The Universe. 50 Ideas

Astronomy is one of the oldest and most profound sciences. Thanks to the knowledge accumulated by humanity since our ancestors began observing the movement of the Sun and stars, the understanding of the place of humans in the Universe has radically changed. Every breakthrough in science has had an impact on society: in the 17th century, Galileo was arrested for his controversial teaching that the Earth revolves around the Sun. Similar skepticism was also aroused by evidence that the Solar System is not located at the center of the Milky Way. In the 1920s, Edwin Hubble silenced the skeptics by discovering that the Milky Way is one of billions of galaxies scattered throughout the expanding Universe, which is 14 billion years old. In the 20th century, even more discoveries were made thanks to modern technologies. At the beginning of the century, we began to better understand the structure of stars and their engines - nuclear fusion, while also gaining knowledge about nuclear energy and radiation. Later, radio astronomy emerged, pulsars, quasars, and black holes were discovered. New windows into the Universe opened up - from relic radiation to celestial X-rays and gamma rays, and each frequency brought its own discoveries. This book is an excursion into astrophysics from the perspective of modern science. The first chapters describe the great philosophical breakthroughs in our understanding of the scales of the Universe, while also explaining the basics - from the laws of gravity to the structure of the telescope. The next section is about what we know about cosmology, the study of the Universe as a whole, its components, history, and evolution. The theoretical aspects of the Universe are then described, including the theory of relativity, black holes, and multiverses. The last part provides details on what we know about galaxies, stars, and the Solar System, from quasars and galaxy evolution to exoplanets and astrobiology. Discoveries are being made more and more frequently: perhaps in the coming decades, we will...