had to explain things more than once.

"You can't buy passage unless you have enough extra for insurance, and travelers' checks, and passport tax. The company has to protect itself. Unless you're financially responsible,