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"What does Hubble’s infrared vision help 
astronomers see?"

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Infrared is an important wavelength for astronomers because of several reasons.

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The expansion of the universe to see farther back,

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looking through dust clouds and 
looking at cooler objects like planets.

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"Saturn - Visible"

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"Saturn - Infrared"

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"Jupiter - Visible"

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"Jupiter - Infrared"

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We can see into dust clouds the way that 
infrared does it the longer wavelengths  

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of light actually can go bending 
around the obstacles like dust grains.

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So we see around the dust grains 
and able to see inside those  

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opaque clouds to see what's happening like 
in the Orion Nebula and the Eagle Nebula.

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Infrared is important, also when we 
want to see the most distant galaxies  

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they appear to be running away from us at immense 
speeds because of the expansion of the universe.

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The light that we receive from those 
distant galaxies had been stretched

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along with the expansion of the universe so that 
it is much longer wavelengths, which means it started  

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off with visible light and it's now infrared.
So if you want to see those first galaxies  

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you need an infrared telescope to pick up the 
light that started out as visible wavelengths.

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