WEBVTT

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<v Speaker 1>Welcome to Bedtime Astronomy. Explore the wonders of the cosmos

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<v Speaker 1>with our soothing Bedtime Astronomy podcast. Each episode offers a

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<v Speaker 1>gentle journey through the stars, planets, and beyond, perfect for

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<v Speaker 1>unwinding after a long day. Let's travel through the mysteries

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<v Speaker 1>of the universe as you drift off into a peaceful

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<v Speaker 1>slumber under the night sky. This week in Astronomy, milky

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<v Speaker 1>Way's Core Planet nine and first molecule magnetic map reveals

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<v Speaker 1>secrets of Milky Way's core. At the very center of

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<v Speaker 1>our Milky Way Galaxy is a wild and mysterious area

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<v Speaker 1>full of swirling gas, stars being born, and strong forces

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<v Speaker 1>we can't normally see. Scientists have just created the first

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<v Speaker 1>detailed map of the magnetic fields in this chaotic region,

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<v Speaker 1>giving us new clues about how stars are formed and

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<v Speaker 1>how they grow in such intense conditions. This research was

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<v Speaker 1>led by a PhD student named Roygoo from the University

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<v Speaker 1>of Chicago. He and his team focused on a part

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<v Speaker 1>of space near the galaxies core known as Sagittarius Sea.

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<v Speaker 1>This area is packed with dense gas clouds and powerful forces,

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<v Speaker 1>and it plays a key role in helping scientists understand

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<v Speaker 1>how everything in the middle of the galaxy fits together.

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<v Speaker 1>Think of it as a cosmic decoder, like a Rosetta stone,

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<v Speaker 1>helping us understand complex galactic behavior. To look into this

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<v Speaker 1>mysterious place, the scientists used a special telescope called Sophia,

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<v Speaker 1>which was mounted on an airplane and could study light

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<v Speaker 1>in the infrared range before it was retired. This kind

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<v Speaker 1>of light is created by tiny particles of dust floating

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<v Speaker 1>through space. These dust grains are very small, but they

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<v Speaker 1>act like tiny compass needles. They line up with invisible

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<v Speaker 1>magnetic field lines, and the light they give off tell

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<v Speaker 1>scientists how those fields are shaped and where they go.

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<v Speaker 1>What they found was fascinating. The magnetic fields are wrapped

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<v Speaker 1>around a giant bubble of hot gas. This bubble was

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<v Speaker 1>pushed outward by strong winds coming from a group of

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<v Speaker 1>massive young stars. These stars blow out so much energy

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<v Speaker 1>that they create a sore of shell of gas and

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<v Speaker 1>magnetic field. This explains something that has puzzled scientists for

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<v Speaker 1>a long time, strange narrow streams of fast moving electrons

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<v Speaker 1>that shoot across space near the center of the galaxy.

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<v Speaker 1>These fast electron streams were first seen back in the

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<v Speaker 1>nineteen eighties by the same professor who now advises Royjau.

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<v Speaker 1>For years, no one was sure where they came from.

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<v Speaker 1>But with these new magnetic field maps, scientists now have

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<v Speaker 1>evidence that these streams are created when magnetic field lines

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<v Speaker 1>snap and reconnect with each other. This action launches Parkles

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<v Speaker 1>to almost the speed of light. The research gives us

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<v Speaker 1>a clearer picture of how everything in this part of

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<v Speaker 1>the galaxy works together. Cold gas where stars are born,

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<v Speaker 1>hot regions filled with ionized particles, and the strong magnetic

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<v Speaker 1>fields are all linked. They interact in a kind of

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<v Speaker 1>cosmic dance that controls how matter behaves and changes over

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<v Speaker 1>time in the center of the Milky Way. One of

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<v Speaker 1>the most surprising things was how well this study matched

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<v Speaker 1>with earlier studies using different tools. For example, the edges

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<v Speaker 1>of the magnetic fields matched perfectly with the locations where

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<v Speaker 1>scientists had found glowing carbon in another survey. They also

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<v Speaker 1>found that a very powerful and rare kind of star

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<v Speaker 1>called the wolf rayet star was sitting right in the

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<v Speaker 1>middle of this expanding bubble. This kind of research doesn't

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<v Speaker 1>just help us understand our own galaxy. It helps scientists

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<v Speaker 1>understand how galaxies everywhere in the universe form stars and

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<v Speaker 1>organize their matter. By studying this one extreme part of

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<v Speaker 1>the Milky Way, we're learning about the rules of the

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<v Speaker 1>Union verse itself, how stars are born, how they grow

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<v Speaker 1>in wild places, and how invisible forces like magnetic field

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<v Speaker 1>shape everything we see. The hunt for Planet nine, some

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<v Speaker 1>scientists think there might be a large hidden planet far

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<v Speaker 1>out beyond Neptune in our Solar system. This idea isn't new,

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<v Speaker 1>people were already wondering about it before Pluto was even

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<v Speaker 1>discovered in the nineteen thirties. Back then, astronomers noticed that

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<v Speaker 1>Uranus was at orbiting exactly the way it should based

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<v Speaker 1>on what the laws of physics predict. They thought maybe

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<v Speaker 1>an unknown planet much bigger than Earth was pulling on

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<v Speaker 1>Uranus with its gravity and messing up its path. Later on,

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<v Speaker 1>scientists figured out that this strange orbit was actually due

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<v Speaker 1>to an error in calculating Neptune's mass, and the mystery

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<v Speaker 1>seened solved. But in twenty sixteen, two scientists at Caltech,

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<v Speaker 1>Constantine Badegen and Mike Brown, came up with a new idea.

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<v Speaker 1>They believe there might still be another large planet, what

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<v Speaker 1>they called Planet nine, based on how objects in the

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<v Speaker 1>Kuiper Belt move The Kuiper Belt is a huge area

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<v Speaker 1>beyond Neptune, filled with small, icy worlds, asteroids, and dwarf planets,

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<v Speaker 1>including Pluto. These objects in the Kuiper Belt don't orbit

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<v Speaker 1>the Sun and neat expected paths. Instead, many of them

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<v Speaker 1>seem to follow odd, stretched out paths that suggests something

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<v Speaker 1>big is tugging on them. Bat Egen and Brown suggested

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<v Speaker 1>that this something might be a large, hidden planet far

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<v Speaker 1>beyond Neptune. They compared it to the way the Moon moves.

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<v Speaker 1>The Moon orbits Earth, and together they both orbit the

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<v Speaker 1>Sun from far away. The Moon's path looks like a

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<v Speaker 1>spiral because it's being pulled by both Earth and the Sun. Similarly,

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<v Speaker 1>objects in the Kuiper Belt might be getting pulled not

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<v Speaker 1>just by the Sun but also by this mysterious planet nine.

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<v Speaker 1>At first, not everyone agreed with this theory, but over

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<v Speaker 1>time scientists started noticing more strange movements in these distant objects,

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<v Speaker 1>and those observations seemed to support the idea of a

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<v Speaker 1>hidden planet. In twenty twenty four, Brown even said he

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<v Speaker 1>believed Planet nine almost certainly exists because nothing else fully

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<v Speaker 1>explains what scientists are seeing. In twenty eighteen, a new

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<v Speaker 1>object called two zero one seven of two oh one

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<v Speaker 1>was found. It's a small world, about seven hundred kilometers wide,

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<v Speaker 1>with a very stretched out orbit around the Sun. Its

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<v Speaker 1>weird path might have been caused by a collision or

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<v Speaker 1>by the pull of Planet nine. Still, there are problems

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<v Speaker 1>with the theory. If Planet nine is real, why haven't

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<v Speaker 1>we seen it yet. Some scientists think we just don't

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<v Speaker 1>have enough data to say for sure. Others suggest different

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<v Speaker 1>causes for the strange orbits, like a ring of space

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<v Speaker 1>debris or even a small black hole. One of the

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<v Speaker 1>biggest challenges is that these objects take a really long

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<v Speaker 1>time to orbit the Sun. For example, twenty seventeen of

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<v Speaker 1>two oh one takes about twenty four thousand years to

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<v Speaker 1>complete one orbit. That means we haven't been watching them

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<v Speaker 1>long enough to clearly see the effects of another planet's gravity.

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<v Speaker 1>New discoveries have made things even more complicated. In twenty

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<v Speaker 1>twenty three, astronomers found another distant object called two zero

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<v Speaker 1>two three KQU fourteen. It's what scientists call a saidnoid,

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<v Speaker 1>which means it spends most of its time far away

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<v Speaker 1>from the Sun, in a zone where the Sun still

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<v Speaker 1>has some gravitational influence, it doesn't seem to be affected

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<v Speaker 1>much by Neptune, and its orbit is more stable than

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<v Speaker 1>some others. The fact that we've now found four of

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<v Speaker 1>these saidnoids, all with fairly stable orbits, raises questions. If

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<v Speaker 1>Planet nine is really out there pulling on things, we'd

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<v Speaker 1>expect more Chao movement, So if it exists, it must

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<v Speaker 1>be much farther away than we thought, maybe over five

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<v Speaker 1>hundred times farther from the Sun than Earth is. Finding

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<v Speaker 1>Planet nine is extremely hard. Even our fastest spacecraft would

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<v Speaker 1>take over one hundred years to reach the area where

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<v Speaker 1>it might be. For now, we have to rely on

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<v Speaker 1>powerful telescopes on Earth and in space to keep searching.

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<v Speaker 1>As we build better instruments and find more distant objects,

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<v Speaker 1>we might eventually discover something that confirms or disproves the

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<v Speaker 1>idea of planet nine. So the mystery continues, and it

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<v Speaker 1>could still take years to solve how the first molecule

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<v Speaker 1>helped stars form. Right after the Big Bang, which happened

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<v Speaker 1>about thirteen point eight billion years ago, the universe was

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<v Speaker 1>incredibly hot and dense, but in just a few seconds

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<v Speaker 1>it started cooling down. This cooling allowed the very first

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<v Speaker 1>elements to form hydrogen and helium. At first, these elements

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<v Speaker 1>were in a charged state and couldn't form complete atoms.

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<v Speaker 1>It took around three hundred and eighty thousand years for

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<v Speaker 1>the universe to cool enough for atoms to form when

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<v Speaker 1>electrons joined with these nuclei. This change made the universe

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<v Speaker 1>more stable and ready for the first chemical reactions to happen.

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<v Speaker 1>The first molecule ever formed in the universe was called

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<v Speaker 1>helium hydride written as helium hydride ion. It formed when

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<v Speaker 1>a helium atom combined with a positively charged hydrogen nucleus.

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<v Speaker 1>This molecule played a key role in starting the chain

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<v Speaker 1>of events that led to the creation of molecular hydrogen

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<v Speaker 1>or H two, which is the most common molecule in

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<v Speaker 1>the universe today. After atoms formed, the universe went through

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<v Speaker 1>what scientists call the Dark Age. During this time, there

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<v Speaker 1>were no stars or other light sources yet, so even

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<v Speaker 1>though space had become clear, it was still dark. It

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<v Speaker 1>took several hundred million years for the first stars to appear,

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<v Speaker 1>even though there was no light yet. Molecules like helium hydride,

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<v Speaker 1>ion and H two were important during this time for

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<v Speaker 1>stars to form clouds of gas had to shrink and

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<v Speaker 1>get hot enough for nuclear reactions to start, but this

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<v Speaker 1>only happens if the gas can lose some of its heat.

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<v Speaker 1>This heat is lost when atoms and molecules bump into

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<v Speaker 1>each other and release energy in the form of light.

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<v Speaker 1>When the temperature drops below about ten thousand degrees celsius,

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<v Speaker 1>hydrogen atoms don't release much energy this way anymore. Molecules

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<v Speaker 1>like helium hydride ion become especially helpful because they can

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<v Speaker 1>still give off energy by spinning and vibrating. Because of this,

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<v Speaker 1>scientists think helium hydride ion helped early gas clouds cool

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<v Speaker 1>down enough to form stars. The amount of this molecule

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<v Speaker 1>in the early universe may have made a big difference

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<v Speaker 1>in how easily stars could form. Helium hydride ion often

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<v Speaker 1>broke apart when it hit hydrogen atoms. This created neutral

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<v Speaker 1>helium atoms in another molecule, molecular hydrogen ion, which then

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<v Speaker 1>reacted again to form normal hydrogen molecules. All this helped

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<v Speaker 1>lead to more H two, which also helped with cooling

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<v Speaker 1>and star formation. Scientists in Germany at the Max Plank

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<v Speaker 1>Institute for Nuclear Physics managed to recreate one of these

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<v Speaker 1>early reactions instead of using normal hydrogen, they used a

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<v Speaker 1>special kind called deuterium, which is hydrogen with an extra

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<v Speaker 1>particle in its nucleus. When helium hydride ion reacts with deuterium,

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<v Speaker 1>it makes a different molecule called HD and a neutral

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<v Speaker 1>helium atom. This experiment was done in a special machine

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<v Speaker 1>called the cryogenic storage ring, which can simulate the cold

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<v Speaker 1>and empty conditions of space. The ring is about thirty

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<v Speaker 1>five meters wide and can hold ion particles for up

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<v Speaker 1>to sixty seconds. At very very low temperatures close to

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<v Speaker 1>absolute zero, the scientists shot beams of helium hydride ion

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<v Speaker 1>and deuterium at each other and measured how often they reacted.

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<v Speaker 1>They discovered that, unlike what earlier theories predicted, the reaction

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<v Speaker 1>didn't slow down at lower temperatures. It stayed steady. This

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<v Speaker 1>means the reaction between helium hydride ion and hydrogen or

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<v Speaker 1>deuterium was likely much more important in the early universe

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<v Speaker 1>than scientists had thought. This result also matches newer calculations

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<v Speaker 1>by other scientists who found mistakes in earlier models used

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<v Speaker 1>to predict this reaction. The updated models now agree with

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<v Speaker 1>what the experiment showed. Since molecules like helium hydride, ion,

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<v Speaker 1>and hydrogen were so important in helping the first stars form.

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<v Speaker 1>This new discovery gives us better insight into how the

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<v Speaker 1>very first stars may have been born. SMA