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the space between stars holds an array

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of vibrant clouds

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clouds that command our attention

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clouds that create spectacular displays

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clouds that seem familiar

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tenuous

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and fragile

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clouds that hold clues to star birth and

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death

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nasa's hubble space telescope has imaged

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hundreds of them in extraordinary detail

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these vast swirls of gas and dust get

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their name from the latin word nebula

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meaning cloud or mist

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nebulae is the plural of nebula and they

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come in a wide range of shapes sizes and

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forms

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emission nebulae are some of the most

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spectacular

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these opaque gleaming clouds of gas and

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dust radiate or emit their own light

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ultraviolet light from nearby stars

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energizes atoms in the cloud

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when the excited atoms lose that energy

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they release the light that gives

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emission nebulae their glow the orion

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nebula is one of the most famous

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emission nebulae

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its core called the trapezium holds four

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enormous young stars whose ultraviolet

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light powers the region's intense glow

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the carina nebula is another vast

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emission nebula and star-forming region

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in our galaxy

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within the nebula is a pillar three

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light-years tall dubbed mystic mountain

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it cloaks massive young stars some with

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jets emerging from the cloud

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hubble's infrared view cuts through the

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shroud of gas and dust revealing these

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reflection nebulae shine by the

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reflected or scattered light of nearby

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stars

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they often have a bluish color because

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the dust grains in the clouds scatter

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blue light more efficiently than red

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not all nebulae shine brightly dark or

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absorption nebulae are inky black clouds

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of gas and dust that block the light

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coming from objects behind them

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because they are dark absorption nebulae

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are hard to find

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we only see them as silhouettes against

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most large nebulae are a combination of

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emission reflection and absorption

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nebulae their dark dust lanes may give

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birth to new stars that provide the

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light needed to illuminate the cloud

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planetary nebulae are a type of emission

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nebula powered by a small to

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medium-sized dying star

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as these stars run out of fuel they

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periodically blow off their outer layers

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the expelled gas expands outward away

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from the star forming a bubble or shell

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around the star

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sometimes the envelope of debris holds

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clumps of dense gas that shine like the

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the term planetary nebula is misleading

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it comes from late 18th century

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astronomers who thought their rounded

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shape looked similar to planets and

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telescopes of that time

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they named them planetary nebulae as a

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result

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supernova remnants are the diffused

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clouds of expanding debris released by a

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massive star's death explosion

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the cygnus loop is a vast expanding 110

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light year wide supernova remnant

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it is so large that hubble can only

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some supernova remnants emit their light

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from a shell of shocked material

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others like the crab nebula emit most of

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their light from within the expanding

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shell

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and still other supernova remnants shine

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as a combination of the two

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nebulae are some of the most resplendent

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objects in the universe

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and thanks to the hubble space telescope