X-ray telescopes need to be in space because Earth’s atmosphere absorbs most X-rays, preventing them from reaching ground-based instruments. The atmosphere acts as a shield, blocking high-energy radiation like X-rays and gamma rays. Without this absorption, X-rays can’t pass through to the Earth’s surface, which is why we need to place telescopes in space to observe objects emitting X-rays, such as black holes, neutron stars, and supernova remnants. By positioning the telescope above the atmosphere, it can detect X-rays directly from cosmic sources, giving scientists crucial insights into high-energy phenomena in the universe.