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humanity has always been drawn to the

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night sky we draw pictures in the Stars

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track the planets see signs importance

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and celestial objects but so much of the

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universe is beyond our reach

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vast distances separate us from the

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sites that might answer some of our

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biggest questions how do galaxies form

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how do stars and planets come to be do

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distant planets have the conditions

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necessary for life to construct and test

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our theories we need to see what's

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happening so we build tools to extend

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our vision they get bigger more powerful

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more advanced as time goes on astronomy

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stops relying on the light we can see

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when you look at the world here seeing

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something we call visible light but

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visible light is really only a certain

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form of radiation our universe is full

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of many different types of radiation it

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surrounds us our bodies evolved to

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detect visible light with our eyes but

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they also evolved to detect another kind

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of radiation called infrared light our

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bodies feel infrared light is heat this

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infrared radiation was discovered by the

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astronomer Frederick William Herschel

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Herschel knew that a prism could be used

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to break white light into colors he

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wanted to know whether the colors had

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different temperatures they did but then

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Herschel measured the empty space just

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beyond the red light though no sunlight

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was visible it was hot Herschel had just

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discovered invisible infrared radiation

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humanity now knew that there were forms

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of radiation that could not be seen they

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could be anywhere all around us how many

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were there what were they up to

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what were they hiding obviously we had

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to find out a type of energy that

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travels through the universe in the form

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of waves is called electromagnetic

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radiation the entire range of it from

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high-energy gamma rays to low energy

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radio waves is called the

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electromagnetic spectrum

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although our eyes can see only visible

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light we can build tools like infrared

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detecting cameras to see other forms of

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radiation these tools are man-made eyes

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that view invisible radiation for us and

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transform it into pictures

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objects can emit all kinds of radiation

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huh observing the entirety of that

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radiation gives us a true picture of an

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object when we turn these tools on space

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they open up the entire cosmos to us in

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its full glory when we look at the night

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sky we see stars and planets galaxies

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and nebulae in the form of visible light

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but if we could see in infrared light

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the sky would appear very different for

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one thing infrared lights long

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wavelengths penetrate clouds of gas and

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dust

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the shorter wavelengths of visible light

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are stopped and scattered as they fight

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through collections of particles so by

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detecting infrared light we can see

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through clouds of gas and dust to warm

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objects inside like just forming stars

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the objects that don't glow with any

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visible light of their own like planets

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are still often warm enough to radiate

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infrared light perhaps allowing us to

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glimpse them and by observing how

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infrared light from a planet star passes

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through its atmosphere we acquire clues

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about the planets composition the dust

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left behind by distant planets as they

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form will also glow in infrared helping

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to show us how planets are born so

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infrared helps us see objects like these

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in our own galactic backyard but it can

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also help us observe the first objects

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that formed in the universe after the

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Big Bang

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imagine you gave a letter to the post

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office and they galaxies billions of

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light years away and addressed it to

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earth it would travel for an incredibly

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long time when it finally arrived at its

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destination the person who opened it

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would be getting news from billions of

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years earlier the light from the first

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stars to shine in the universe is

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something like that

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it left the stars ages ago and is still

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out there in space traveling the vast

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distances between galaxies if we could

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see it we could see those galaxies as

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they were in the early universe

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essentially we would be seeing back in

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time but we haven't been able to see it

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why because the universe is expanding as

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light travels across space it's

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stretched like taffy by the expansion

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the first stars gave off mostly visible

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and ultraviolet light but the stretching

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changes those waves into infrared light

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this is called red shifting the only way

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to see that light as it arrives in our

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region of the universe is to look for

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that

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faint infrared glow by capturing it we

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will be able to create images of the

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first galaxies to form in the universe

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by witnessing the birth of the first

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stars and galaxies we deepen our

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knowledge of how the universe as we know

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it came to be how did we get from those

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first blazing stars to the islands of

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billions of stars we see today what will

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we learn about how galaxies grow and

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evolve

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how did the chaos of the early universe

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transform into order and structure NASA

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is currently building the James Webb

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Space Telescope with its huge infrared

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capturing mirror and distant orbit far

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beyond the moon Webb will allow us to

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view the cosmos as we've never seen it

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before Webb will search for signs of

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water vapor on planets around other

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stars it will take pictures of the

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universes infancy Webb will reveal the

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hidden stars and solar systems forming

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within cocoons of dust the answers to

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some of the universe's biggest mysteries

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and more questions we haven't thought to

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ask are waiting out there for us in the

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form of infrared radiation all we have

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to do is look