The main character is a young man named Alex, who is part of the team of explorers. He is fascinated by the technology of the pulsar, which is a device that allows them to travel through space and time. The plot of the book is divided into three parts: the first part describes the preparation of the expedition, the second part describes the journey through space and time, and the third part describes the consequences of their actions. In the first part, we learn about the team of explorers, their training, and the technology they use to travel through space and time. We also see how they prepare for their mission, including packing supplies and equipment, and saying goodbye to their loved ones. In the second part, the team travels through space and time using the pulsar, visiting different planets and encountering various challenges along the way. They meet alien civilizations, some of whom are hostile towards them, while others are friendly and offer help. They also encounter strange creatures and landscapes that challenge their understanding of the universe. In the third part, the team returns to Earth and must face the consequences of their actions. They realize that their journey has changed them and that they have gained a new perspective on the universe and humanity's place in it. They also understand that their actions have had a profound impact on the future of humanity and that they must now work to ensure that this future is a positive one.

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