Astronomy
This is about the universe, black hole, stars, nebulae, milky way, celestial movement, comets, asteroids, sun and its family members.
Beyond the Rainbow
Astronomers have opened new windows on the universe by studying the kinds of "light" we can't see with our eyes. by James B. Kaler
It's everywhere around you. It pervades Earth, the sky, the universe, and is bouncing off and passing through you at this very moment. It can be highly destructive yet is utterly necessary for life. For astronomers, it's by far the most important way of unlocking the secrets of the cosmos.
We know it best as light. But the light we see with our eyes is just a tiny sliver of a vast electromagnetic spectrum produced by everything from comets to quasars. We can understand little about the universe without an understanding and appreciation of visible light and its invisible partners in the electromagnetic spectrum: radio waves, infrared light, ultraviolet light, x rays, and gamma rays. All these different forms of light are fundamentally the same thing.
Scientists now know that light can be described as a train of waves that carries energy. These waves are in fact the universe's principal means for transmitting energy. Unlike water and sound waves, however, light does not need a substance through which to travel. Instead, it consists of waves of alternating electric and magnetic fields that move through a vacuum at the cosmic speed limit of 186,000 miles (300,000 kilometers) per second. The different kinds of light are waves that have different lengths between consecutive crests or troughs.Also it is related to the NASA, ISS, voyager, moon and earth revolving satellites.
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