Pluto is a planet

Thanks for Lexus to challenge me in this exciting debate! I will first write the definitions from Oxford Dictionaries. DefintionsPluto: A small planetary body orbiting the sun, discovered in 1930 by Clyde Tombaugh. Pluto usually orbits beyond Neptune at an average distance of 5,900 million km from the sun, though its orbit is so eccentric that at perihelion it is closer to the sun than Neptune (as in 1979–99). Pluto is smaller than earth’s moon (diameter about 2,250 km), but it has its own large satellite(Charon), and three other small moons. From the time of its discovery it was regarded as the ninth (outermost) planet of the solar system, but in the 1990s its unusual characteristics ledastronomers to question its planetary nature. In August 2006 the International Astronomical Unionformally declared Pluto to be a dwarf planet rather than a planet properPlanet: A celestial body moving in an elliptical orbit round a star. . http://www.oxforddictionaries.com...http://www.oxforddictionaries.com...What happened to Pluto? Pluto was discovered in 1930 by an astronomer from the United States. An astronomer is a person who studies stars and other objects in space. Pluto was known as the smallest planet in the solar system and the ninth planet from the sun. Today, Pluto is called a “dwarf planet. ” A dwarf planet orbits the sun just like other planets, but it is smaller. A dwarf planet is so small it cannot clear other objects out of its path. On average, Pluto is more than 3.6 billion miles (5.8 billion kilometers) away from the sun. That is about 40 times as far from the sun as Earth. Pluto orbits the sun in an oval like a racetrack. Because of its oval orbit, Pluto is sometimes closer to the sun than at other times. At its closest point to the sun Pluto is still billions of miles away. Pluto is in a region called the Kuiper (KY-per) Belt. Thousands of small, icy objects like Pluto are in the Kuiper Belt. Pluto is only 1,400 miles (2,300 kilometers) wide. That's about half the width of the United States. Pluto is slightly smaller than Earth's moon. It takes Pluto 248 years to go around the sun. One day on Pluto is about 6 1/2 days on Earth. Pluto was named by an 11-year-old girl from England. The dwarf planet has five moons. Its largest moon is named Charon (KER-ən). Charon is about half the size of Pluto. Pluto's four other moons are named Kerberos, Styx, Nix and Hydra. Arguments Those who feel that Pluto has always been a planet and jolly well ought to be one again have received a boost - this time from a top NASA boffin, albeit a slightly biased one. "It's very hard not to call an object with this level of complexity in its geology, and such complex seasons, a planet," said Alan Stern, New Horizons' principal investigator at Southwest Research Institute, during a press conference about the probe's latest update. "Astronomers and planetary scientists differ on this question but that's how science works – scientists make individual decisions and consensus is reached. I think we're going through a period of transition at the moment. " Data from the New Horizons space probe has shown Pluto to be geologically active, with new glacier plains of nitrogen ice carving out new surface features and eroding away impact craters from meteor strikes. It has a large, hazy atmosphere extending 100 miles from the surface, and the New Horizons data has revealed a lot about the dwarf planet's history. We heard during the briefing that Pluto is almost perfectly spherical, which was unexpected considering what we think happened during its formation. It's likely that way back in its history, Pluto was hit by a massive object that tore away a huge chunk of its mass, which went on to form into the freezeworld's five moons. But no remnant of that impact can be seen on the surface or in its current clean, spherical form. That means that Pluto must have been spinning very rapidly after the impact, William McKinnon, New Horizons co-investigator at Washington University said, before reaching equilibrium with its relatively massive moon Charon.2. Pluto has many features of planets. It should be a planet f Pluto were a planet, then many of the worlds Brown discovered would also be planets, meaning he would have discovered more solar system planets than any individual in human history. Which would be really cool, he says, “but it would just feel kind of fraudulent. ” The flood of new worlds at the outskirts of our solar system is exactly what led to Pluto’s demotion. There are at least four would-be planets out there in the farthest reaches of the solar system, and more are likely hiding in the crowded Kuiper belt. Scientists still can't entirely agree on what to do with this hodgepodge of small, icy worlds. The New Horizons spacecraft’s flyby of Pluto on July 14 is making the former planet come alive. High-resolution images have put a face on this once-mysterious world. We’ve probed its atmosphere and imaged its moons for the first time. Icy peaks rivaling the Rocky and Appalachian Mountains slice through its lower atmosphere, and nitrogen glaciers have carved up its surface sometime in recent geological history. “What else would you call it besides a planet? ” says New Horizons mission leader Alan Stern. Pluto's Young, Icy Mountains NASA-JHUAPL-SwRI This view from 478,000 miles shows that Pluto is home to huge, 11,000-foot tall mountains, probably composed of water ice. The lack of impact craters suggests that Pluto's surface is young, probably less than 100 million years old. Defying the International Astronomical Union (IAU), which names objects in space and redefined Pluto’s status in 2006, Stern and his colleagues have been calling Pluto a planet during NASA’s televised events. This Pluto pandering does a disservice to the public, says Brown. “As an educator, I would like people to understand what our real solar system is like, not a cartoon of it. Calling Pluto a planet is like a cartoon solar system all over again. ” If this feels like déjà vu, it’s because the Pluto flyby has predictably revived a bitter debate about how best to define a planet. 3. Size doesn't matter Some planetary scientists, such as New Horizons’ Alan Stern and the Dawn mission’s Mark Sykes, aren’t buying the “size matters” argument. They think that any object that orbits the sun and has enough gravity to pull itself into a spherical shape should be called a planet. “When they get that size, that’s when geology turns on,” Sykes told Popular Science during an interview in January. Scientists on this side of the debate don’t like the IAU’s definition since it depends on a world’s neighborhood instead of its intrinsic properties. If Earth were placed in Pluto’s position, it wouldn’t clear its orbit either, says Stern. And although Earth’s diameter is five times larger than Pluto’s and that may seem like a big difference, Saturn and Jupiter are 9.5 and 11 times the size of Earth, respectively. Going off of just size alone, the line that separates real planets from minor planets could easily be drawn to exclude Earth. From left to right: Mercury, Venus, Earth, Moon, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto, Haumea, Makemake, and Eris. The IAU’s definition is also only applicable to our solar system. For the planets that orbit other suns, the IAU will come out with a separate definition—an interesting choice for an organization whose goal is to standardize conventions and ensure consistency. Scientists now estimate that there are billions of these exo-worlds in our galaxy--that planets are not nearly as special as we once thought. Maybe it's time to extend that philosophy to our own solar system.