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Howdy Stargazers and welcome to this episode of Star Trails.

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I'm Drew and I'll be your guide to the night sky for the week starting February 9th through

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the 15th.

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This week we're rolling back the clock to 1990 when Voyager 1 looked back and captured

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its final series of images, an poignant family portrait of our solar system.

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Also in last week's episode we examined the scale of time as it relates to the vast age

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of our universe.

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This week we're bringing the nearly unimaginable size of our universe into perspective.

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But first let's start with what you can see from your backyard this week.

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So grab a comfortable spot under the night sky and let's get started.

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Tonight the moon will be in its waxing gibbous phase, about 90% illuminated.

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This phase continues until the full moon on February 12th, known as the snow moon.

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We'll end the week in a waning gibbous phase.

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The snow moon is the traditional name for the full moon that occurs in February.

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The name originates from Native American Anglo-Saxon and European folklore, recognizing February

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as the month with the heaviest snowfall in the Northern Hemisphere.

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In many regions February is the coldest and harshest time of the year making the snow

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moon a fitting title for this celestial event.

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Interestingly this moon took on some unique names in other cultures.

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It's been called the Hunger Moon by many Native American tribes, particularly the Algonquin,

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because harsh winter conditions made hunting difficult.

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For similar reasons it's also known as the Bony Moon or Little Famine Moon in some indigenous

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cultures.

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Some tribes such as the Cree call it the Bear Moon because February marks the time when

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bear cubs are typically born in their dens.

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While this moon will wash out dimmer objects this week, the planets are still putting on

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a show.

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Venus shines brilliantly in the western sky after sunset.

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It will reach its peak brightness on the 16th making it a stunning evening star throughout

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our week.

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Mars is visible in the evening sky and will have a close encounter with the moon tonight.

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Look towards the east after sunset to witness this conjunction near the twin stars of Gemini,

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Caster and Pollux.

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Jupiter continues dominating the early evening sky.

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It can be seen high overhead after sunset and it's visible until the early morning.

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Saturn is still visible in the western sky after sunset, but it's gradually descending

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towards the horizon.

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It will become more difficult to observe in the coming weeks.

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I always like to make note of some of the lesser known constellations.

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We've covered winter favorites like Gemini and Orion extensively in recent episodes.

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So this week I thought we'd look at two whimsical constellations, Camelopartilus and Montserros.

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Camelopartilus, the giraffe, is a large but faint constellation that sprawls across the

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northern sky.

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Despite its size, it has no particularly bright stars making it difficult to spot with the

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naked eye.

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Its name comes from the Latin words for camel and leopard as ancient observers thought giraffes

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resembled a mix of these two animals.

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This constellation is home to NGC 2403, a spiral galaxy that resembles a miniature version

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of the Andromeda galaxy.

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This galaxy is around 8 million light years away and is visible in small telescopes.

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Binocular observers may want to track down Kimball's Cascade, a string of stars forming

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a diagonal line.

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Across the sky we find Montserros, the unicorn, a dim but fascinating constellation located

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between Orion, Canis Major and Gemini.

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It was first documented in the 17th century and lacks bright stars, making it challenging

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to locate without a star chart.

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This constellation is home to the Rosette Nebula.

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This massive region of ionized hydrogen gas is home to a young open cluster of stars.

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It's best seen with astrophotography or in large telescopes, but a faint glow can sometimes

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be seen through binoculars.

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This region also contains the Christmas tree cluster, an open star cluster shaped like a

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holiday tree.

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Also, be on the lookout for Beta monoceratis, a triple star system that can be resolved in

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a small telescope.

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Although the bright moon this week may hamper observations, these two constellations offer

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up some nice targets when skies are darker.

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Do you remember where you were on February 14th, 1990?

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I was a freshman in high school.

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Maybe some of you weren't born yet.

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On that date, Voyager 1 took a family photo of our solar system.

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While some folks were celebrating Valentine's Day, for those who look up to the cosmos,

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that day marked something truly extraordinary.

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Humanity captured an image that changed how we see ourselves.

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The image is a mosaic of our solar system.

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One frame in particular would go on to become iconic, the pale blue dot.

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From a distance of about 3.7 billion miles, Earth appeared as a tiny speck, less than

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a pixel in size, suspended in a beam of scattered sunlight.

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It showed how small and fragile our planet looked, just a faint dot adrift in the vast

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cosmic ocean.

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The idea for the image was proposed by Carl Sagan, who believed this portrait of our solar

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system could be a profound reminder of our place in the cosmos.

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In his now famous words, Sagan described Earth as a mode of dust suspended in a sunbeam,

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reminding us that everything we've ever known, all of human history, every triumph and tragedy,

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has unfolded on that tiny dot.

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Consider again that dot.

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That's here.

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That's home.

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That's us.

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Everyone it, everyone you love, everyone you know, everyone you ever heard of, every human

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being, whoever was, lived out their lives on a mode of dust suspended in a sunbeam.

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As Voyager 1 prepared to leave the solar system, NASA engineers sent a command to the spacecraft

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to turn its camera around and take one last look back, capturing six of the solar system's

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planets.

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Uranus, Earth, Jupiter, Saturn, Uranus and Neptune.

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Mercury was too close to the sun to be seen and Mars didn't make the cut due to unfavorable

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lighting conditions.

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The sun itself had to be carefully managed in the image to avoid damaging Voyager's sensitive

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camera.

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This resulted in an unintended consequence.

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Earth appeared an array of scattered sunlight, a cosmic coincidence that gives the photo

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an almost spiritual quality.

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Earth is tiny in this mosaic, barely larger than a tenth of a pixel in the rendering.

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From a distance of 3.7 billion miles, Voyager's camera had to use a narrow angle lens and

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extreme precision to even spot Earth in the void.

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The photo was taken with three color filters, blue, green and violet.

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These were combined to create the final image.

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The result wasn't about vibrant detail, it was about perspective.

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Earth's faint presence emphasized just how vast and dark space truly is.

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The full family portrait also holds symbolic weight.

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It's the only time in history that we've captured an image of the solar system in this

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way.

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By 1990, Voyager 1, now years past its mission to study Jupiter and Saturn, was speeding

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out of the solar system at nearly 40,000 miles per hour.

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And this was its final look back before its camera was permanently turned off to conserve

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power.

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While the pale blue dot is the most famous image from the mosaic, each frame tells a

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story.

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Saturn, for instance, appeared as a soft golden orb surrounded by its majestic rings.

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Jupiter, with its immense size, dominated its frame.

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And Neptune and Uranus, captured as faint, icy blue dots, hinted at the mysteries of

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the outer planets.

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Today, Voyager 1 is the farthest human-made object from Earth, carrying its golden record

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as a message for any intelligent life it might encounter.

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And yet, its most powerful legacy might be that small image of Earth.

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With that, let's take a journey from our tiny corner of the solar system to the edge

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of the observable universe, and learn more about scale and the vastness of our galaxy

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and the universe itself.

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Before we start, let's talk about why scale is important.

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Imagine the sun is the size of a grapefruit.

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If that's the case, how far away do you think Earth would be?

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At this scale, Earth would be a tiny grain of sand about 50 feet away.

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That's the length of a school bus.

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And Neptune, the farthest planet from the sun, would be a marble 1500 feet away, a little

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more than a quarter of a mile.

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This analogy shows just how much empty space there is in our solar system.

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And believe it or not, this is just the beginning of the story.

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The universe is so vast that even astronomers struggle to wrap their heads around it.

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So let's start small and work our way up.

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Let's begin close to home.

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Our solar system.

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At the center is the sun, a star so massive that it makes up 99.8% of the solar system's

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total mass.

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It's about 864,000 miles across.

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That's so big you could fit 1.3 million Earths inside of it.

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The Earth orbits the sun at an average distance of 93 million miles.

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We call this distance one astronomical unit, or AU.

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But here's where it gets wild.

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Neptune, the farthest planet from the sun, is 30 AU away.

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That's 2.8 billion miles.

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And here's another way to think about it.

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Light from the sun takes 8 minutes to reach Earth, but it takes more than 4 hours to reach

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Neptune.

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That means when you look at Neptune through a telescope, you're seeing it as it was

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4 hours ago.

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And that's just within our solar system.

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Now let's zoom out a bit.

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The nearest star to our sun is Proxima Centauri, part of the Alpha Centauri system.

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It's 4.24 light years away.

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That's 25 trillion miles.

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To put that in perspective, if the sun were a grapefruit in New York City, Proxima Centauri

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would be another grapefruit in Los Angeles.

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That's how much empty space there is between stars.

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And Proxima Centauri is just our next door neighbor.

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For a galaxy, the Milky Way contains 100 to 400 billion stars, and it's about 100,000

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light years across.

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Our solar system is located in one of the Milky Way's spiral arms, about 27,000 light

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years from the galactic center.

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If the Milky Way were the size of a football field, our solar system would be a tiny speck

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on the 10-yard line.

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Of course, the Milky Way is just one galaxy among billions.

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Our nearest galactic neighbor is the Andromeda Galaxy, which is 2.5 million light years away.

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That means the light we see from Andromeda today left around the time early humans were

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first walking the Earth.

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Andromeda is part of a small group of galaxies called the Local Group, which includes about

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54 galaxies.

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But even the Local Group is just a tiny part of a much larger structure called the Virgo

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Supercluster, which contains more than 100 galaxy groups and spans 110 million light years.

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And here's the kicker.

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The Virgo Supercluster is just one of countless superclusters in the universe.

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These superclusters form a vast cosmic web, with galaxies strung along filaments like pearls

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on a necklace.

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The scale is almost impossible to comprehend.

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Now, let's zoom out even further to the observable universe.

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This is the part of the universe we can see from Earth, and it's about 93 billion light

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years across.

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Scientists think the universe is around 13.8 billion years old, so how can the universe

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beat 93 billion light years across?

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Just because the universe is expanding, space itself is stretching, carrying galaxies along

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with it.

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So the light from distant galaxies has traveled much farther than we might expect.

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The observable universe contains an estimated 2 trillion galaxies, each with billions or

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even trillions of stars.

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If the observable universe were the size of Earth, the Milky Way would be the size of

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a postage stamp.

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Here's something else to ponder.

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When astronomers look at the most distant galaxies, they're seeing them as they were

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billions of years ago, not long after the Big Bang.

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One of the most humbling images in astronomy is the Hubble Deep Field.

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In 1995, the Hubble Space Telescope pointed at a tiny, seemingly empty patch of sky, about

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the size of a grain of sand held at arm's length.

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What it revealed was astonishing—thousands of galaxies, each containing billions of stars.

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And that's in just one tiny corner of the sky.

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But even with modern tools like Hubble and the James Webb Space Telescope, the true scale

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of the universe is almost beyond comprehension.

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And that's part of what makes astronomy so awe-inspiring.

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The fact that we can observe, measure, and even begin to understand the scale of the universe

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is a testament to human curiosity and ingenuity.

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And it helps connect us in a very real way to the rest of the cosmos.

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If you found this episode useful, let me know and feel free to send in your questions and

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observations.

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The easiest way to do that is by visiting our website, startrails.show.

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This is also a great way to share the show with friends.

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Until next time, keep looking up and exploring the night sky.

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Clear skies, everyone.