# What time is it on Voyager 1? 🤔

## Метаданные

- **Канал:** Be Smart
- **YouTube:** https://www.youtube.com/watch?v=UI8pp2j2fZ8
- **Источник:** https://ekstraktznaniy.ru/video/32470

## Транскрипт

### Segment 1 (00:00 - 02:00) []

- What's the farthest manmade object from Earth? It's a space probe called Voyager 1 launched by NASA in 1977. It's zooming away at 17 kilometers per second and is now more than 25 billion kilometers away. But what's weird is that the clock on Voyager 1 reads a different time than ours. That's thanks to something our friend Albert Einstein figured out. His theory of special relativity showed that time passes slower for clocks when they're moving. It sounds crazy, but scientists have demonstrated this effect over and over. We actually have to account for how time passes differently on GPS satellites orbiting the Earth in order to track our location accurately. Okay, so Voyager 1's been traveling for a little over 48 years at around 17 kilometers per second. According to Einstein's equations for special relativity, Voyager's clock has lost about two and a half seconds since it launched, but Einstein gave us another mind bending lesson to consider, his theory of general relativity. In addition to time being stretched for moving objects, time is also warped by gravity. When you're close to a massive object like a planet or a black hole, your clock will tick a tiny bit slower than if you're far away from it. Our GPS satellites have to account for this effect too. And since Voyager 1 is now more than 25 billion kilometers from Earth, it obviously feels the gravitational pull of our planet much less than we do. That difference from Earth's gravity means Voyager's clock will actually tick about a second faster than an Earth clock. And if you combine both of these time dilation effects, Voyager's clock should be about a second and a half behind ours. But it gets even weirder because Earth is moving really fast too. In fact, the Earth's velocity around the sun is even faster than Voyager zooming through space. Plus, we're much closer to the giant heavy sun than Voyager is. So our clock is slowed even further by its gravity. If you do all these calculations relative to a point at the center of our solar system, factoring in the speed of Voyager, the differences in gravity and the speed of spaceship Earth, the clock on Voyager is actually somewhere around 20 seconds ahead of ours on Earth. Woo. So what time is it really on Voyager 1? Well, it could be the future or the past. Just depends on where you sit. Follow me for more cool science videos.