When I was a child, there were nine planets.
Now we know thousands of people! But that includes exoplanetsAlien world with alienians. There are only eight planets called our Solar System Home. Or nine could still be measured by some astronomers if they are not yet known not to know Neptune in the past. On the other hand, if you are nostalgic (and an antiestitablashablablilabliestabliestable) there are still nine now, but then you should be fair, in which the sun can only be orbidden by thousands of sunshine.
The planets are a mess. Or maybe more points, it’s a way of thinking about them.
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“What is the planet?” I find a simple question, anything is.
You can go to the old meaning of the word. Planet In ancient Greece means “walkers”, like the planet and the earth as the sun orbit, these heavenly light points seems to move to the background stars. Then that meaning, therefore, would also include the sun and the moon, that most people would agree that the planets would not agree. It would also include kites and asteroids, and for now you can see that it can be too broad.
Maybe it’s more modern. But that also has problems.
The term “planet” was incredibly debatable in the early 2000s. Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Nepikeria and Pluto were claimed that Moniker. But then the hard astronomers had to shake things and shake things by finding Sedna, Quaoar and Er. These are the ice and rock bodies in orbit, Neptune and Pluto in the past, and are large, more than 1,000 miles wide. In fact, it has a width of more than 2,300 km, the madness gives pluto rivals in size and is slightly more massive. Are these planets, then?
When the existence of the EIS was reported in 2005, one of his finds, one of the astronomers Mike Brownalthough He called him “Hament Planet” Along with NASA press materials. At the time it was believed to be a little bigger than Pluto and I was called Pluto planet, and then the planet was worth it. Even better observations had to go down to the sub-plutio, the problem was maintained. How many planets are there in solar system?
The growing mixture caused an international astronomical union, or a global group of IAU-astronomers This is the official cosmic caregiver of the cosmic nomenclature– Creating the Committee of Committee to propose potential definitions of the word. Several proposals were presented, most of which were not at all or another. Among them, for example, the proposal that would enter Ceres was the largest asteroid asteroid between Mars and Jupiter, as the planet. Most people are smaller than what would think as a planet; Many of the planet scientists think they are now ceres protoplanetAt the beginning of the solar system the large object reached almost during the planet period, but the material for growing was exhausted.
Finally, in 2006, Located in the definition of three parts: A planet orbiting the sun, it is massive enough to form a round shape through gravity and “Clearing the neighborhood around its orbit, which means that the body is recorded and prevailed. (Initially the period has caused the confusion, because the planet completely cleans the orbit, it is impossible.) If a body meets the first two requirements, but not the third called “Nano” planet.
This means that Pluto is not considered a major planet like Mercury or Earth, but a dwarf planet. Some astronomers did not like it for the reduced state of Pluto, and certainly today, many public members do not disappear a much voice.
Other definitions have been proposed in the years, better than others. One, in my opinion, It is determined back to Pluto. However, speaking, the reverse engineering is how we reached the division state of the eight planet today. If you mean that it is a planet Pluto, then you should also enter Er, and once set this particular background will be necessary many from other dwarf planets. Without the size or lower mass limit, we must say that the solar system has hundreds of planets, perhaps thousands. Objects must be at least 400 km or more.
Now, we don’t have scientific reasons even Thousands of planets had a solar system, but cultural considerations are other subjects. The planet is excessive that the term will dilute the same, so most space scientists remain strong at eight or nine.
Or is that “nine or 10”? Astronomers follow this idea right now. Many smaller external solar systems appear to have lined orbits aligned in mysterious ways; The easiest explanation is to influence their movements in a large body of unseen That’s often more than 30 billion km of land and orbits from the sun. The temporary (and tongue canvas) is called nine planets, the potential location of the world in the sky is not clear. Different astronomers suggest different hiding places on the nine plans. The arrival of great survey telescopes, such as Vera Rubin Observatory This search is significantly or set to find the planet. If you need to find it, if you want to call it the ninth or 10,000 or 1,000th planet is up to you.
But take care before you complete yourself. I would argue that the main reason we have made to achieve the definition of “planet” is that It’s not the exact thing. He put it as a brown in his 2010 Book How did I kill Pluto and why he came, It is a concept of “planet”, generalizing than the definition. He is right. There is no hard and fast line to define and distinguish between other classes of objects that we can draw around the concept of a planet. Whether mass, size, shape, orbit or apparently decide whether any other property is decided, the criteria of the planet are inevitably arbitrary.
Such sliding is a universal issue in natural sciences: definitions are a human invention, it is not a natural event. Look at the colors; We define the long-wave cutting for everything red versus red, but that limit was an option, not something observed. Blue light and red light There are two flavors of the same thing, with different wavelengths. And all colors are literally in a spectrum; Bat is well blended next time without a sharp step.
It’s not hard to get more examples: sex, gender, political affiliation, species and more. All of these are on the spectrum. The differences are evident at the opposite ends of a spectrum, temptation to put into a binary category, but when you compare the two samples associated with that spectrum, many differences are more difficult. So where do you draw the line?
Humans like to put things in light-cut categories, but it is generally not so elected. Life can be much easier and help us to understand the universe and ourselves better.
