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How Many Planets Are in the Solar System?

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In this short explainer video, Universe Today publisher Fraser Cain explains just how many planets there are in the Solar System. How did we go from 9 to 8, and what does this mean for Pluto? http://www.universetoday.com/15568/how-many-planets-are-in-the-solar-system/ --------------- How Many Planets are in the Solar System? I'm just going to warn you, this is a controversial topic. Some people get pretty grumpy when you ask: how many planets are in the Solar System? Is it eight, ten, or more? I promise you this, though, we're never going back to nine planets... ever. When many of us grew up, there were nine planets in the Solar System. It was like a fixed point in our brains. As kids, memorizing this list was an early right of passage of nerd pride: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto. But then in two-thousand-five, Mike Brown discovered Eris, an icy object thought to be about the same size as Pluto, out beyond its orbit. That would bring the total number of planets to ten. Right? There's no turning back, textbooks would need to be changed. In order to settle the dispute, the International Astronomical Union met in two-thousand-six, and argued for, and against Pluto's planethood. Some astronomers advocated widening the number of planets to twelve, including Pluto, its moon Charon, the Asteroid Ceres, and the newly discovered Eris. In the end, they changed the definition of what makes a planet, and sadly, Pluto doesn't make the cut: Here are the new requirements of planethood status: 1. A planet has to orbit the Sun. Okay fine, Pluto does that. 2. A planet needs enough gravity to pull itself into a sphere. Okay, spherical. Pluto's fine there too. 3. A planet needs to have cleared out its orbit of other objects. Uh oh, Pluto hasn't done that. For example, planet Earth accounts for a million times the rest of the material in its orbit, while Pluto is just a fraction of the icy objects in its realm. The final decision was to demote Pluto from planet to dwarf planet. But don't despair, Pluto is in good company. There's Ceres, the first asteroid ever discovered, and the smallest of the dwarf planets. The surface of Ceres is made of ice and rock, and it might even have a liquid ocean under its surface. NASA's Dawn mission is flying there right now to give us close up pictures for the first time. Haumea, named after the Hawaiian goddess of fertility, is about a third the mass of Pluto, and has just enough gravity to pull itself into an ellipsoid, or egg shape. Even though it's smaller, it's got moons of its own. Makemake, a much larger Kuiper belt object, has a diameter about two-thirds the size of Pluto. It was discovered in two-thousand-five by Mike Brown and his team. So far, Makemake doesn't seem to have any moons. Eris is the most massive known dwarf planet, and the one that helped turn our definition of a planet upside-down. It's twenty-seven-percent more massive than Pluto and the ninth most massive body that orbits the Sun. It even has a moon: Dysnomia. And of course, Pluto. The founding member of the dwarf family. Want an easy way to remember the eight planets, in order? Just remember this mnemonic: my very excellent mother just served us noodles. For all you currently writing angry tweets to Mike Brown, hold on a sec. Changing Pluto's categorization is an important step that really needed to happen. The more we discover about our Universe, the more we realize just how strange and wonderful it is. When Pluto was discovered eighty years ago, we never could have expected the variety of objects in the Solar System. Categorizing Pluto as a dwarf planet helps us better describe our celestial home. So, our Solar System now has eight planets, and five dwarf planets. Thanks for watching!
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How many planets do you think are in the solar system? Get ready to have your misconceptions created in this Horizon special 'Bye Bye Planet Pluto'.
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An Infographic trip through the wonders of the solar system. The solar system - well known from countless documentaries. 3D animation on black background. This infographic videos tries something different. Animated infographics and a focus on minimalistic design puts the information up front. We take the viewer on a trip through the solar system, visiting planets, asteroids and the sun. Short videos, explaining things. For example Evolution, the Universe, the Stock Market or controversial topics like Fracking. Because we love science. We would love to interact more with you, our viewers to figure out what topics you want to see. If you have a suggestion for future videos or feedback, drop us a line! :) We're a bunch of Information designers from munich, visit us on facebook or behance to say hi! https://www.facebook.com/Kurzgesagt https://www.behance.net/kurzgesagt The Solar System -- our home in space Help us caption & translate this video! http://amara.org/v/Cr2L/
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It’s long been theorized that there is a planet in our solar system that is beyond Neptune and Pluto. Amy is here to discuss new evidence that might back up this theory. Follow Amy on Twitter: https://twitter.com/astVintageSpace Read More: New Dwarf Planet Found at Solar System’s Edge, Hints at Possible Faraway ‘Planet X’ http://www.space.com/25218-dwarf-planet-discovery-solar-system-edge.html “Astronomers have found a new dwarf planet far beyond Pluto's orbit, suggesting that this distant realm contains millions of undiscovered objects — including, perhaps, a world larger than Earth.” A distant planet may lurk far beyond Neptune https://www.sciencenews.org/article/distant-planet-may-lurk-far-beyond-neptune “If Planet X exists, it may be anywhere from 250 to 1,000 times as far from the sun as Earth.” ____________________ DNews is dedicated to satisfying your curiosity and to bringing you mind-bending stories & perspectives you won't find anywhere else! New videos twice daily. Watch More DNews on TestTube http://testtube.com/dnews Subscribe now! http://www.youtube.com/subscription_center?add_user=dnewschannel DNews on Twitter http://twitter.com/dnews Trace Dominguez on Twitter https://twitter.com/tracedominguez Tara Long on Twitter https://twitter.com/TaraLongest DNews on Facebook https://facebook.com/DiscoveryNews DNews on Google+ http://gplus.to/dnews Discovery News http://discoverynews.com Download the TestTube App: http://testu.be/1ndmmMq
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Astronomers have a massive breakthrough as they discover a weird and very bright extraordinary object in the far reaches of our solar system. Is it a planet? Is it a block of ice? Whatever it is, it's bigger than Pluto. Fascinating science video from BBC Horizon show 'Bye Bye Planet Pluto.'
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Pluto has five moons? Well, yeah! Learn about them in this video. Moon May! One video about cool moon stuff every Mo(o)nday in May. Next(and last): Neptunes Moon Triton. Videos, explaining things. Like evolution, time, space, global energy or our existence in this strange universe. We are a team of designers, journalists and musicians who want to make science look beautiful. Because it is beautiful. Visit us and say hi! http://www.patreon.com/Kurzgesagt https://twitter.com/Kurz_Gesagt https://www.facebook.com/Kurzgesagt http://kurzgesagt.org https://www.behance.net/kurzgesagt THANKS A LOT TO OUR PATRONS FOR SUPPORTING US! The Moons of Mars explained -- Phobos & Deimos Pluto's Five Moons Explained
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The true scale of our cosmic neighborhood. Whoa. Click here to SUBSCRIBE, it's FREE! -- http://bit.ly/iotbs_sub ↓ More below ↓ I took a trip to one of Austin's famous moontowers so I could put the enormity of our solar system into perspective. With the help of a grapefruit, and a lot of walking, you'll get an idea of just how tiny everything is out there!! Do it yourself! Calculate sizes and distances, and then make your own solar system model using this calculator: http://dft.ba/-solarsystem Veritasium "How Far Away Is The Moon?" http://youtu.be/Bz9D6xba9Og Solar system as a football field: http://dft.ba/-6qnn How far away is Voyager right now? http://voyager.jpl.nasa.gov/ ----------------- Have an idea for an episode or an amazing science question you want answered? Leave a comment below! Tweet at me: @jtotheizzoe Email me: itsokaytobesmart [at] gmail [dot] com Facebook: http://www.facebook.com/itsokaytobesmart For more awesome science, check out: http://www.itsokaytobesmart.com Written and hosted by Joe Hanson Produced by Painted On Productions (http://www.paintedon.com/) ----------- Want some more great science? Check out my last episode: Rainbows http://www.youtube.com/watch?v=5pYnC-ONdXQ Want more? Watch: Pay Attention! http://www.youtube.com/watch?v=6-PvAZq3jW4 Want even MORE? "What Is Wind?" http://www.youtube.com/watch?v=xCLwbqmacck "Why Music Moves Us" http://www.youtube.com/watch?v=nT3O93-nxDc