“Bint!” someone said, to the adult asking questions, admonishing him.

“Look, I want to know,” Bint said.

“It’s all right,” Marce said, holding up a hand. “In fact, it did happen again, more than seven hundred years ago, when we lost contact with a system called Dalasýsla. This was before the local Flow streams were as extensively mapped as they are now. The Flow stream to Dalasýsla was apparently already collapsing when it was first colonized, it just took a couple hundred years to close entirely. Now, as it happens, the rest of the Flow streams in the Interdependency have been robust and mostly unchanged for the last several hundred years.”

This seemed to satisfy Bint, and Marce was happy this fellow hadn’t noticed he didn’t actually answer the question.

From a distance, a low crummp made it into the momentary silence of the planetarium. One of the adults in the audience started to take in a sharp breath, and then stopped.

“And I think that’s about all the time we have for today,” Marce said. “Thank you all for coming, and I hope you’ll come again another time. We’d love to see you.” A day when someone isn’t clearly shelling someone else only a few klicks away. He flicked up the house lights and waved good-bye to the children as the adults filed them out of the room. One of the adults looked back and mouthed the words thank you to him. Marce smiled and waved again.

“Still giving tours in the middle of a war,” said someone new, in the back of the planetarium. “That’s noble. Stupid, but noble.”

Marce looked up, saw who it was, and smiled again. “Well, technically, we are nobility, aren’t we, sis?”

Vrenna Claremont, in her full constable uniform, smiled back and started walking down toward her brother. “Being a noble on End is like being the richest person in a trash heap. It doesn’t mean much. Especially now, when the duke is about to get his ass handed to him and rebels are running about liberating his property. It’s not a stretch to assume other nobles will find their stuff similarly liberated.”

“My stuff is a bunch of books in graduate housing,” Marce said. “I think they’ll be disappointed.”

“You’re a professor now. You should move out of graduate housing.”

“I’m resident master. Saves on rent.”

“A count’s son, worried about rent,” Vrenna said.

“We are really unimpressive nobility, it’s true.”

There was another crummp somewhere in the distance, and it didn’t sound as distant as the last one.

“I’m doing a really good job of not panicking right now,” Marce said.

“I noticed that,” said Vrenna. “I mean, I wasn’t going to mention it. But I noticed it.”

“We can’t all have ice water in our veins.”