字幕列表 影片播放 列印英文字幕 What do you think killed the dinosaurs? A comet? A volcano? What about Dark matter? Hey guys Julia here for DNews Over 65.5 million years ago a comet slammed into earth sending a giant death plume of debris into the atmosphere, killing almost all life on Earth including most of the dinosaurs. We’ve figured this one out, we’ve got the evidence. A huge crater in the middle of Mexico’s Yucatán Peninsula. But what sent that comet hurtling to Earth in the first place? Well some geophysicists like Michael Rampino, from New York University noticed something strange in the fossil record. They found that every 30 million years or so, there seemed to be a mass extinction. Some of these were smaller extinctions, but most of the big 5 mass extinctions match up with this timeline. So what could be working like clockwork to trigger a great loss of life on this planet? Well some scientists like Rampino have an idea. They point the finger at dark matter. Yup that strange mass of something out there that we can’t see but only detect through its gravitational effects on objects around it. Some estimates say as much as 85% of all the stuff out there in the universe, is actually dark matter. Theoretical physicist Lisa Randall suggests in her new book "Dark Matter and the Dinosaurs: The Astounding Interconnectedness of the Universe" that dark matter might be responsible for sending comets to Earth. So there might be dark matter concentrating near the center of our galaxy, the Milky Way and forms a kind of thin cloud. Randall suggests that maybe it’s more of a disk made up of particles 100 times larger than a photon. The disk might be thin and dense. As our solar systems moves through the disk, it bobs up and down, like an apple in barrel full of water. And those bobs are pretty regular, about every 30 million years or so. Because the disk is so dense, the gravitational tug would affect planetary bodies in our own solar system. It could even knock comets loose from their orbit in the Oort cloud, a cloud of dust and comets, sending them towards Earth. And maybe this was the case for the rouge body that slammed into Earth 65.5 million years ago. But it’s not just rogue comets this dark matter cloud could trigger. It could trigger volcanoes! That’s what Rampino suggested in an article published in the journal Monthly Notices of the Royal Astronomical Society. He claims that the dark matter particles gather in clumps in the disk. And those clumps get swept up by the Earth as it passes through the disk. These particles collect in the center of the Earth where they reach sufficient densities annihilate each other, producing enormous amounts of heat. This heats up the Earth’s core by a few hundred degrees which expands the molten lava putting pressure on the crust until it erupts in huge volcanic eruptions. Maybe huge enough to wipe out most of life on the planet. Though I should caution these ideas are still speculative at this point. There’s still not a lot of evidence for a disc of dark matter in the center of our galaxy. There’s some evidence that our nearest neighboring galaxy Andromeda might have one. And evidence of our own is yet to come, the European Space Agency’s Gaia missions could reveal more about dark matter. The mission will track the movement of hundreds of thousands of stars throughout the Milky Way, through which we could learn about the distribution of dark matter. Till then, other scientists like Coryn Bailer-Jones, an astrophysicist at the Max Planck Institute for Astronomy told Scientific American that they remain skeptical about such a hypothesis. Some claim that the evidence is scarce for a clumpy dark matter disc, and others like Bailer-Jones even question the periodic nature of mass extinctions. So while it’s a very cool hypothesis, I mean who doesn’t love dark matter, dinosaurs and volcanoes in ONE HYPOTHESIS? I’d say more research is needed. You know what else is really cool together? CLONING AND DINOSAURS! Recently, we discovered actual fossilized dinosaur eggs. Does this mean we're closer to cloning a dinosaur and starting an awesomely terrifying theme park? Check out this video to learn more. Hey Guys, if you like the shirt i have on and want to check out other DNews shirts be sure to go to the link below. We have a ton of cool science shirts for your buying pleasure. AND if you’re a first time buyer use the promo code DNEWS for 10% off at checkout.
B2 中高級 暗物質殺死了恐龍嗎? (Did Dark Matter Kill The Dinosaurs?) 105 14 Serena 發佈於 2021 年 01 月 14 日 更多分享 分享 收藏 回報 影片單字