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Is Pluto a planet?

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04:45
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  • 1 1:32

    Pluto is smaller than 9 moons in the Milky Way galaxy.

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  • 2 2:55

    Pluto was discovered in 1930.

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  • 3 3:33

    Pluto was re-categorized as an object in the Kuiper Belt, alongside other icy orbs.

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03:57
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Pluto's not a planet. We're sorry, but we think it's time you move on. If you've gone through all your breakup music and Meg Ryan movies, and you still can't get over it, then SciShow Space will get out the ice cream, cuddle up with you on the couch, and talk about how this could have happened. ---------- Like SciShow? Want to help support us, and also get things to put on your walls, cover your torso and hold your liquids? Check out our awesome products over at DFTBA Records: http://dftba.com/artist/52/SciShow Or help support us by subscribing to our page on Subbable: https://subbable.com/scishow ---------- Looking for SciShow elsewhere on the internet? Facebook: http://www.facebook.com/scishow Twitter: http://www.twitter.com/scishow Tumblr: http://scishow.tumblr.com Thanks Tank Tumblr: http://thankstank.tumblr.com Sources: http://www.universetoday.com/13573/why-pluto-is-no-longer-a-planet/ http://www.universetoday.com/32515/kuiper-belt/ https://solarsystem.nasa.gov/planets/profile.cfm?Object=Dwarf&Display=Sats http://www.nasa.gov/mission_pages/newhorizons/main/#.UyXHgvmSxNs
07:54
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What is a planet? The question has been pondered by many since the early Greeks came up with the word "planets." Since then the number of "planets" in our solar system has fluctuated, sometimes numbering as high as 15, before it was determined that some were actually asteroids. One such celestial object is Pluto, which became the 9th planet in 1930 to much controversy. Then, in 2005, Eris was discovered and hailed as a possible 10th planet. Our technology has progressed to the point where we are able to see farther into space than ever before. In so doing we have discovered a section in our solar system called the Kuiper Belt that has the potential to hold hundreds, if not thousands, of objects similar to Pluto and Eris. Much like other sciences, such as Biology, where one may discover a new species, classification is a common and needed process which groups like objects for purposes of comparison and further study. The classification of our planets is no exception to this scientific practice, and the astronomical community is currently undergoing a discussion debating the issue of how to classify, or define, a planet. Using 3D animation, this DVD was created to better illustrate the history behind the discussion defining "What is a Planet?" and to outline some of the traits that may be associated with the definition of a planet. So come travel with us as we drive along the "Kuiper Belt highway" at 100 mph to explore the far reaches of our solar system and discover how vast our corner of the galaxy really is.
02:05
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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
04:54
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This is a video explainer that describes why Pluto is no longer a planet. It talks about the history of Pluto and its discovery, and then the discovery of Eris, which is larger than Pluto. Now you can learn the official rules for planethood. Created by Christian Ready for Universe Today
03:53
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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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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!