Maks looked through the giant glass of the Ganymede Orbital Station at the Earth, which seemed like a blue and white ball suspended in the blackness of space. Lena, his best friend and the most talented young mechanic on the station, was just finishing fitting a new repair laser to their robot. - Do you think we'll discover anything interesting today? - She asked, looking at Max from under her dishevelled fringe. - All disappearing satellite signals are interesting! - replied Maks, putting on his spacesuit with the School of Young Technicians emblem. - Also... Suddenly, Captain Sophie's voice rang out through the loudspeaker: - Maks, Lena! Quickly to the airlock! We're losing contact with another satellite! The children exchanged glances full of tension. There had been strange occurrences for a week - satellites that were helping people on Earth had stopped sending a signal exactly when they were orbiting over a distant sector of the orbit. Nobody knew why. After a few minutes, Lena and Maks were already sitting in the repair pod, and the Mayster robot was ready to go. The metal arms of the Mayster flashed in the artificial light. The airlock door closed and the capsule slowly floated outwards. The space around seemed infinite and silent. - Course set for ECHO-7 satellite - the on-board computer beeped. - Estimated time of arrival: 3 minutes. Maks checked the instruments. Through the glass, Lena watched space debris drifting in the distance and the vanishing points of light of other satellites. - 'Look,' she said suddenly, pointing with her finger. - 'There, up ahead, is some kind of strange fog. In fact, a grey, shimmering cloud began to appear in front of them, as if someone had spilled milk in the vacuum. Suddenly a warning message appeared on the screen: - Attention, non-standard signal interference detected. The capsule shook, and the Mayster robot emitted a quiet screech. On the monitor, the ECHO-7 satellite was just disappearing inside this mysterious fog, and a strange electronic noise could be heard in the speakers, as if someone was trying to talk to them.... - 'Maks, can you hear that? - whispered Lena, grabbing his hand. Before the boy had time to answer, the capsule was surrounded by shimmering lights and their instruments began to go crazy. Everything around them spun faster and faster, and an incomprehensible flashing sign appeared on the screen....