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30

The same reason (almost) all of them rotate in the same direction: because of the conservation of angular momentum. Before a star and its planets exist, there’s just a cloud of disorganized gas and small molecules. The Solar System formed from such a cloud around 4.6 billion years ago. On that scale, there is some small amount of rotation within the cloud....


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In any system of orbiting bodies, the length of time two bodies spend in proximity determines the mutual gravitational perturbation of each body on the other. If both bodies are orbiting in the same direction, the inner body (closer to the central mass [primary star, for instance]) will overtake the outer one, because it is orbiting at a faster angular ...


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It's not true; this object is not a moon of Earth's. Here's a NASA/JPL announcement of it. 2016 HO3 is the "name" being used for it at the moment. They're calling it a "quasi-moon". It's in an orbit that is in resonance with Earth's but is not permanently bound. (It's not the first object to be found with such properties too.)


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The mindboggling GAIA spacecraft-telscope sort of does what you suggest! That's kind of the closest concept to what you describe. Just as explained in JamesS answer, if you were that far away you wouldn't be in orbit around the Earth. But, GAIA's L2-like orbit is kind of the closest thing to what you say. Explanation: https://en.wikipedia.org/wiki/Gaia_(...


3

Its a nice idea, but it wouldn't work. To stay in the Earth's shadow a telescope would need to orbit the Earth in the same time the earth orbited the Sun so that it always stayed on the opposite side. For its orbit to be this long it would need to be a long way out, remember geosynchronous orbit (one orbit in 23h 56min 4sec) is at a distance of 42,164 km. ...


3

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 ...


2

Well, I can't do the math, but if an intuitive answer is OK: If a planet is tidally-locked, can it have an obliquity? I'm going to cheat and give you an answer using moons, because many moons are are tidally locked to their planets. Io is a funny one, it's slightly eccentric orbit and proximity to Jupiter causes it to resurface pretty regularly. ...


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2016 HO3 does not really orbit Earth. It orbits the Sun in such a way that it happens to loop around Earth at distances of 0.1 to 0.25 AU. Earth's gravitational sphere of influence is much smaller, about 0.01 AU at most; outside that radius, the Sun is the dominant attractor. The Minor Planet Center has an orbital diagram which you can examine in 3D. Earth'...


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A distribution is a function mapping from one (or more) variables onto other (often a single, usually non-negative) variable(s). Generally, matter distribution is the relationship between location and mass density (sometimes averages over macroscopic distances, sometimes objects which are assumed to be point masses). Typically in astronomy the radial ...


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A well-known analytical planetary theory is VSOP. The paper describes six versions, most of which are heliocentric. One of them (E) is barycentric and has an extra (ninth) body: the Sun. Hence, for VSOP you have the choice of using the Solar System's barycentre as the origin and computing the position of an extra body, or of computing heliocentric ...



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