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8

The various moons are on orbits that are mostly a lot more than 1km apart from other moons. The orbits are stable, so the moons just keep going round Saturn on the same orbit. The moons are far enough apart that they have negligible gravitational influence on other moons. So the moons never get close to each other and don't collide. There are moons, like ...


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First, Pluto isn't a planet, and hasn't been for about a decade. It's a dwarf planet, and is better grouped with other small, rocky objects beyond Neptune's orbit, such as Haumea. These objects, and other minor planets, have more in common with objects in the Kuiper Belt and Oort Cloud than the eight planets of the Solar System.1 Therefore, we see a ...


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Stars are much less bright than the earth in full sunlight as per your picture. So with the exposure required to give that picture of earth, no, you won't see stars. But move the camera a bit to the side, so earth is not in shot and you can see stars. The same goes for the sun - make sure sunlight is not entering the lens, and you can easily see stars. ...


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Sir Cumference's answer is great. Molecular clouds are generally thousands of times more massive than the Solar System, and since they're less dense they're much much larger in volume. We don't know where our Solar System originated from, and we don't know how many other stars were born in the same cloud, probably hundreds or even thousands (just recently 1 ...


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Indeed, the situation is temporary on a scale of hundreds of millions of years, with reoccuring instabilities. The moons don't run into each other in the short term, but the orbits affect each other and are affected by The sun and other bodies in the solar system. See this presentation by Matija Cuk for details. Recently the age of Saturn's moons ...


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If you are calculating the angular distance between planets, as viewed from Earth, then of course you need to include the retrograde motion. The natural way of doing this would be to first use heliocentric coordinates to calculate the positions of both planets and the Earth relative to the sun (You could do this using Kepler's laws). Then change your ...


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In our moving Earth-based point of view, retrograde apparent motion means a planet's geocentric ecliptic longitude is temporarily decreasing instead of increasing as usual. The word "apparent" avoids confusion with a retrograde orbit. All major planets' orbits are prograde, with heliocentric longitude increasing at all times1. Most retrograde-orbiting Solar ...


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If I understand you correctly, you ask why does the length of the day not change much around the winter solstice. There is no mystery here: The rate of change of day length has (almost) nothing to do with the elliptical orbit of the Earth. In autumn the days get shorter; the rate of change of day length is negative. In spring the days get longer; the rate ...


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The next aphelion is July 4 at UT 16:24. Next perihelion Jan 4, 2017. Depending on latitude, the length of daylight varies over a year. Since the Earth's spin is NOT locked to its rotation, where the Sun is in the sky on the same date for consecutive years will not be the same. I am unable to find a table of day lengths to the second, so I can neither ...



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