Learn About Light

Light is all around us and takes many forms. The human eye can detect just a small fraction of light. The Universe gives off all types of light, and we must use sophisticated telescopes and observatories to see what would otherwise be invisible to us.

With its unparalleled X-ray vision, the Chandra X-ray Observatory is one of the important tools that scientists use to learn about the cosmos through light. Chandra provides invaluable insight into everything from exploded stars to black holes to galaxies and the clusters they inhabit. In fact, using X-ray light from Chandra, scientists are even learning about mysteries — dark matter and dark energy — that emit no light at all.

The video with closed-captions (at YouTube)

The Milky Way
NASA's Chandra Opens Treasure Trove of Cosmic Delights
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  • STOP for Science: What is Light?
    Light is a form of energy. It has properties like a wave. The energy of a light wave depends on its wavelength.
  • Field Guide X-rays & Light:
    Eventually, X-rays were found to be another form of light. Light is the by-product of the constant jiggling, vibrating, hurly-burly of all matter.
  • X-ray Images 101:
    Light takes on many forms - from radio to infrared to X-rays and more.
  • Telescopes & Light:
    Astronomers have built telescopes and detectors that can see far beyond the type of radiation we can detect with the human eye.
  • HTE: Bending of Light.
    When the path of a light ray is bent, the image of the light source becomes distorted.
  • HTE: Light That Does Not Pass
    Any time an object blocks the light from another source, it forms a shadow.
  • HTE: Atomic Collisions
    In a collision of an atom with another atom, or with a free-roaming electron, energy can be transferred to the atom.
  • HTE: Electric Discharge
    Violent electric discharges are responsible for some of the most spectacular displays of sudden energy release on Earth and in space.
  • Infographic: Atomic Collisions
    In a collision of an atom with another atom energy can be transferred.
  • Infographic: Light in the Universe
    Light is energy that can take on many forms. Radio waves, microwaves, infrared, visible, ultraviolet, X-ray and gamma radiation are all different forms of light.