Nebulae are merely gaseous clouds of different elements, and in some cases even organic molecules, which are suspended in the vacuum of space. Their alluring forms churn and swirl slowly about, victims to gravitational fluctuations, which in some cases create beautiful formations for our telescopes to observe.
Below you can see the difference in a nebula pictured by the visible light portion of the EM spectrum versus the infrared portion…
Visible light
images courtesy of NASA, ESA/Hubble and the Hubble Heritage Team / spacetelescope.org / spacetelescope.org
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