"Is it like vacuum?" he wonders. "Or is it smelly air?"

"It's not vacuum, and I don't know how it smells. It doesn't have enough oxygen in it."

"Well, it started out that way, and people are working on making it have good real air instead, but it's taking a long time."

"Why's it take so long?" he asks. "Can't they just get it from somewhere that has lots?"

"Most of the places that have air want to keep it all for themselves. Even if they didn't, you'd need so many ships to hold all the air that you'd need to cover up a whole planet. Ships are pretty small compared to planets."

"I guess so," he concedes.

"So they're figuring out how to make it at home, out of the fake air, with algae and stuff like that."

"What's an algae?" he asks next.

"It's a little plant that lives in large groups. Some of it looks like green, wet hair."

"That sounds weird," says Nikki.

"It's kind of weird. But it's good at making oxygen for the air."

"So people can breathe it?" he asks, in the interests of clarification.

"Yup. Algae is helpful like that. All plants are, but algae grows quick and it's less picky about some things than some other plants are."

"For one thing, Komarr doesn't get very much sunshine, and plants love sunshine," supplies Linya.

"Oh. Why doesn't Komarr get sunshine?" asks Nikki.

"Its sun is far away. It has a mirror to help it get more sun, but that only helps a little."

"A mirror?" he asks.

"Yep! A big space mirror to reflect the sun at the planet."

"Wow. It must be so big!" he says, impressed.

"It's huge! There's actually seven mirrors, all stuck together."

"Wow," he repeats.

"On Earth, they have a huge moon, even bigger than the mirror Komarr has. And no one had to build it, it's just there, and it reflects light too. It looks like a pearl in the sky at night when it's full."

"Wow! I wanna see a picture," he says.