The Sun Across the Electromagnetic Spectrum

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The Sun Across the Electromagnetic Spectrum
The Electromagnetic Spectrum and the Universe

• X-Ray

Ultraviolet
Visible
Infrared
Radio
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Big Idea ..
The Electromagnetic Spectrum and the Universe

• Different wavelengths of the electromagnetic
  spectrum such as light and radio waves are used
  to gain information about distances and
  properties of components in the universe

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Radio Waves and the Universe

• Many astronomical objects emit radio waves
• Astronomers can make pictures from the radio
  waves being emitted
• Radio telescopes use a large metal dish to help
  detect radio waves
• By studying the radio waves, astronomers can
  learn about the composition, structure, and
  motion of objects
• Radio astronomy has the advantage that sunlight,
  clouds, and rain do not affect observations

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What do Radio Waves show us?

• The above image shows the Carbon Monoxide (CO)
  gases in our Milky Way galaxy

Radio Waves
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Microwaves and the Universe

• Because microwaves can penetrate haze, light rain
  and snow, clouds and smoke, these waves are good
  for viewing the Earth from space
• Microwaves

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Infrared Rays and the Universe

• Satellites, like the Infrared Astronomy Satellite
  (IRAS) look up into space and measure the
  infrared light coming from things like large
  clouds of dust and gas, stars, and galaxies
• Infrared Universe

Exploring the Infrared Universe
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Sunflower Galaxy Glows with Infrared Light
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Ultraviolet and the Universe

• We can study stars and galaxies by studying the
  UV light they give off
• Many scientists are interested in studying the
  invisible universe of ultraviolet light, since
  the hottest and the most active objects in the
  cosmos give off large amounts of ultraviolet
  energy

Andromeda Galaxy in Ultraviolet
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X-Rays and Gamma Rays and the Universe

• Many things in space emit X-rays, among them are
  black holes, neutron stars, binary star systems,
  supernova remnants, stars, the Sun, and even some
  comets!
• This radiation has such high energy that
  specially made, angled mirrors must be used to
  help collect this type of light

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X-Rays and Gamma Rays and the Universe

• X-ray and gamma-ray astronomy has led to the
  discovery of black holes in space, and has added
  much to our understanding of supernovae, white
  dwarfs and pulsars
• High-energy observations also allow us to study
  the hottest regions of the Sun's atmosphere
• The Beautiful Universe
• Exploring the Universe through Gamma Rays

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Gamma Rays and the Universe

• Fermi Gamma Ray Telescope

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Spectral Analysis

• We cant always get a sample of a piece of the
  Universe
• - So we depend on light !

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Spectrographs

• Astronomers use spectrographs to gather
  information about stars, including their chemical
  compositions and temperatures

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Chemical Composition

• Chemical elements in a stars atmosphere absorb
  light from the star
• Each element absorbs light at different
  wavelengths, and each absorbed wavelength appears
  as a dark line on a spectrum
• By comparing a stars spectrum with the known
  spectrums of different elements, we can determine
  which elements are found in stars

Hydrogen
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Temperatures

• The amount of energy each of these elements
  absorbs depends on the temperature of the star
• Stars at different temperatures produce different
  line spectrums
• Astronomers can use line spectrums to find the
  temperature of stars