The orbital station Aurora had already been orbiting the distant purple planet for six years. Its silvery dome reflected the light of three suns, and its crew of four counted down the days until the completion of their mission. That morning, Captain Mikael Jensen could not sleep. He lay in his capsule, listening to the regular hum of the life support systems. Finally, he decided to go to the main control module. Doctor Li Mei was already there, with a mug of coffee floating just above her head in a state of weightlessness. - 'Couldn't you sleep? - Mikael asked quietly. - 'We're getting that signal again,' replied Li. - Look. Mysterious characters flashed on the screen, completely different from any Earth languages or known codes. The signal was weak but regular, repeating every nine minutes. Engineer David entered the module, yawning and rubbing his eyes. He was immediately followed by a young researcher, Sofia. Everyone was already aware of the signal. Sofia activated the translator, even though she knew it wouldn't do any good. Instead of words, only a series of symbols appeared: spirals, triangles, something like inverted letters. - I checked the archives,' she said. - There is nothing similar in any known database. But... the signal is getting stronger. And it's as if... it's moving closer to the station. Whoever is sending it knows where we are. The voice suddenly went quiet as all the screens lit up green, then purple, and then went completely blank. For a moment, Aurora was plunged into silence. From outside, through the panoramic window, they all saw something that had not been there a moment before: a huge, glowing object, slowly rotating on its axis, from which a stream of pulsating light was coming straight out at the station. Mikael looked at the rest of the crew. The glow of something completely unknown was reflected in their eyes. They all felt a growing tension - was what was watching them going to make contact, or...?