The story is made up of several novellas strung on a rod plot – the journey of a young vacuum welder Yura Borodin on Takhmasib from the Earth to Saturn in the company of the ship’s crew and inspector Yurkovsky.
The famous captain of the spacecraft “Takhmasib” Bykov and the planetologist Yurkovsky leave for a flight to inspect space objects. Sister Yurkovsky as always watching them from the bar: the brother flies with Bykov, so she is calm.
At an international transshipment point, a young vacuum welder Yura Borodin is looking for an opportunity to get on Saturn’s satellite. He fell behind his group. In the cafe he meets a man who leads an ideological discussion with the barman, condemning the values of capitalism and defending the rightness of communism. The person advises Yura in the evening to go to room 306 in the hotel. Perhaps he will be helped to reach the satellite.
In the room Yura sees Bykov and Yurkovsky. After listening to Yura, the severe Bykov writes him on the ship as an intern. Flight engineer Zhilin, who turned out to be a man from the cafe, will explain to the young man his duties.
Mars. In the observatory, young astronomers are discussing the situation: huge flying leeches began to attack people even during the day, it is very difficult to shoot them.
The next day a meeting is being held: discussing a plan to round out leeches. It is assumed that their shelter is near the Old Base.
People gather on the ruins of the Base. One tracker shows in the cement crack a stalk of a thorn with a flower. It rarely blooms, every 5 Martian years. After each flowering there is a ringlet. Rim eight, which means that the plant has 85 terrestrial years. “This building was not built by people, it’s not cement… And leeches knowingly attack two-legged upright”. This means that the Base was not built by people: studies on Mars are conducted only thirty years.
A radiogram on the arrival of Yurkovsky, the inspector general of the International Space Communications Directorate (MUKS), arrives on Mars.
Yura likes Yurkovsky, the navigator Krutikov, who was commissioned to write memoirs. Bykov Yura considers a boring person (he does not like the most boring things!): Everyone works, but he only reads magazines and newspapers. But Zhilin explains: the captain is responsible for the organization of the flight, before the flight he does not have a free minute.
During the voyage, it is needed when a catastrophe happens.
After the raid on which many leeches were killed, a pathfinder comes to the observatory at night and informs the astronomers that all work will be stopped for two months. The ranger wears a watch on both hands: the leeches attacked only to the right, on the left the leech only once fell on the left-hander, wearing the clock on his right hand. On the pathfinder did not attack even once. Perhaps the leeches are afraid of ticking. So he tested his hypothesis.
Yurkovsky believes that they are obliged to influence Yura, teach him. At the station for the study of gravity, Yura gets acquainted with the young guys, who are completely absorbed in interesting work, despite many problems.
Also, “Tahmasib” visits the space mine, where precious stones are mined. The manager violates international legal norms: he permits to work overtime (although this is fraught with radiation paralysis), covers those who illegally have weapons. Followers of the order in the mine can not do anything about it. Yurkovsky appears at the mine and removes the manager from his post. He advises working people to choose a safer and more interesting job.
Returning to Tahmasib, Yurkovsky tries to persuade Bykov to let him go to Saturn – to explore the rings that still pose a mystery to science. Bykov considers this dangerous, and the probability of discovering something is very small. To support the planetologist, Zhilin tells an unusual story.
As a teenager, he met a strange person who called himself a giant fluctuation. With them things were constantly happening, the probability of which was negligible. He saw the auroras in Alma-Ata, the Broken vision in the Caucasus and twenty times the green ray, or “the ray of hunger.” In his presence, water was boiling in a vessel of flowers, and in the room frost fell. In his tent, ball lightning struck repeatedly. Once it became the source of a strong magnetic field: metal objects were falling on it. He even fell meteorite. And on the day of the conversation with Zhilin, the girl with whom the “fluctuation” was walking, suddenly flew away. Frightened that he would bring trouble to the interlocutor, the strange man left.
Bykov advises Zhilin to insert this story into his memoirs, since Krutikov’s laurels do not give him rest.
In the evening, Zhilin watches the navigator, who reads the “Tale of Genji” for the fifth time. Try now to sit Jura for a novel of a genius Japanese! While Yura prefers irresponsible heroic adventures to the drama of the human soul. Zhilin himself does not let go of the strange feeling that he left something important on the Earth. There are young people, children. How many things could he teach them!
In the best space observatory with Yurin help it is possible to find out that the director pushes out the guys, preventing them from doing independent scientific projects. For arbitrariness, Yurkovsky removes the director from office.
Yurkovski asks the director of the system to send Yuri to the place where Borodin’s group is currently working. The crew of Tahmasib is getting acquainted with the guys who are researching the rings of Saturn.
Zhilin tells everyone a true scientific history. On the island of Honshu found a system of caves. In one, petrified traces of primitive people were found. Between the traces of bare feet – one single trace from the boot. No doubt at the age of the trace there. The versions are coming out, where he could come from. The second track from the boot in the cave remained on the ceiling.
Yurkovsky persuades Bykov to give him the navigator Krutikov to the cosmographer. They fly to the rings of Saturn.
Bulls keeps communication with him. Despite the captain’s prohibitions, Yurkovsky and Krutikov go too close to the ring. The ring is amazingly beautiful. Yurkovsky and Krutikov come closer and hear the phrase: “Here they are, the aliens.” They have some kind of find. Then something happens. Bykov realizes that his friends were killed.
Now Yura realizes: no feat is worth living, it’s painful to lose people when you know them.
Bykov and Zhilin arrive on Earth. The column engineer sees a woman behind the column. Her flabby face is familiar to him. Zhilin thinks that the main thing is on the Earth, and decides to stay here.