But Sax only said, “Algorithmic search programs are very effective,” and Maya insisted on keeping out of sight, and hardening their electronics, and sending all their excess heat deep into the heart of the polar cap. Hiroko agreed with Maya on this, and so they all complied. “It’s different for us,” Maya said to Peter, looking haunted.

There was a mohole, Sax told them one morning at school, about two hundred kilometers to the northwest. The cloud they sometimes saw in that direction was its plume — big and still on some days, on others whipping off east in thin tatters. The next time Coyote came through they asked him at dinner if he had visited it, and he told them that he had, and that the great shaft of the mohole penetrated to very near the center of Mars, and that its bottom was nothing but bubbling molten fiery lava.

“That’s not true,” Maya said dismissively. “They only go down ten or fifteen kilometers. Their floors are hard rock.”

“But hot rock,” Hiroko said. “And twenty kilometers now, I hear.”

“And so they do our work for us,” Maya complained to Hiroko. “Don’t you think we are parasites on the surface settlements? Your viriditas wouldn’t get far without their engineering.”

“It will prove to be a symbiosis,” Hiroko said calmly. She stared at Maya until Maya got up and walked away. Hiroko was the only one in Zygote who could stare Maya down.

Hiroko, Nirgal thought as he regarded his mother after this exchange, was very strange. She talked to him and to everyone else as an equal, and clearly to her everyone was an equal; but no one was special. He remembered very keenly when it had been different, when the two of them had been like two parts of a whole. But now she only took the same interest in him that she took in everyone else, her concern impersonal and distant. She would be the same no matter what happened to him, he thought. Nadia, or even Maya, cared for him more. And yet Hiroko was mother to them all. And Nirgal, like most of the rest of the regulars in Zygote, still went down to her little stand of bamboo when he was in need of something he couldn’t find from ordinary people — some solace, or advice…

But as often as not, when he did that he would find her and her little inner group “being silent,” and if he wanted to stay he would have to stop talking. Sometimes this lasted for days at a time, until he stopped dropping by. Then again he might arrive during the areophany, and be swept up in the ecstatic chanting of the names of Mars, becoming an integral part of that tight little band, right in the heart of the world, with Hiroko herself at his side, her arm around him, squeezing hard.

That was love of a sort, and he cherished it; but it was not as it had been in the old days, when they had walked the beach together.

*     *       *

One morning he went into the school and came on Jackie and Dao in the coatroom. They jumped as he entered, and by the time he had gotten his coat off and gone into the schoolroom he knew they had been kissing.

After school he circled the lake in the blue-white glow of a summer afternoon, watching the wave machine rise and pulse down, like the clamping sensations in his chest. Pain curved through him like the swells moving over the water. He couldn’t help it, even though it was ridiculous and he knew it. There was a lot of kissing going on among them these days in the bathhouse, as they splashed and tugged and pushed and tickled. The girls kissed each other and said it was “practice kissing” that didn’t count, and sometimes they turned this practice on the boys; Nirgal had been kissed by Rachel many times, and also by Emily and Tiu and Nanedi, and once the latter two had held him and kissed his ears in an attempt to embarrass him in the public bath with an erection; and once Jackie had pulled them away from him and knocked him into the deep end, and bit his shoulder as they wrestled; and these were just the most memorable of the hundreds of slippery wet warm naked contacts which were making the baths such a high point of the day.

But outside the bathhouse, as if to try to contain such volatile forces, they had become extremely formal with each other, with the boys and girls bunched in gangs that played separately more often than not. So kissing in the coatroom represented something new, and serious — and the look Nirgal had seen on Jackie and Dao’s faces was so superior, as if they knew something he didn’t — which was true. And it was that which hurt, that exclusion, that knowledge. Especially since he wasn’t that ignorant; he was sure they were lying together, making each other come. They were lovers, their look said it. His laughing beautiful Jackie was no longer his. And in fact never had been.

He slept poorly in the following nights. Jackie’s room was in the shoot beside his, and Dao’s was two in the opposite direction, and every creak of the hanging bridges sounded like footsteps; and sometimes her curved window glowed with flickering orange lamplight. Instead of remaining in his room to be tortured he began to stay up late every night in the common rooms, reading and eavesdropping on the adults.

So he was there when they started talking about Simon’s illness. Simon was Peter’s father, a quiet man who was usually away, on expeditions with Peter’s mother, Ann. Now it appeared that he had something they called resistant leukemia. Vlad and Ursula noticed Nirgal listening, and they tried to reassure him, but Nirgal could see that they weren’t telling him everything. In fact they were regarding him with a strange speculative look. Later he climbed to his high room and got in bed and turned on his lectern, and looked up “Leukemia,” and read the abstract at the start of the entry. A potentially fatal disease, now usually amenable to treatment. Potentially fatal disease — a shocking concept. He tossed uneasily that night, plagued by dreams through the gray bird-chirp dawn. Plants died, animals died, but not people. But they were animals.

The next night he stayed up with the adults again, feeling exhausted and strange. Vlad and Ursula sat down on the floor beside him. They told him that Simon would be helped by a bone marrow transplant, and that he and Nirgal shared a rare type of blood. Neither Ann nor Peter had it, nor any of Nirgal’s brothers or sisters or halves. He had gotten it through his father, but even his father didn’t have it, not exactly. Just him and Simon, in all the sanctuaries. There were only five thousand people in all of the sanctuaries together, and Simon and Nirgal’s blood type was one in a million. Would he donate some of his bone marrow, they asked.

Hiroko was there in the commons, watching him. She rarely spent evenings in the village, and he didn’t need to look at her to know what she was thinking. They were made to give, she had always said, and this would be the ultimate gift. An act of pure viriditas. “Of course,” he said, happy at the opportunity.

The hospital was next to the bathhouse and the school. It was smaller than the school, and had five beds. They laid Simon on one, and Nirgal on another.

The old man smiled at him. He didn’t look sick, only old. Just like all the rest of the ancients, in fact. He had seldom said much, and now he said only, “Thanks, Nirgal.”

Nirgal nodded. Then to his surprise Simon went on: “I appreciate you doing this. The extraction will hurt afterward for a week or two, right down in the bone. That’s quite a thing to do for someone else.”

“But not if they really need it,” Nirgal said.

“Well, it’s a gift that I’ll try to repay, of course.”

Vlad and Ursula anesthetized Nirgal’s arm with a shot. “It isn’t really necessary to do both operations now, but it’s a good idea to have you two together for it. It will help the healing if you are friends.”

So they became friends. After school Nirgal would go by the hospital, and Simon would step slowly out the door, and they would walk the path over the dunes to the beach. There they watched the waves ripple across the white surface and rise and crumple on the strand. Simon was a lot less talkative than anyone Nirgal had ever spent time with; it was like being silent with Hiroko’s group, only it never ended. At first it made him uncomfortable. But after a while he found it left time to really look at things: the gulls wheeling under the dome, the sandcrab bubbles in the sand, the circles in the sand surrounding each tuft of dune grass. Peter was back in Zygote a lot now, and many days he would come with them. Occasionally even Ann would interrupt her perpetual traveling, and visit Zygote and join them. Peter and Nirgal would race around playing tag, or hide and seek, while Ann and Simon strolled the beach arm in arm.