Questions regarding the movement of an object at a given speed and direction, often related to the concepts of orbital velocity and escape velocity.

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Suns Orbital speed and escape velocity question

This is a homework question and I don't want an answer but just want to understand what its asking for. We are given that a star with a mass of x solar masses in ...
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Does the universe prefer a velocity?

As I understand it, the distribution of matter is roughly homogeneous across space -- anywhere I stand in the universe, there will about the same amount of matter in every direction around me. Is the ...
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radial velocity fitting of a binary

I have two series of velocities (HJD, $v_{1}$ and $v_{2}$ ), how to fit in detail? There is any formula on the web? $sine$ curve is easy, but I need to consider an eccentric orbit. Suppose we can ...
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Are black holes solely responsible for hyper velocity stars?

I read that the stars orbiting around Sagittarius A* (a.k.a the supermassive black hole located at the heart of the Milky Way) move very fast (many times faster than our Sun moves across the galaxy), ...
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How does one measure velocities of far-off, bright objects

As the title already says, I want to know how one measures velocities of far-off, bright objects, e.g. when the mean parallax drift isn't measurable with current apparatus (this means when there is ...
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In theory, is there anywhere in the universe where velocity=0?

Earth is traveling at a certain velocity. Earth orbits the Sun at velocity X. The sun is orbiting the center of our galaxy at velocity Y. The galaxy is orbiting (something?) at velocity Z. On and ...
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What is $v_{GSR}$

In this paper ("The Apache Point Observatory Galactic Evolution Experiment: First Detection of High Velocity Milky Way Bar Stars") they plot and calculate $v_{GSR}$. $GSR$ stands for Galactic Standard ...
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What is the optimal escape trajectory from near a black hole?

Consider a space ship that is being drawn closer to a black hole. The crew begins to notice the effects, and discovers that they are nearing the black hole. They then manage to halt their ...
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Convert orbital elements to positions and velocities

I've written a quick and dirty n-body simulator, but currently it requires initial positions and velocities. I've been looking for a way to convert Keplerian orbital elements to positions and ...
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How do we calculate the escape velocity of galaxies?

How do we calculate the escape velocity of galaxies? Do we have to know the total mass? What is the escape velocity for Milky Way?
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630 views

What is the standard reference point for measuring speed?

Speed, as we know, doesn't exist without first having a reference point. We then say that the reference point isn't moving at all, and speed is then measured in relation to the reference point. What ...