All of the planets in our solar system are constantly orbiting around our sun. Each planet has its own unique path and the distance between them is based on the position they are in within their orbit. Each planet also has its own speed of rotation, some head around the sun very fast and some are quite slow. Saturn is the sixth planet and is often called the ‘jewel’ of the solar system because of its beautiful rings. As it moves throughout its rotation, planets do come close to it, but it is most consistently close to Jupiter.
When Saturn and Jupiter are lined up, there is only a distance of 655 million km. That’s fairly close, from a planetary perspective. When Jupiter and Saturn are on opposite sides they are 2.21 billion km apart. During that alignment, all of the other planets are actually closer to Saturn than to Jupiter.
Occasionally, Uranus will get closer to Saturn, at a distance of 1.42 billion km. In the solar scheme of things, distance and how ‘close’ the planets are is completely dependent upon the orbit and speed of each of the planets. Astronomers that study the planets have noted that Jupiter’s orbit is actually at the beginning of the outer portion of the solar system. It takes Jupiter twelve years to complete its orbit around the sun and average of almost 500 million miles. Saturn, on the other hand, is located almost twice as far away from the sun as Jupiter is and it takes Saturn almost thirty years to complete its orbit around the sun.
Here is an easier way to see how this works. Imagine a field and in the center of the field is a post. That post would represent the sun. Now put 8 kids, lined up outwards from the post, with the last child all the way out to the end of the field. Each person will have to go all the way around the post and each child will be going at different speeds: some walking, some jogging and some running. The one closest to the post doesn’t have to go very fast to get all the way around the post. The last child has a longer distance and even if they run, it will take them awhile. As the kids go around the post enough times, there will be moments when all of the kids line up, but as you watch this game you will find that it is rare.
Using the example above, you can see how the speed and distance of Saturn and Jupiter can let them be close in orbit most of the time, but it isn’t always the case. There will be times when Uranus lines up closer to Saturn. This is why it’s difficult to actually give an answer as to the ‘closest’ planet to Saturn.
Due to the way the planets orbit and the various speeds, it is also a rare circumstance when all of the planets ‘line up’. It is usually within thirty degrees of measurement. Astronomers have calculated that the last time it happened was 561 B.C. and the next time will be 2854.
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