Astronomy Today – Chapter 3
Radiation
Information from the Skies
The pancake-shaped Andromeda Galaxy lies about 2.5
million light-years away.
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Information from the Skies
• This is Helix Nebula about 650
light-years away.
• This image was not taken in
visible light.
• It shows invisible radiation;
Infrared radiation (mostly
yellow in this image) captured
by the Spitzer Space
Telescope and ultraviolet
radiation (mostly bluish) by
the Galaxy Evolution Explorer
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Electromagnetic Spectrum
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The Milky way Galaxy
(a) radio, (b) infrared, (c) visible, (d) X-ray, and
(e) gamma-ray radiationTSivayogan
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All EM Radiation
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•
•
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Light (does not mean only the visible light)
Electro magnetic rays
Electromagnetic radiation
Electromagnetic waves
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