Okay, it’s still working. The suit’s functioning okay. Settle down. Keep moving.

Turning to see how far he’d come from the underground shelter that Greg had turned into a death trap, Paul was pleased to see that its gray hump of rubble was just about on the horizon. Covered a couple of miles already, he told himself.

His boot prints looked bright, almost phosphorescent, against the dark surface of the regolith. In a couple thousand years they’ll turn dark, too; solar ultraviolet tans everything. He almost laughed. Good thing I’m already tanned.

Paul started out again, checking his direction with the global positioning system receiver built into the suit’s displays. He hadn’t had the luxury of timing his exit from the shelter to coincide with one of the GPS satellites’ passing directly overhead. The only positioning satellite signal his suit could receive was low on the horizon, its signal weak and breaking up every few minutes. But it would have to do. There were no other navigational aids, and certainly no road markers on Mare Nubium’s broad expanse.

The other shelters had directional beacons planted in the ground every mile between them. And they were no more than ten miles apart, all the way to the ringwall. Greg had planned it well; turned the newest of the temporary shelters into his killing place.

He plodded on, wishing the suit radio had enough juice to reach the tempo he was heading for, knowing that it didn’t There’s nobody there, anyway, he thought It’s just a relay shelter. But it ought to be stocked with oxygen and water. And its radio should be working.

Suddenly, with an abruptness that startled him, Paul saw the horizon flare into brilliance. The Sun.

He checked his watch and, yes, his rough calculations were pretty close to the actualities. In a few minutes the Sun would overtake him and he’d have to make the rest of the trek in daylight.