Distant objects, like galaxies, are simply too far away for our eyes to see. Many forms of energy, like radio waves, are invisible and silent to us.

With technologies like telescopes and photography, we can see the universe that is hidden from our physical senses. We can see how stars are born, or reveal the rainbow of colours hidden in white light. Technology lets us extend our perception of reality to see our place within the solar system, galaxy and an infinite universe.

Everything with a temperature above absolute zero (-273° Celsius) emits electromagnetic radiation-including you! Generally, the hotter the object, the shorter the wavelengths it emits. Cool interstellar gas emits long infrared rays. The hottest stars emit short ultraviolet and X-rays. Astonomers use different types of telescopes, depending on what wavelength they want to see.
Canadian Heritage Information Network
Australian Museums & Galleries Online, Australia; Centre of the Universe; Gemini Observatory, Hawaii; Glenbow Museum; The Manitoba Museum; National Research Council Canada; Planétarium de Montréal

© Canadian Heritage Information Network, 2003

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