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  • So space is actually FULL of dust.

  • I'm talking about billowing pillars of dust extending over a BILLION kilometers in size.

  • But with all this cosmic dust floating around, how exactly do orbiting observatories, like the James Webb Space Telescope,

  • actually see through it?

  • Alright, first let's go over the basics of what cosmic dust actually is.

  • In contrast to your typical household dust bunnies,

  • cosmic dust is a collection of extremely tiny solid matter particles drifting around in space.

  • And I mean really, really, really small.

  • Like just a few molecules across.

  • You may be wondering: how much dust is there in the universe...

  • and where did it even come from?!

  • So here's the thingastronomers don't exactly know the answers to these questions.

  • BUT they do know that around 4,700 metric tons of dust falls onto Earth every year.

  • And they know that supernovas played a huge part in its production and distribution.

  • When Sun-like stars collapse and explode as a supernova,

  • the combined garble of elements contained in their dense cores are expelled into the universe.

  • These elements include helium, carbon, oxygen...and even iron in bigger stars.

  • Together, they form molecular clouds, with heavier elements like iron and silicon combining with oxygen to form minerals.

  • Those tiny mineral grains are what we refer to as…*ding, ding, ding* dust!

  • And this dust will never disappear because it's an essential key to planet and star formation.

  • Once dust is expelled from a star, it can travel to another part of the universe, create another star,

  • and at the end of that star's life, get expelled again.

  • And so the cycle of dust distribution continues.

  • Unfortunately, this recycled cosmic dust is often in the way for astronomers making their observations.

  • Because you see...cosmic dust particles are similar in size to shorter wavelengths of light,

  • like blue light, they have the ability to absorb or scatter those wavelengths.

  • Whereas longer wavelengths of light, like red light, pass directly through dust clouds

  • an effect known as Interstellar Reddening.

  • All the light that gets absorbed or scattered by the dust clouds makes stars tucked behind them seem more red and faint.

  • This means that the average human eye looking through a regular old telescope is no match for a dust cloud...

  • since most of the light reaching that telescope will be outside the visible light spectrum.

  • For many years this limited what astronomers could observe until William Herschel discovered infrared light in 1800,

  • opening a world of possibilities.

  • Modern observatories are utilizing the longer infrared wavelengths to see beyond the naked eye and through dust.

  • Observatories have even found water and other organic molecules on asteroids!

  • But now astronomers want to see in even greater detail.

  • And this is where the James Webb Space Telescope comes into play.

  • Webb can observe even longer infrared wavelengths and when paired with its advanced detectors,

  • this observatory can analyze a much wider range of light than observatories before it.

  • But Webb will be doing more than just looking through the dust, it might be able to help solve one major dust-related problem

  • called thedust budget crisis.”

  • This is the inability to account for all the dust found throughout the universe.

  • Webb will be working with JAXA to observe infrared light from Wolf-Rayet stars that help count it.

  • Wolf-Rayet Stars are super massive stars at a very late stage of stellar life.

  • When observed in infrared light, they've been seen releasing dust in a pinwheel pattern.

  • Like this one named WR 112, which astronomers call "a highly efficient dust factory.”

  • It's capable of producing the Earths' mass of dust in just one year!

  • Once Webb takes to the skies, it'll be able to observe the chemical signatures produced from Wolf-Rayet stars

  • that could provide us with a better understanding of not only early planet formation,

  • but also how the universe got so dusty.

  • Astronomers have come a long way in their quest to probe the dusty closet that is our universe,

  • and the hope is that James Webb will help clear the skies for many more years of space discovery.

  • If you love space as much as I do, be sure to subscribe to Seeker for all your latest updates

  • and check out this video here.

  • Thanks so much for watching and I'll see you next time.

So space is actually FULL of dust.

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