He reached there in time to see the huge door slide open, then Cynthia stepped through, and the door closed. Carston waited, giving her time to leave the tunnel, before he followed. Finally he entered the tunnel himself, having long since learned how to operate the mechanism of these doors. Cynthia was gone; the outer doors were closed. Carston hurried down the long tunnel. The magnetic degravitizing coils along each side were silent now, would remain so until the Spacer's return. Carston reached the racks of vacuum suits near the outer door, quickly donned one and was soon outside the Base. Against the sun-swept horizon, a hundred yards away, he could easily discern Cynthia's metal-encased figure. She kept close to the shadows at the foot of the low lying cliffs. Not once did she look back. A quarter of a mile further, she turned sharply, entered a narrow, steep-walled canyon. Puzzled, Carston hurried forward. He reached the canyon and entered it, realizing that this must be one of the few places on Vulcan's surface where there was anything simulating night; it wasn't really dark, but sort of a twilight gloom between the rock cliffs sheering upward. And he saw Cynthia. She hadn't gone far. Her vacuum-suited figure stood very still, and she seemed to be staring up at the immensity of space. Carston crept closer, came very near indeed, until he could see the profiled whiteness of her face beneath the helmet. Carston stared too, following her gaze. At first he didn't see a thing. Then, high on the horizon, out of the sun's glare, right between the canyon walls ... he caught the bright blue glint of a star. He suddenly realized what it was, and with a sharp intake of breath he whispered: "Earth!" * * * * * She must have had her helmet phones on. She turned slowly to face him, and Carston was startled at the clear-cut radiance of her face. "It's the Earth, yes ... it's beautiful. There's no other place on this planet where you can see it like that, and then only when the position is right. Sometimes not for months...." Carston stepped quickly to her side. Cynthia averted her face, but not before he saw the glint of tears in her eyes, and the lengthening glimmer of one that rolled down her cheek beneath the transparent helmet. For an instant, Carston was dumbfounded. Then a vast exultation surged within him. "I knew it!" he whispered fiercely. "Almost from the first moment I saw you, I sensed there was something artificial beneath your mask of hardness. This is it! You don't hate Earth at all, Cynthia, you've never hated it!"