The curiosipede was perfectly capable of traveling in the dark, in principle. In practice Nyssa found it harder to come up with things to wonder about when she had to squint at everything in the starlight to figure out what was there to question. Besides, she was very, very tired. Finally she spotted, glittering faintly so she could see it with her darkness-adjusted eyes, a huge glass dome with a few apertures just big enough for a girl and a half-hour to creep through at its base where it met the ground. The curiosipede ran out its momentum getting them there and drifted to a stop right by one of those little holes, and Nyssa, glad to at least have something above her in case it should rain, crawled inside.

It was quite comfortable under the dome, with the ground soft and dry and mossy under her hands and knees while she looked for the best place to lie down. Her bag served surprisingly well as a pillow. And it was warm enough that she didn't require any blankets besides Pomodoro (who could spread out like a throw blanket over Nyssa's body, but even at its greatest extent only measured five minutes by six and would not have been able to keep an entire human warm if it had been a chilly night). Nyssa lay on her back and looked up through the glass.

The stars had been incredible enough while they'd been rolling down the road, but the dome seemed like it might have been intended for astronomical observations - the stars seemed magnified. Not to the point where any were omitted from the field, but instead of seeing the trees and bushes and scenery that Nyssa remembered there being about the dome, the stars were blown up to cover the whole sky. If Nyssa held her head just so, she could arrange to see absolutely nothing but night sky and the stars.

She had never seen so very many stars in her life. There was a whole sea of them up there. A torrent of stars. She felt almost like she was falling into them, that stars would soon be whizzing past her ears and sticking like burrs in her hair.

Nyssa watched them wheel slowly across the sky for what might have been a minute or an hour, but if it was an hour, Pomodoro didn't so much as twitch at the use of time. And then at last Nyssa fell asleep.

When she woke up the sun was turning the sky pink and gold, and the stars were gone. The dome still magnified the sky just above to the exclusion of all the other things outside.

"I guess we should probably go," she said to Pomodoro.

"It's okay to watch the sun rise," Pomodoro told her, "if you like watching the sun rise."

"I think I do like it," Nyssa said, and they lay there under the dome, watching the colors, until a spider the size of a house extended a leg up the side of the dome and then crawled the rest of the way onto the glass with the other seven, fangs wiggling horribly, eight eyes staring unblinkingly.

"eep," said Nyssa. The spider didn't seem to have noticed them yet. Maybe if they held really, really still, it wouldn't see them, and it wouldn't bite through the glass dome and come and eat them.

The spider seemed to be taking its time about crossing the glass. Nyssa waited, trying not to tremble too much, while it made its leisurely way up to the summit of the dome. "It's so big," she whispered to Pomodoro.

Pomodoro scrunched from a blanket into a blob again. "What is?"

"Don't move! There's a huge spider and I don't want it to see us."

"Oh!" said Pomodoro. "Goodness, that really is huge, isn't it. Are you going to run for it?"

"Look how long its legs are! It could outrun us no matter how much I wind up the curiosipede before we get out of the dome," Nyssa said.

"Maybe it won't chase us?" Pomodoro suggested.

"I don't want to risk it," Nyssa said. And she lay still on the ground, watching the spider when she could bear to look at it at all. Gradually she became hungry and wanted to rummage in her bag for some of the provisions she'd picked up in Ference, but she still didn't dare move - she was sure that the glass would shatter if the spider did anything more than step slowly across it. It was so incomprehensibly huge, she wasn't sure how the glass didn't groan under its weight. Perhaps glass didn't groan. What did it eat? Most spiders caught flies in their webs, she was pretty sure, but this one must eat something bigger, probably little girls just like her for breakfast every day...

A small rosy-cheeked woman in a labcoat bustled into the dome, looking thoroughly unconcerned with the spider. She just ducked through the aperture, completely ignoring the bug overhead as though it weren't there - no, not quite. She did look at it with minor annoyance and sigh, but before she could double-take and have some more sensible reaction like screaming, she noticed Nyssa and Pomodoro.

"Oh! Hello. I'm the Astronomer, who are you?" she asked them.

"I'm Nyssa, and this is Pomodoro," Nyssa said quietly, "but more importantly there is a spider up there and I don't think you had better move, so if it hasn't noticed you yet it won't."

The Astronomer blinked at them. "I'm not particularly afraid of spiders," she remarked. "Certainly they're a nuisance, I will give you that, but I don't think that's any call to go paralyzing myself over it."

"This one is very, very big," Nyssa said, "I think likely the biggest spider in the entire world."

"I doubt it," the woman said, looking up assessingly. "It's certainly blocking the view, though. Are you very frightened of things with eight legs? I can go out and brush it away for you." And out she went.

"No - wait!" cried Nyssa, sure that this well-meaning but deeply confused person was about to be devoured alive by the giant creature. But instead, after a delay, a feather duster - so huge that it was barely recognizable as such - whiffed across the glass dome, and took the spider with it when they collided, and then the glass was clear, showing only the excellent view of the magnified sky.

Back inside came the little Astronomer. "There you are," she said. "I hope that helps."

"How did you do that?" asked Nyssa. "You aren't big enough to hold a duster that size! Or to move a spider that large with one even if you could! It was bigger than an elephant! It could have eaten you!"

"My dear," said the Astronomer, "the spider was only about this big." And she held her thumb and forefinger about an inch apart. "The planetarium magnifies what's overhead. Every now and then an animal, like that spider, climbs onto it, and it can look enormous from the inside. But if you look at things from outside you'll see that often they're not much."

"Often?" said Nyssa tremulously.

"Well," allowed the Astronomer, "sometimes a thing looks bad from outside, too. And sometimes even a spider that is really small can be a problem for someone who is particularly sensitive to spiders regardless of size. And sometimes, if you aren't under a planetarium, something might seem small but really be huge, instead of the other way around. But when you've seen enough things through the dome you can often guess which will be which from experience. Don't you worry, everyone makes mistakes like this sometimes. Next time you see something on the planetarium dome, you'll know that things like that aren't always as much of a problem as they seem."

Nyssa took a deep breath and finally sat up, hugging Pomodoro to her chest. "Okay," she said. "Thank you. - what is this place?"

"It's for observing the sky, of course," came the reply. "Mostly at night, but today I'm looking at clouds." She pulled out a notebook and started writing down things about the clouds. "You're welcome to stay if you like, there's plenty of room. But please don't distract me too much, I'd like to finish my observations before the planetarium wanders off. They do that, you know, it's in the name."

"They do? Gosh. I'm glad it stayed in one place overnight. Perhaps it was asleep. I'm actually just going to have some breakfast and then go on my way," Nyssa said. "I'm on my way to... I don't know what it's called, actually. The place where the Princess's father lives."

"Percepolis!" said the woman. "Why, I live there. It's not too far to walk. I'm sure you'll have a marvelous visit."

"Thank you," said Nyssa. And she ate some packed disjunction sandwiches and some conjunction links, and then she boarded the curiosipede and went on to Percepolis. Behind her, she could hear a heaving noise as the planetarium pulled up spindly legs it had planted in the earth, heaved itself to its pointed feet, and, ignoring the shouts of the Astronomer, wandered away.