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Hey, Stargazers! Nebulae are 
often known for their 
breathtaking beauty.

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They're star-forming 
clouds of gas and dust

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and here are the five major 
categories of nebulae and some 
examples of each one.

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First, we have emission nebulae. 
They get their name because they 
emit their own light. The 
ionized

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gas in this kind of nebula is 
high energy, which is what 
causes them to glow. A famous 
example of

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an emission nebula is the Orion 
Nebula, a huge star-forming 
nebula in the constellation 
Orion.

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This is the closest nebula to 
Earth, so you can see it even 
with the naked eye.

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Next are reflection nebula. 
These nebulae reflect the light 
from nearby stars.

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The stars aren't powerful enough 
to energize the gas like 
emission nebulae, but they are 
powerful enough

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that their light scatters 
throughout the gas often giving 
it this bluish glow. Kind of 
like

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a street lamp, illuminating the 
fog. An example of a reflection 
nebula is one called NGC 1999,

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which is illuminated by a bright 
recently formed star close to 
the famous Orion Nebula.

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The third category of nebulae is 
what's called planetary nebulae. 
They get their name from their

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fuzzy cloudy shapes that 
resemble planets. However, these 
nebulae actually have nothing

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to do with planets. They just 
form during the death of 
low-mass stars, no big deal. 
When stars like

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that die, they expel shells of 
gas into unique shapes. The 
Helix Nebula is a great example 
of

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a planetary nebula. It kind of 
looks like a bubble or an eye 
from Earth's point of view. 
Pretty cool.

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So next category is what is 
called supernova remnants. It's 
a great band name. Supernovas

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happen when stars explode and 
shoot their contents into space. 
The debris left over

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from the explosion forms an 
expanding nebula. One of the 
most famous examples

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is the Crab Nebula, which was 
created by a star explosion in 
the year 1054. At the

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time, astronomers recorded it 
being so bright that they could 
even see it in the daytime sky.

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And finally we have dark 
nebulae, otherwise known as 
absorption nebulae. These clouds 
contain such a

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large amount of gas and dust 
that they don't emit or reflect 
light and instead they block

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light coming from behind them 
and what you see are oddly 
shaped dark clouds against 
brighter

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stars. An example of this is the 
iconic Horsehead Nebula, which 
is a favorite target for both 
amateur

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and professional astronomers and 
there you have it - the five 
main categories of nebulae.

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These giant clouds of gas and 
dust truly give us some of the 
universe's most beautiful images

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in space and while we have 
fantastic telescopes that give 
us these images, many nebulae 
are able

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to be seen from Earth during a 
stargazing session. So remember 
friends, keep looking up!