Why are X-ray telescopes placed in space?

X-ray telescopes are placed in space because the Earth's atmosphere absorbs X-rays, making it impossible to observe X-rays from the ground. X-rays are a form of electromagnetic radiation with a wavelength shorter than ultraviolet light and longer than gamma rays. They are produced by high-energy processes in the universe, such as the accretion of matter onto black holes and the explosions of supernovae.

X-ray telescopes are used to study a wide variety of objects in the universe, including stars, galaxies, and clusters of galaxies. They are also used to study the hot gas that fills the space between galaxies. By observing X-rays, astronomers can learn about the physical processes that are occurring in these objects.

To avoid the absorption of X-rays by the Earth's atmosphere, X-ray telescopes are placed in space. This allows them to collect X-rays from distant objects without any interference. X-ray telescopes are typically placed in low Earth orbit, where they can be easily serviced and repaired.

Some X-ray telescopes are also placed in higher orbits, such as geosynchronous orbit. This allows them to have a wider field of view and to observe objects for longer periods of time. However, X-ray telescopes in higher orbits are more difficult to service and repair.

The placement of X-ray telescopes in space has revolutionized the study of the universe. It has allowed astronomers to observe objects that were previously invisible and to learn about the physical processes that are occurring in the universe.