The wavelength of a single x-ray is smaller than a single atom.
This is what is left of a star whose life ended in a huge explosion long ago. It is called the supernova remnant Cassiopeia (cas-ee-oh-PE-a) A. All of the elements that make up the sun and planets in our solar system, and all the elements on Earth and in our bodies are "cooked" in these exploded stars. The bright point near the center is the neutron star that remains.
This image was made with the Chandra X-ray Observatory, placed in orbit around Earth by the Space Shuttle in July 1999. Chandra studies high-energy regions of the universe, such as hot gas in the remnants of exploded stars and clusters of galaxies, and matter falling into black holes or shooting out of active galaxies in jets.