Discovery of X-rays

Syllabus: GS 3/Science and Technology 

In News 

• 129 years ago on 8 November, X-rays were discovered. 

Discovery of X-rays

• Wilhelm Conrad Röntgen discovered X-rays in 1895, noticing that they could produce images of bones by passing through flesh and other soft tissues.
  • Named “X-rays” to denote their unknown nature.
  • Immediate public interest and intense research began in early 1896.
• Properties of X-rays: X-rays have much higher energy and much shorter wavelengths than ultraviolet light, ranging from 0.03 to 3 nanometers, about the size of an atom.
  • Scientists usually refer to X-rays by their energy levels rather than wavelengths.
  • High temperatures (millions of degrees Celsius) emit X-rays, as seen in objects like pulsars, supernova remnants, and black hole accretion disks.
• Further Scientific Discoveries: J.J. Thomson discovered X-rays ionized gases, leading to the discovery of electrons in 1897.
  • H. Becquerel’s research led to the discovery of radioactivity in March 1896.

Applications

• Medical Applications: Physicians started using X-rays in January 1896 to examine bones and organs.
  •  X-rays create images by shooting rays through the body, where bones absorb more rays and cast shadows on X-ray film, making the bones visible.
• X-rays in Astronomy: The Sun’s corona, which is hotter than its surface, emits mostly X-rays.
  • Satellites like Japan’s Hinode collect X-ray data from the Sun to study its corona.
  • X-ray telescopes in space (due to Earth’s atmosphere blocking X-rays) use grazing incidence mirrors to focus high-energy X-rays onto detectors.
  • X-ray data from space telescopes provide information about the temperature, composition, and density of celestial objects.
• X-rays in Planetary Exploration: NASA’s Mars rover, Spirit, used X-rays to detect zinc and nickel in Martian rocks using the Alpha Proton X-Ray Spectrometer (APXS).
• X-rays in Earth’s Aurora: Solar storms send energetic particles to Earth, creating geomagnetic storms that result in auroras and X-ray emissions.
  • These X-rays from auroras are absorbed by Earth’s atmosphere, making them harmless to people on the ground.

Source: IE