On a Saturday morning, the backyard smelled of pancakes and wet grass. The sun peeked between the laundry that her mother had hung on the string, and sparrows squabbled over a crumb under the bench. Zosia put on her red trainers, tilted her headband with the shiny star and carefully placed her invention on the windowsill. - 'Attention, the Cosmos Listener is taking off,' she whispered with a smile. The Cosmos Listener looked like a flying pot. It had a tea strainer, a piece of umbrella, the wires from a torch and the headphones from an old record player. When Zosia pressed the green button, a blue light blinked inside. Usually only a quiet bzz could be heard... But today something beeped differently: beep, beep... biiiip! - Did you hear that? - Olek, Zosia's younger brother, wearing a bicycle helmet and with his shoe only tied in a bow, ran into the kitchen. - Can I help? - Come on! - Zosia picked up the Listener. - That sound is not from the radio. He's sort of... calling out. The cat Pixel dragged himself on the rug and slowly, with his tail like a plume, ran after them to the staircase. The door to the backyard creaked open and they were already outside, under an old walnut tree, next to the yellow digger in the sandpit. Beep, beep... biiiip! - There! - Olek pointed to the sand. On top, a few grains trembled as if frost had wandered into a box of sand. Zosia knelt down. In the middle of the sandbox lay a small, transparent blob. It was not wet. It looked like a glass button, and there were thin silver lines spinning in the middle. When the Cosmos Listener approached the drop, the beep turned into a soft melody. - Hello? - Zosia said very quietly, as if to a snail. - Can you... can you hear? The drop flashed once and then a second time. A thin thread of light appeared on its surface. It floated above the sand and began to draw shapes in the air. First a rectangle - it was a bench. Then a circle - the wheel of Olek's bicycle. Then a long rectangle with four windows - their block of flats. - She's drawing our backyard! - Olek jumped up and down. - Let's call her Spark! - OK, Sparkle - agreed Zosia. - Show us what you want. The thread of light twitched and made a pulsating dot on the drawing just below the swing. The dot flashed faster and faster, like a little heart. - It wants us to go there,' whispered Olek. Pixel snorted, as if he understood too, and took off at a brisk trot, tail sweeping the grass. Zosia carefully took Sparkle in her hand. She was as light as a feather and as warm as a stone that had been lying in the sun for a long time. As they walked past the ladder, the wind quieted for a moment. Even the leaves on the walnut tree stopped rustling, as if they were listening. - Children, don't go far! - called out from the window. - Only to the swing! - replied Zosia and squeezed Olek's hand tighter. Under the swing, the ground was soft and dark. The sparkle slipped out of Zosia's hand and, as if pulled by an invisible rubber band, rolled onto the board of the swing. Suddenly it got bigger - not like a drop, but like a soap bubble. In the transparent bubble, swirling dots arranged themselves into stars. Zosia and Olek made big eyes. Pixel - round. - Wow - whispered Olek. - She's got... night inside! Zosia pressed the Cosmos Listener closer. Numbers beeped in the headphones: pi... pi... pi... As if someone was counting very quietly and slowly. Three dashes appeared on the surface of the bubble, then two, then one. - She is counting down something - said Zosia. - But what? The boards of the swing squeaked, although no one was sitting on them. The bubble pulsed in an even rhythm: light, dark, light. The sparrows fell silent. On the balcony, someone stopped fluttering the carpet. The air became thick and cool, like just before a storm, only without the wind. - Can you hear? - Olek swallowed his saliva. - The ground... is trembling? The ground beneath their knees really trembled, so softly that the sand in the sandpit rustled like sugar in a sugar shaker. The pixie teased its tail and stood like a statue, looking straight up at the sky. Zosia tightened her fingers on Olek's hand. The Cosmos Listener blinked all the lights at once. A new shape appeared in the middle of the bubble: a long shadow, what looked like a wing, but was not a bird's wing. The shadow moved slowly across their hands and across the grass, as if someone had run over a huge, soft scarf. - Zosia... - Olek pressed closer to her. - What's that... Zosia raised her head. The sky above the courtyard, usually as blue as a crayon from a pencil case, now seemed to be pulling apart - the way a curtain pulls apart in a theatre. Lines of light shone between the clouds, silent as a whisper. Something large, bright and completely silent began to descend straight over the swing.