Here is a simple question: What is the moon?
As so many questions in science, it may seem Correct but really not. “Why, the moon is a planet orbititen a heavenly body,” I surely think. Well, for sure – if you bend your eyes and if you don’t get very close, it’s a pretty decent description.
But the term “Moon” is not so easy to define.
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The canonical example, of course, is our moon, rough piece of stone that he orbit the earth. But a few centuries the first telescopic remarks of other planets revealed that many have seen the moon; Jupiter has four giants, easily observed satellites, and Saturn also means humble means. Then, during that time, the definition of “moon” seemed safe enough.
Then, of course, things were complicated because they always do it. As the telescopes were growing, more moon were found. Mart has two and the poor mercury does not at all, but in contrast, apparently, it seems like a mushroom after a reson. In the first half of the twentieth century, Jupiter learned that he had a dozen. More handfuls were found telescopically in the 1970s, and the numbers jumped slightly when we started sending space ships to external plants. Then in the 2000s, numbers denounce More specific ascending techniques were used to study Jupiter’s environments.
As a result of this writing, Jupiter confirmed 95 monsons. They have size from the most powerful ganymede, the largest solar system in more than 5,200 kilometers than Planet Mercury. Saturn is farther than Jupiter, so his moons are more difficult, but now we know at least 274 moon, an amazing number! Of these, 128 This month were announced used by scientists Advanced search technique This allows very weak satellites in telescopic observations. Most of these new increments are a few kilometers.
It is clear that ever stronger equipment, we will find that many planets have small dimensions of orbital measures. Is it something the size of a football stadium moon? Sure! But what about a car size, basketball or grape? What about a grain of dust?
Saturn’s rings are made up of billions of small ice cream particles. Is each of these moon?
In a lower limit, this term does not appear to be adapted.
The problem is even more complicated Many asteroids have moon. Asteroids are known more than 430 or orbiting smaller asteroids. It is likely that these satellites formed low-speed collisions, which were flipped materials that were considered materials or slowed enough asteroids to put each other in orbit around each other. In some cases an asteroid and its moons have also been formed together.
The past Neptune’s past freezing and small rocks are Trans-Neptunia (TNO), and many of them also have. While some nano planets can be called nano, they are much small and Don’t fall near to this category.
And even though I hate things even more difficult, I need to consider if we expand our definition of the moon “Any object that orbiting something larger”, then The planets are the moon. Small stars would also be the little stars in the stars!
We are clearly talking to try to hang the word moon in these objects.
There is also a problem Arguments about what makes the moon can change in a different way. For example, the tug of the gravity of the sun are harder on the moon than the earth! So is the moon orbiting sun or our planet? Well, here’s the trick, both the earth and the moon sun orbit together. The influence of the sun is equal to both, so it is canceled in a sense, so the moon orbiting our planet orbit over the sun orbiting the sun.
There is mathematical support for this. Balancing the equations of the gravity of a planet and a star, including the centrifugal force created by the body, extends the “influence of the planet”. This area is also called the gravity of the planet in the place where it dominates hill sphereGeorge Hill after American astronomer, derived from the first time. The hill sphere for the ground, seen from the sun distance, is about 1.5 million km. The moon is about 385,000 km from the ground, so it is in the field of our hill and therefore under the influence of the earth than the sun.
This space region grows farther and farther is the star planet. Jupiter is more massive than Saturn, but Saturn is farther away from the sun, so his core sphere is the volume of Jupiter almost twice. Therefore, why have we found so many moon orbiting Saturns, despite being farther away from the ground, so it’s harder to look for friends.
Neptune is far from the sun, his cord sphere is the largest among all the planets. It is likely that Neptune have much more moon than Jupiter or Saturn, and we have not yet found it because they are still too weak to see easily from the ground.
This still leaves us some interesting edges. Pluton has five well-known monsons. The largest, Charon, was found in 1978. Pluto is half of the diameter and is eighth mass. Therefore, Charon does not have so many Orbit Pluto, both in orbit, mass center. Sesaw is like two people; The balance point is closer to the person who weighs more. Pluton-Charon Barycenter Pluto is out of the body itself! Is Charon moon? Or is it more that both form a binary planet?
More difficult, It is possible to have the moon! Similar to the mountain sphere argument for the planets, some peace can have their own impact on their own. What do we call them? Some discuss the term “Moonmoon”, determining a wonderful but somewhat. I prefer “Summon”.
Don’t start me in quasi-paste.
Eventually, the problem is in the priority of direct simplicity than the complex nuance; Dealing with a sharp term “Moon” is not definable. A is a concept More than definition, It’s like the term “Planet”. Maybe that’s why International Astronomical UnionCelestial Name and Definition Career has no definition of what makes the moon.
Humans like things to put things in separate bins, but nature is not so prejudice. When the objects fall in a district, the feature spectra, the transition of this spectrum is usually smooth and trying to cross the specified limits more exceptions than regulatory followers.
Sometimes it is best to accept something about how it is and not in our tight classifications. You can understand that way, and isn’t that?
