The thing sat on a foam cradle inside a glass box, and it looked like a piece of sky somebody had cut out with scissors.
"Don't breathe on it," Soren's aunt said from the doorway, not really looking. She was wrestling a cart full of meteorite labels. "That's the last piece. Aerogel. Real space stuff, flew on a comet mission. I'll be back in ten. Pack the foam around it, don't pick it up."
Then she was gone, and it was just the two of them and the blue.
"It's not blue," Maya said.
"It looks blue."
"Look behind it." She moved her head. "Against the dark wall it's blue. Against the lamp it's kind of orange." She moved again. "It's not colored. It's doing something to the light."
Soren leaned in until his nose nearly touched the glass. "Same way the sky does it. Little stuff scattering the blue out."
"How little?"
"Smaller than I can think about, probably."
Maya put one finger on the lid of the glass box. "She said don't pick it up. She didn't say don't open the box."
"Maya."
"I just want to know how heavy a piece of sky is."
The lid lifted off easily. The blue piece sat there, the size of a deck of cards, holding perfectly still. Maya slid one hand under the foam cradle and lifted the whole thing, foam and all.
"Okay," she said. "Now I take the foam away."
She tipped the cradle gently and the blue piece slid onto her open palm.
She went very quiet. Then she held her hand out flat toward Soren.
"Hold your hand under mine," she said. "In case."
He did. She turned her palm over. The blue piece came to rest in his hand, and he gasped, an actual gasp, the kind he was embarrassed about a second later.
"It's not there," he said.
"It's there. You're looking at it."
"I'm looking at it but my hand thinks it's empty." He bounced it, the tiniest bounce. "It weighs less than the air I just breathed out. That's a real thing I'm holding and my hand can't find it."
Maya was already somewhere else in her head. "It's almost nothing," she said. "So it's almost all holes. That's the only way. If it's that big and weighs that little it's mostly empty inside."
Soren got out his notebook with his free hand, set it on his knee, and wrote held it, no weight, blue. His pencil pressed harder than usual.
"How empty, though," he said. "Like a sponge?"
"Smaller holes than a sponge."
"How do you know?"
"Because I can't see them." Maya tapped the surface, barely. It was firm, dry, strange, like the skin on cold pudding made of glass. "A sponge you can see the holes. This is smooth. So the holes are too small to see. Smaller than light."
Soren stopped writing. "That's why it's blue."
"What?"
"That's it, that's the same thing as the sky. The holes are so small they grab the blue light coming through and throw it sideways, like air does. The color isn't paint. The color is the size of the holes." He looked at the piece in his hand with something close to alarm. "I'm holding a thing that's the color of how empty it is."
Maya laughed, delighted. "Say that again."
"No."
There was a laminated card taped to the inside of the box lid. Maya read it out loud, fast. "Silica aerogel. Up to ninety-nine point eight percent air." She looked up. "Ninety-nine point eight. So the part that's actually stuff is the other point two."
"That tiny bit is doing all the holding."
"Read the rest."
Maya kept going, then she stopped, then she read the same line again silently, her lips moving.
"What," Soren said. "What does it say."
"It says one gram of it," Maya said slowly, "if you unrolled all the inside walls of all the holes and laid them flat, would cover a basketball court."
Neither of them said anything.
Soren looked down at the blue piece in his palm. It was smaller than a deck of cards. "There's no way," he said. "There's no room."
"There's tons of room," Maya said. "That's the whole point. It's all room. It's folded."
"Folded."
"The walls are folded up so small that a basketball court of wall fits in your hand." She put her own finger near it again and did not touch. "You're holding a basketball court, Soren. Folded down past where your eyes work. The flat part you can see is the only part that's lying. Underneath it goes down and down and down into more surface than the room we're standing in."
Soren held very still so his hand wouldn't shake.
"All of it dry," he said. "All of it just sitting in your palm weighing nothing, and you'd never know."
"You'd never know," Maya said. "Unless you picked it up."
They heard the cart rattling back down the hall.
Maya didn't rush. She slid the foam cradle back under Soren's hand, tipped the blue piece into it the way you'd pour something liquid, and set the cradle in the box. Soren put the lid down so gently it made no sound at all.
When his aunt came in they were both standing exactly where she'd left them, looking like nothing had happened.
"Packed up?" she asked.
"Packed up," Soren said.
She wheeled the box out. Through the glass, against the dark hallway, the piece went blue again, then orange under the exit light, then blue, blink blink, all the way to the door.
Soren held up his empty hand and turned it over in the lamplight, looking at the palm, then the back, then the palm.
"It still feels empty," he said. "It's never going to stop feeling empty."
Maya watched the blue go out the door. "Spread it out," she said quietly, "and it would cover the whole floor in here."
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A science-verified short story for curious kids · Curiosity Land