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This episode was made in partnership with The Kavli Prize. The Kavli Prize honors scientists for breakthroughs in astrophysics, nanoscience and neuroscience — transforming our understanding of the very big, the very small, and the very complex. To learn more about Andrew Fabian’s work, go to http://kavliprize.org/prizes-and-laureates/prizes/2020-kavli-prize-astrophysics.

The apparent void in the darkness of space is not as empty as you might think. In fact, it somehow holds the key to creating stars, planets, and even us! And Dutch super-scientist Ewine van Dishoeck made it her life's work to figure out how interstellar gas and dust turned into us.

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Sources:
http://kavliprize.org/sites/default/files/TKP%202018%20astro%20biographies.pdf
https://www.pnas.org/content/103/33/12229
https://www.pnas.org/content/115/28/7166
http://kavliprize.org/prizes-and-laureates/prizes/2018-kavli-prize-astrophysics
https://hypertextbook.com/facts/2000/DaWeiCai.shtml
https://www.europhysicsnews.org/articles/epn/pdf/2011/01/epn2011421p26.pdf
http://adsabs.harvard.edu/full/1986ApJS...62..109V
http://adsabs.harvard.edu/full/1987ApJ...322..412B
http://articles.adsabs.harvard.edu//full/1988ApJ...334..771V/0000771.000.html
https://arxiv.org/pdf/1411.5280.pdf
https://www.quantamagazine.org/ewine-van-dishoeck-the-netherlander-who-traced-waters-origin-20181101/


Image Sources:
https://commons.wikimedia.org/wiki/File:Ewine_van_Dishoeck.tif
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https://svs.gsfc.nasa.gov/13591
https://www.flickr.com/photos/kavliprize/43751152774/in/album-72157700663066244/
https://commons.wikimedia.org/wiki/File:Herschel_Space_Observatory.jpg
https://www.herschel.caltech.edu/image/nhsc2017-005a
https://svs.gsfc.nasa.gov/vis/a010000/a011000/a011087/
https://svs.gsfc.nasa.gov/vis/a010000/a010600/a010659/index.html
https://hubblesite.org/contents/media/images/1998/41/732-Image.html?itemsPerPage=100&page=2&keyword=stis&filterUUID=4c394bbb-b21e-43ab-a160-2a4521d70243
This episode was made in  partnership with the Kavli Prize.

The Kavli Prize honors scientists  for breakthroughs in astrophysics, nanoscience and neuroscience—transforming  our understanding of the very big, the very  small, and the very complex. [♪ INTRO]. It’s easy to be dazzled by all the  shiny, sparkling stuff in space… and fair enough—stars and  galaxies are great.

But the apparent void in  the dark spaces between them is not as empty as you might think. Most of what we think of as empty space  has between one and a few thousand atoms per square centimeter. That’s not much compared  to the 25 quintillion atoms in every square centimeter of the air we breathe.

But somehow, it’s enough to enable  the chemistry needed to make all the dazzling galaxies, stars,  and planets in the universe. It even made us. And the Dutch super-scientist  Ewine van Dishoeck has made it her life’s work to figure out how.

It’s not an easy thing to do—to  figure out how a thin soup of gas and dust turns into structures  like solar systems with thousands of different molecules and  the ingredients for life. For one, these thin clouds of molecules  are extremely difficult to study. Since they’re very cold, they  don’t emit much light of their own.

And they’re thin enough that  most light passes right through. But a few wavelengths of  light don’t make it through. Every atom and molecule absorbs  certain colors of light, so by looking at missing wavelengths, you  can tell what a cloud is made of.

And in the early 1900s, astronomers  began using this technique to discover lots of atoms and  molecules floating between stars. By the early ’70s, we even  had instruments that could look for these chemical signatures in space. So, it was a flourishing field  when van Dishoeck began her scientific studies around the  same time, and she found herself drawn to chemistry and space.

After her undergraduate  degree in chemistry in Leiden, in the Netherlands, she started  doing research at Harvard, as a PhD student and later a postdoc. Then she had brief stints as  faculty at Princeton and Caltech before returning to Leiden in 1990. All the while, she was trying to home  in on the answer to one question:.

How does interstellar gas and dust turn into us? One key part of the equation is carbon. Life as we know it depends on  this element, and fortunately, space is full of it!

It’s usually locked up in  the form of carbon monoxide, which can combine with other  molecules to make the carbon chains that form the basis of life. Scientists understood this by the  1980s, but there was a conundrum:. From lab studies, it was clear  that carbon monoxide is easily destroyed by UV light, which breaks  the bonds that hold it together.

And thanks to hot, bright stars,  there’s plenty of UV light in galaxies. But somehow, carbon monoxide manages  to survive—and no one quite knew why. So, fresh from her PhD, van  Dishoeck took on this problem.

She created theoretical models  of interstellar clouds in the lab and then validated those models against real observations. And she started to see what was going on. The key was in the colors  that were missing from light passing through these clouds.

Carbon monoxide isn’t  vulnerable to all UV light —just the wavelengths that it can absorb. Those are the ones that rupture  its bonds and break it apart. But if light at those wavelengths  hits something else first, then it can’t do any more damage.

In 1982, astronomers had shown that  the molecules of carbon monoxide on the edge of the cloud absorb  some of the damaging light, protecting the molecules further in. Later that decade, van Dishoeck  and her collaborator John Black found that other molecules,  as well as dust, can absorb some of these same wavelengths  and also protect carbon monoxide from being destroyed. And in 1988, they combined these  findings into a now-famous paper that solved the carbon monoxide conundrum.

The paper demonstrated that, thanks  to protection from other particles in its environment, carbon  monoxide could survive in the midst of destructive radiation. And that’s how it stuck around  long enough to lend itself to life! But that’s not the only way that life  is rooted in these molecular clouds.

Aside from carbon, one of the other  key ingredients to life is water. And that’s also floating around between the stars. The problem is, we have so much  of it in our own atmosphere that it’s hard to detect from the ground.

But starting in the 1990s, space  telescopes finally made it possible. Van Dishoeck was instrumental  in analyzing data from the Infrared Space Observatory  and Herschel Space Observatory, which were among the first to  look for interstellar water. And this research showed that  these loose molecules of water play a surprisingly important role in  the process of star formation.

Out in frigid interstellar space,  most of the water is frozen solid. And when it encounters dust  particles, it attaches to the surface of that dust, making the dust both stickier and heavier. Now that they’re more massive,  those dust grains attract more material, setting off  a runaway process of growth.

As matter accumulates in a  cloud, the region gets hotter and denser until it can start fusing hydrogen. And that is how a star is born. Van Dishoeck also took this a  step further and showed that, many millions of years later,  this same process also plays a central role in planet formation.

Once again, water makes dust grains  sticky and helps bring matter together until there’s enough for a planet. So, while we might have known  that we owe a lot of our existence to water—the role of water goes back further than many scientists expected. These fundamental discoveries  about water and carbon monoxide are just two examples of Van  Dishoeck’s incredible efforts to understand our cosmic origins.

She is the co-author of nearly 500 publications and peer-reviewed papers, with  around 58 thousand citations. In 2018, she was elected president of  the International Astronomical Union. And that same year, she was  awarded the prestigious Kavli Prize in Astrophysics for her  incredible discoveries and her foundational role in the field of astrochemistry.

The Kavli Prize honors  scientists for breakthroughs in astrophysics, nanoscience, and neuroscience. The winners have made outstanding  progress in understanding the very big to the very small. They are transforming our  knowledge of the world we live in.

If you’d like to learn more  about Ewine van Dishoeck, you can click the link in the  description to visit her page on the Kavli Prize website. You can also learn about the winner  of the 2020 prize in Astrophysics, awarded to Andrew Fabian, who  made many discoveries, including a black hole that makes the deepest  sound in the known universe. To hear his story, head over  to SciShow Space and check out the video we just posted there! [♪ OUTRO].