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Speaker 1: Welcome to Brainstuff, a production of iHeartRadio.

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Speaker 2: Hey brain Stuff, Lauren vogel Bomb here with another classic

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Speaker 2: episode from the archives. This one gets into astronomy research

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Speaker 2: that has let us learn more about the shape of

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Speaker 2: our Milky Way galaxy and why it's bent like a

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Speaker 2: damaged vinyl record. Hey rain Stuff, Lauren vogel Bomb here.

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Speaker 2: Imagine standing in a dense woodland. How would you know

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Speaker 2: the size and shape of that forest? From your limited viewpoint?

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Speaker 1: Not seeing the woods for the trees is a good

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Speaker 1: analogy for what astronomer's experience when trying to assess the

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Speaker 1: shape and size of our Milky Way galaxy. We occupy

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Speaker 1: a small star system embedded inside the Milky Way's disc.

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Speaker 1: It's not like we can fly above the galactic plane

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Speaker 1: to peak at our galaxies overall shape, although how cool

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Speaker 1: would that be. Our researchers, however, were determined to figure

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Speaker 1: out the true shape of the Milky Way while staying

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Speaker 1: embedded inside of it, and they have. Here's how they

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Speaker 1: did it. A team from the National Astronomical Observance Tories

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Speaker 1: of the Chinese Academy of Sciences that's the NAOC and

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Speaker 1: Macquarie University in Australia studied the one thousand, three hundred

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Speaker 1: and thirty nine bright pulsating stars called Cepheid variables to

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Speaker 1: create a three D map of the disc of our galaxy.

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Speaker 1: What they found came as a surprise. We live in

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Speaker 1: a warped galaxy. Astronomer and research collaborator Richard de Grace

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Speaker 1: said in a statement, Oh, we usually think of spiral

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Speaker 1: galaxies as being quite flat, like Andromeda, which you can

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Speaker 1: easily see through a telescope. But our galaxy isn't like Andromeda.

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Speaker 1: It has an S shaped bend that gets more twisted

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Speaker 1: the farther you move away from the galactic center. At

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Speaker 1: this bend, the galaxy's gravitational poll becomes weaker, making it

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Speaker 1: look like an old vinyl record that's become warped. The study,

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Speaker 1: which has been published in the journal Nature Astronomy, used

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Speaker 1: data from NASA's Wide Field Infrared Survey Explorer to precisely

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Speaker 1: determine the locations of the cepheids throughout our galactic disc

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Speaker 1: and turned them into a powerful tool to cut through

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Speaker 1: the dust, gas, and other stars that are obscuring our view.

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Speaker 1: Chen Xiadienne RENAOC and the lead author of the study,

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Speaker 1: said in a press release, it's notoriously difficult to determine

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Speaker 1: distances from the Sun two parts of the Milky Way's

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Speaker 1: added gas disc without having a clear idea of what

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Speaker 1: the disc actually looks like. However, we recently published a

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Speaker 1: new catalog of well behaved variable stars known as classical cepheids,

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Speaker 1: for which distances as accurate as three to five percent

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Speaker 1: can be determined. Cepheids are young stars that are four

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Speaker 1: to twenty times the mass of our Sun, and they

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Speaker 1: live fast and die young, consuming all their fuel in

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Speaker 1: the span of only a few million years, all while

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Speaker 1: burning up to one hundred thousand times brighter than our star.

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Speaker 1: But what they lack in life span they make up

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Speaker 1: or in regular pulses in brightness that can be used

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Speaker 1: by astronomers to accurately measure their distances, and in this case,

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Speaker 1: they acted as tracers to map out the warped milky

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Speaker 1: Way disc. Although the milky Way doesn't conform to the

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Speaker 1: standard flat disc exhibited by other spiral galaxies like Andromeda,

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Speaker 1: it's not alone. From earlier observations, the researchers identified a

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Speaker 1: dozen other galaxies with a similar S shaped bend, which

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Speaker 1: have given them a clue as to why our galaxy

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Speaker 1: is warped. Blue Chow, co author of the study, said,

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Speaker 1: combining our results with those other observations, we concluded that

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Speaker 1: Milky Way's warped spiral pattern is most likely caused by

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Speaker 1: torques or rotational forcing by the massive inner disc. Basically,

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Speaker 1: the orbital motions in the massive central region of the

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Speaker 1: Milky Way gravitationally bully the less massive outer regions, causing

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Speaker 1: them to buckle and bend out of shape. Ultimately, this

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Speaker 1: new finding could help us better understand the dynamics of

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Speaker 1: orbital motions inside the Milky Way, thereby providing a glimpse

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Speaker 1: of how our galaxy evolved. Today's episode is based on

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Speaker 1: the article our Milky Way is Warped Like an old

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Speaker 1: Vinyl record on HowStuffWorks dot.

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Speaker 2: Com, written by Ian O'Neil. Brain Stuff is production by

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Speaker 2: Heart Radio in partnership with how Stuffworks dot Com and

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Speaker 2: is produced by Tyler Klaang. Four more podcasts my heart Radio,

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Speaker 2: visit the iHeartRadio app, Apple Podcasts, or wherever you listen

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