White dwarfs are one of the most fascinating topics in the history of astronomy: celestial bodies were discovered for the first time, possessing properties that are very far from those with which we deal in terrestrial conditions. And, in all likelihood, the resolution of the riddle of white dwarfs laid the foundation for studies of the mysterious nature of matter hidden somewhere in different corners of the Universe.
There are many white dwarfs in the universe. At one time, they were considered rare, but a careful study of the photographic plates obtained at Mount Palomar Observatory (USA) showed that their number exceeds 1500. It was possible to estimate the spatial density of white dwarfs: it turns out that in a sphere with a radius of 30 light-years there Continue reading
Like all bodies in nature, stars do not remain unchanged, they are born, evolve, and finally “die.” To trace the life path of stars and understand how they age, you need to know how they arise. In the past, this seemed like a big mystery; modern astronomers can already with great confidence describe in detail the paths leading to the appearance of bright stars in our night sky.
Not so long ago, astronomers believed that it takes millions of years to form a star from interstellar gas and dust. But in recent years, striking photographs have been taken of the area of the sky that is part of the Great Orion Nebula, where a small cluster of stars has appeared over the course of several years. In the pictures of 1947. in this place a group of three star-like objects was visible. By 1954 some of them became oblong, and by Continue reading
Scientists strongly believe that black holes really exist. Albert Einstein’s general theory of relativity predicted the existence of such objects back in 1917, and over the past decades, astronomers have found plenty of evidence of their presence in many areas of outer space.
More than 5 objects are known, which probably include black holes. However, there is only indirect evidence, but there is no conclusive evidence. The most likely candidate for black holes is the X-ray source Cygnus X-1, discovered in the early 1970s in X-binary systems. The mass of the source in this system, which can be estimated from the observed speed of the optical star in its orbit and Kepler’s laws, exceeds the limiting mass for a neutron star. The Chandra X-ray Observatory found in several galaxies with a high rate Continue reading