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A Hello That Takes a Whole Day! Voyager 1's Giant Space Milestone

2026-11-02 · Watch on YouTube

Summary

What if your hello took a whole day to reach a friend? Follow one little hello from Earth on its 24-hour trip to Voyager 1, the farthest spacecraft ever, as it reaches one light-day away on November 15, 2026.

Transcript

0:00A Very Slow Hello

0:00What if you said hello to a friend, and they didn't hear it until tomorrow? Not because they weren't listening, but because your hello had to travel that far! It sounds impossible, but it's real. Way out in deep space, there's a little spacecraft called Voyager 1. 0:15It's the farthest thing people have ever built and sent away from home. On November 15, 2026, Voyager 1 reaches a spot so far away that a message from Earth takes one whole day to get there. So today, you and I are going to send it a hello and ride along for the trip. 0:34But first, let's meet our faraway friend.

0:37Meet Voyager 1

0:37Voyager 1 blasted off on a rocket way back in 1977. That's so long ago, your grown-ups might not have been born yet! It's about the size of a small car, with a big round dish on the front, like an umbrella flipped inside out. 0:51That dish is its mouth and its ears. It's how Voyager talks to us. Wow fact: on its way out, Voyager 1 zoomed past Jupiter and Saturn and sent back amazing pictures of swirling storms and shiny rings. 1:05Then it just kept going, and going, and going. So how do you say hello to something that far away? Shouting won't work. You need some really, really big ears.

1:15Earth's Giant Ears

1:15Here on Earth, scientists use giant dish antennas to talk to spacecraft. The biggest ones are about 70 meters across. Fifty kids lying head to toe would barely stretch from one side to the other! There are big dishes like these in three places around the world: 1:31California, Spain, and Australia. As Earth spins, at least one of them can always point toward Voyager. Now let's pretend our message is one little word: hello. The dish beams it into space as radio waves. 1:47You can't see radio waves, but they travel at the speed of light, the fastest speed there is. And just how fast is that? Hold on to your seat!

1:56Faster Than Fast

1:56Light is so fast, it could zip around the whole Earth about seven times in just one second. Snap your fingers. Whoosh! That's seven trips around the world already. 2:06So our hello reaches the Moon in just over one second. To go as far as the Sun, it needs about eight minutes. Wow fact: the sunshine warming your face today left the Sun about eight minutes before it touched you. 2:19You're feeling light that's been traveling while you ate your snack! But Voyager is far, far beyond the Sun's distance. So let's start a clock and watch how far our hello can get in a few hours.

2:32Racing Past Planets

2:32Tick, tock. In less than an hour, our hello has already flown farther than Jupiter. By about an hour and a half, it's past Saturn and its rings. After about four hours, it reaches the distance of Neptune, the last big planet, 2:45a blue world far from the Sun's warmth. Wow fact: a jet airplane would need more than five hundred years of nonstop flying just to go as far as Neptune. Our hello did it before lunchtime! 2:57But we're not even close yet. Four hours down, twenty to go. And up ahead, there's an invisible border waiting.

3:06The Sun's Bubble

3:06The Sun is always blowing out a gentle wind of tiny, tiny bits. That wind puffs up a giant bubble around the Sun and all its planets. Scientists call it the heliosphere. In 2012, Voyager 1 became the first spacecraft ever to sail out of that bubble 3:23and into the space between the stars. Around hour seventeen, our hello crosses that border too. Wow fact: Voyager is moving about 17 kilometers every second. That's fast enough to fly all the way around the Earth in less than an hour! 3:40Hour twenty. Hour twenty-two. Hour twenty-three. And then, at last...

3:46One Light-Day Away

3:46Hour twenty-four! Ding! Our hello reaches Voyager 1, one whole day after it left Earth. That distance has a special name: one light-day. 3:56It's how far light travels in one day, almost 26 billion kilometers! But here's the twist. Voyager's answer has to make the very same trip back. So if you say hello on Monday at breakfast, Voyager's 'hi back' won't reach 4:09you until Wednesday at breakfast! And it gets even stranger. Every message we get from Voyager is a day old. When scientists check on it, they're really seeing what Voyager was doing yesterday. 4:22Talking to Voyager is like getting a postcard from yesterday, every single time! So way out there, all on its own, does Voyager carry a hello of its own? It sure does. And it's golden.

4:36The Golden Record

4:36Fixed to the side of Voyager 1 is the Golden Record. It's a shiny gold-covered disc, like an old-fashioned music record, built to last for a very, very long time. It's filled with the sounds of Earth: rain, wind, thunder, birds singing, whales calling, 4:52footsteps, and people laughing. It also has music from all over the world and pictures of our planet. Wow fact: it says hello in 55 different languages! And the English hello is spoken by a young child. 5:07It says: 'Hello from the children of planet Earth.' There are even picture instructions on the cover showing how to play it. So Voyager carries Earth's hello outward, while our hellos chase after it. But where is it all heading?

5:22Sailing to the Stars

5:22Voyager 1 will never turn around. Every second, it sails farther out among the stars. Its power is slowly getting lower, so scientists back home carefully switch off parts it doesn't need anymore. 5:35That way, it can keep talking to us for as long as possible. Wow fact: in about 40,000 years, Voyager 1 will drift a little closer to another star. And the Golden Record will still be on board, carrying Earth's hello. Now, let's bring our own hello back home.

5:52Your Space Track

5:52Voyager 1 left Earth in 1977, and now it's one light-day away, so even a hello moving at the speed of light needs a whole day to get there. And it carries a Golden Record full of Earth's hellos. So remember that friend who wouldn't hear your hello until tomorrow? 6:08That friend is real, and its name is Voyager 1. Here's your challenge for today: build a space-message track with a roll of toilet paper. Ask a grown-up first. 6:18Put the end of the roll at a doorway. That doorway is Earth. Count out one square. That's how far sunlight travels in about eight minutes. 6:27The Moon would be a tiny smidge from the door! Now gently unroll about 170 squares down a hallway, and put a sock at the end. That sock is Voyager 1, one whole light-day away. Walk the track slowly, whispering hello, then roll the paper back up so it's ready to use. 6:45One square for the Sun, about 170 for Voyager, and a sock waiting a whole day for your hello.

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Series: science (English)