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Light Beyond the Bulb: Intro to Light
Narrator (April Hobart, CXC): The year 2015 has been declared to be the International Year of Light and Light-based Technologies by the United Nations. People around the world are using this year-long celebration, nicknamed IYL 2015, to look at all of the amazing things light can do.
Whether it comes from the Sun, a distant galaxy, or a neon sign around the corner, light is all around us. We use light to communicate, navigate, learn, explore, and much more.
Light comes in many forms. In fact, the light that we see with our eyes, the same light that makes up the colors of the rainbow,
Light is fascinating for many reasons, including the fact that it possesses qualities of both a wave and a particle. We often characterize light and its behavior based on how far apart the crests of its waves are. This is called wavelength. Alternately, light can be viewed as being composed of a stream of particles.
Another aspect of light that is so amazing is how fast it travels. Nothing in the Universe can travel faster than light. In a vacuum, light moves at an astonishing 1.08 billion kilometers per hour. In other units, this translates into 671 million miles per hour. To put this in perspective, this means light could circle around the Earth seven and a half times in just one second.
In upcoming episodes, we will look at different aspects of light. We will explore some of its intriguing properties and how humans have greatly benefited from learning all that we can about light, which goes far beyond the bulb.