A New View of the Milky Way, Akatsuki's Legacy, and How to Spot Comet Lemmon

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Avery: Welcome to Astronomy Daily, the podcast that

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brings you the universe one story at a time.

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I'm Avery.

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Anna: And I'm Anna. It's great to be with you

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today. Today we have a packed show.

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We'll be looking at a stunning new image of

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our own Milky Way, saying a, ah, fond

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farewell to a Venus orbiter and telling you

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how to spot a comet visiting our skies.

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Avery: Plus, we'll cover China's ambitious plans for

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the Moon.

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Anna: And.

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Avery: And a fascinating discovery about the very

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first stars in the universe were born. So

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let's jump right in.

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Anna, where are we starting?

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Anna: Let's start close to home, Avery. With

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a view of our galaxy like we've never seen

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before. Astronomers have just released a

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milestone new image of the Milky Way, and

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it's absolutely breathtaking.

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Avery: I've seen it, and it really is something

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else. This isn't a typical photograph,

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though, is it? This was captured using a

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radio telescope array in Western Australia.

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Anna: That's right. It's a low frequency

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radio image from the Murchison Wide Field

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Array. Think of it as seeing the galaxy in a

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completely different kind of light. Instead

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of starlight, we're seeing the radio waves

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emitted by cosmic rays, hot gas, and

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other energetic phenomena.

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Avery: So it peels back the curtain in a way. The

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dust clouds that block our view in visible

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light are transparent to these radio waves,

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right?

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Anna: Exactly. This new survey gives us an

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unprecedented view of the entire southern

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galactic plane. For the first time, we have

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a deep, wide image at these low

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frequencies. And the level of detail is

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incredible. The team has been able to catalog

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over 3,000 supernova remnants,

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the expanding shells of exploded stars.

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Avery: 3,000. That's a huge jump in our census

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of stellar deaths. And it's not just about

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endings, is it? It also shows us where new

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star born.

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Anna: It does. We can see stellar

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nurseries, vast clouds of gas and dust that

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are just beginning to collapse and form new

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suns and planets. By studying the galaxy

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in this way, we can better understand the

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entire life cycle of stars, from birth

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in these nurseries to their often

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violent deaths as supernovae. It's a

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true milestone for radio astronomy.

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Avery: Incredible. From the life of stars to the end

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of a mission.

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On a more somber note, we have to say goodbye

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to a very tenacious spacecraft.

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Anna: Yes, unfortunately,

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jaxa, the Japanese space agency,

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has officially declared its Akatsuki

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spacecraft as dead. It was orbiting Venus,

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and for a while, it was the only active

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mission at our sister planet.

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Avery: I remember its story. It had such a dramatic

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journey. It didn't make it into orbit on the

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first try. Did it?

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Anna: Not at all. Its main engine failed during

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the orbital insertion burn back in 2010

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and flew right past Venus. The team

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had to put it into a holding pattern,

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orbiting the sun for five years. Then,

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in a brilliant feat of engineering, they used

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its smaller thrusters to make a second

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successful attempt to enter orbit in 2015.

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Avery: Just an amazing comeback story for a robotic

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probe. And it delivered some fantastic

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science for nearly a decade after that.

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Anna: It really did. Akatsuki

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completely revolutionized our understanding

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of Venus's climate. Its biggest contribution

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was studying the planet's super

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rotation, a phenomenon where the atmosphere

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whips around the planet 60 times faster

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than the planet itself rotates. The probe's

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infrared cameras tracked cloud movements and

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helped us understand the dynamics driving

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those extreme winds.

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Avery: A, true testament to the ingenuity of its

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mission controllers. It's sad to see it go,

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and it leaves a temporary void in our

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exploration of Venus.

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Anna: It is.

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But let's turn from a world we can't visit

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to a visitor you can see in our own skies.

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Avery, it's comet watching season.

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Avery: It certainly is. Observers in the Northern

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Hemisphere have a chance to spot Comet C

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2025 A6, also known as

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Comet Lemmon. It's currently making its way

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through the inner solar system and is putting

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on a nice little show.

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Anna: So how can our listeners find it?

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Avery: The best time to look is shortly after

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sunset. You'll want to find a spot with a

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clear view of the western horizon, away from

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city lights, if you can. It made its closest

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approach to Earth on October 21, and

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it will reach its closest point to the sun on

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November eight. So it's right in its prime

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viewing window.

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Anna: Now, will you need a telescope?

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Avery: It might just be bright enough to be visible

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to the naked eye under very dark skies,

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but a good pair of binoculars is your best

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bet. You'll be looking for a small, fuzzy

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patch of light, maybe with a fake tail.

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Anna: And this is a special visitor.

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Comet LEMMON is a long period comet, which

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means it comes from the Oort Cloud, the most

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distant and icy region of our solar system.

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And after it rounds the sun, it's going to be

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flung back out into.

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Avery: Deep space, and it won't be back for

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another 1154

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years. So, as you said, Anna, this is your

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one and only chance to see it. Don't miss it.

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Anna: From a fleeting visitor to a more permanent

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destination. The world's space agencies

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are looking to the future, and a big part of

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that future is a return to the Moon.

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Avery: That's right. And this week, China reiterated

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its Ambitious goal to land their astronauts

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on the lunar surface by 2030. Officials

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confirmed that everything is moving forward

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on schedule.

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Anna: This isn't just talk. They're developing some

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serious hardware. They mentioned that the new

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super heavy lift rocket, the long March

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10th is progressing smoothly. That's the

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rocket powerful enough to send the crew and

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lander to the moon.

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Avery: They also said the development of the lander

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itself, the lunar rover and the new moon

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landing suits are all well underway. The

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announcement came at ah, the same time they

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introduced the next crew heading to their

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Tiangong Space Station, which really

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highlights how their human spaceflight

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program is operating at a very high tempo.

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The crew for China's next manned flight to

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the Tiangong Space Station will include the

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country's youngest ever astronaut to

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undertake a space mission, as well as four

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lab mice.

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Anna: The Shenzhou 21 mission is set to blast

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off at 11:44pm M on Friday

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15:44 GMT from the Zhuquan

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Satellite Launch center in northwest China.

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Avery: This crew will be led by veteran space pilot

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Zhang Liu, who took part in the Shenzhou 15

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mission more than two years ago. He will lead

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payload specialist Zhang Hongsheng and flight

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engineer Wu Fei on their first space flight.

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Anna: Wu, who has just turned 32, is

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set to become the youngest Chinese astronaut

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to undertake a space mission to date.

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Avery: Also along for the ride are four mice, two

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male and two female, which will be the

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subjects of China's first in orbit

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experiments on rodents.

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Anna: It certainly feels like we're entering a new

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era of lunar exploration with multiple

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countries aiming for the Moon this decade.

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It's going to be a very exciting few years.

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Avery: Definitely.

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For our final story, Anna, let's go from the

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future of spaceflight to the most distant

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past, all the way back to the universe's

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cosmic dawn.

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Anna: It's a fascinating story. A new study is

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providing strong evidence that the very first

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stars in the UniverseWhat astronomers call

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Population 3 stars were commonly

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born in pairs.

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Avery: Born in pairs? That's incredible. How on

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Earth can astronomers figure that out,

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looking back over 13 billion years?

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Anna: Well, we can't observe those first stars

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directly. They were too massive and short

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lived. So scientists have to be clever.

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They used the Very Large Telescope in Chile

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to study stars in the Small Magellanic Cloud,

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a nearby dwarf galaxy.

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Avery: Okay, but how does that help? Those aren't

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population three stars.

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Anna: They aren't. But the Small Magellanic Cloud

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has very low metallicity. That's

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the astronomical term for any element heavier

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than hydrogen and helium. Its chemical

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environment is much closer to the pristine

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conditions of the early universe than our own

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Milky Way is.

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Avery: So these stars are like a local analog, a

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window into how stars formed when heavy

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elements were scarce.

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Anna: Precisely. And what the researchers found

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was striking. By observing the most

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massive stars in this low metallicity

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environment, they discovered that at least

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70% of them are in close

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binary systems orbiting a, companion

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star.

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Avery: Wow. 70%. That's not

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a coincidence.

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Anna: Not at all. It provides the

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strongest observational evidence to date

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that the first massive stars in the universe

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were also primarily born as twins

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or in multiple star systems.

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This has huge implications for

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understanding how early galaxies evolved,

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how the first black holes were formed, and

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how the universe was seeded with the heavy

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elements that eventually made life like us

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possible.

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Avery: A, truly fundamental discovery.

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And that's all the time we have for this

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episode of Astronomy Daily. From our own

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galactic backyard to the dawn of time, it's

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been another busy week in the cosmos.

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Anna: It certainly has. Thank you so much for

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joining us. We'll be back next time with more

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of the latest news from across the universe.

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Avery: Until then, this is Avery reminding you to

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keep looking up