字幕表 動画を再生する 英語字幕をプリント Hey, Vsauce. Michael here. And the year 6009 will be the very first year since 1961 that a year when written in Hindu-Arabic numerals can be inverted and still look the same. But you and I probably won't live long enough to enjoy the year six thousand and nine. Human lives just aren't long enough. We will miss out on that. What other cool future offense will we be missing? Well, first of all, you and I will probably be gone before the completion of the time pyramid in Wemding, Germany. It will eventually be a pile of 120 concrete blocks. But the builders are only adding one block every 10 years. Since beginning in 1993 they've added only the first three. At this rate the pyramid will be completed in the year 3183. The final block placed by our great great great great great great, more than 30 greats grandchildren. But even they will miss an opportunity to frolic and play safely in the Chernobyl Exclusion Zone. The zone of alienation, where radioactive contamination from the 1986 disaster will remain at levels too high for safe human activity until not the year 4000, not the 5000, not the 6000. It will finally be safe probably in the year 22 000. Possibly within our lifetimes but definitely within the next one million years, stars like Betelgeuse and Eta Carinae will explode in brilliant supernovas visible from earth. I'm bummed I'm probably going to miss out on these events because for a few weeks it will look almost as if earth has two Suns. Despite being hundreds, thousands of light-years away, their supernovas will shine brighter than the full Moon at night and be visible even during daytime. But the real sky show comes in 3.75 billion years. Our galaxy is full of stars, viewed from the surface of the earth they look like little drops of milk in the sky, which is why we call it the Milky Way Galaxy. But all galaxies are named after milk. Milk, lactose, lactic, ga-lactic, galaxies. And every drop of milk in the sky, every star that you can see, is inside our galaxy, the Milky Way. But there's a blurry distant shape. This one. It's not a star, it's not a cloud of gas in our galaxy, it is an entirely different Galaxy - the Andromeda Galaxy and it's two-and-a-half million light years away from our own. It contains twice as many stars as the Milky Way and it is coming our way. Headed toward us at 300 kilometres a second, faster than a bullet. Right now, the sky looks like this. In 2 billion years Andromeda will have approached so closely that people will look up at the sky and see this. In 3.75 billion years the night sky will be like a scene from a science fiction movie or an awesome desktop wallpaper. Incredible and kind of scary. After this scene, the sky will literally be glowing with the birth of new stars as the Milky Way and Andromeda collide, mixing up into a brilliant cosmic tie-dye. This simulation shows how Andromeda might collide with the Milky Way, but keep in mind that you are watching billions of years pass every second. These galaxies are moving fast but they're also huge and covering even huger distances. They will collide in the future but within the briefness of a single human life they appear almost frozen, unmoving. A couple billion years after colliding the course of both galaxies will be married together in a bright glowing centre. Earth, now a stepchild to what was once Andromeda, part of a new, bigger family called Milkdromeda. It would be so cool to be alive to see our galaxy colliding with another. But don't get all fomo, consumed by a fear of missing out. Because whatever life is around then will have plenty to envy us for. They may have spectacular nightly views, but secretly wish they'd been born in our time to experience, say, the beginning of the Internet. They will actually miss out on a lot of things. Because the Moon moves one centimetre further away from earth every year, 600 million years from today the Moon will no longer be close enough to earth to completely block out the Sun. Future humans or descendants of humans will therefore miss out on a chance to ever see for themselves the beauty of the total solar eclipse from the surface of Earth. Long before earth dries up Niagara Falls will dry up. Well, not the water part, but the falls part. Every year the rushing water of Niagara erodes the rock at the top of the falls one foot backward. By the year 52 000 it will have eroded all the way to Lake Erie and our progeny will have no Niagara Falls to enjoy. Granite has an erosion rate of about one inch per ten thousand years. So, certainly by the year 7 million Mount Rushmore, especially its faces, will no longer exist. And because they slowly get pulled in or rejected into space, in 50 to 100 million years Saturn will no longer have its lovely rings. So, life on earth in the future might have awesome supernovas and galactic collisions to look forward to but they probably won't have Niagara Falls, Mount Rushmore, total solar eclipses or Saturn's rings. They also won't have you. But you have you. Except not all of it. Babies don't begin to form episodic memories right away, meaning that you missed out on. You don't remember two of the most seminal events in your life. Your conception and your birth. But you can experience a bit of those moments right now. First of all, When Was I Conceived? dot com lets you enter your birthday and get back the week your parents probably made you happen, as well as the number one song and the number one movie of that week, which may have also been involved. Light travels quickly, the most quickest in fact. But it can take a photon millions of years to escape from the interior of the star it was created in through nuclear fusion. It takes time, just like your own gestation in your mother's womb. Newly conceived photons struggle through a dense stellar jungle of atoms and molecules and electrons that absorb and reemit the photon, taking a little bit of energy from it as a randomly rolls around like a pinball. Sometimes after thousands or millions of years it's random walk finally leads it to the stars' surface, where it pops out into space. In a way, is born. A lucky, tiny tiny tiny percentage of the photons that reach the surface of a star find themselves on a path that will intersect with earth. And if you are lucky, those photons will end their journey by being absorbed under your own retina. If you enter the date of your birth or the approximate date of your conception into this online calculator you can find a star that is as many light years away from earth as you are old. When you look up at that start today, you are seeing light that left the star the very month you were born or photons that left that star and entered space when your entire body was just one cell. Space is really big and your life is very short but space is so gosh darn big you don't have to miss out on everything. And as always, thanks for watching.