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Assuming an object with the same density as earth (not very good approximation) then a spherical object with a radius of 2.5 km, would have an escape velocity of about 96 mph. A velocity reached by several MLB pitchers. There are probably several asteroids with a radius near this.


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source I don't think this is complete - there may be objects between Phobos and Vesta. Phobos and Vesta have too little mass to be rounded under their own gravity, so the escape velocity may depend on where you are standing.


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The article 'A practical relativistic model for microarcsecond astrometry in space' (Klioner 2003; caution, very heavy duty maths...) describes the framework which was developed to support the data processing for the ESA Gaia astrometric space mission. This mission has the goal to measure the position (astrometry) of stars and other objects to approx. 20 ...


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The reason the hydrogen and helium (that make up most of the mass of planets like Jupiter) remain as gases and don't condense is essentially the same as any other gas. So I could ask "why don't the nitrogen and oxygen in the atmosphere of the Earth condense?" The reason is that the temperature and pressure in the planet's atmospheres do not favour the ...


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I'm going to give a longer, slightly less accurate answer because this is a fun question. I'll start with special relativity because it's easier to understand. Using a thought experiment the velocity and time dilation relation is not that hard to see and to calculate it, just use Pythagoras. A photon bouncing between two mirrors can be used as a kind of ...


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A physics professor once described the following exchange, and I found it immensely helpful. It's not an exact answer, but the formatting requires an answer post. Question: What is time? Answer: (hover your cursor to reveal) In the context of this question this means that whatever effect you are considering it is an effect on time, not on the clock. ...


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If it has to do something with gravity affecting the inner working of wind up and pendulum clock will this also affect digital clock ? As astrosnapper noted in his comment, gravitational time dilation affects all time-dependent processes. This includes not only clocks (including digital clocks and atomic clocks), but also the rates at which chemical ...


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I think your recreation is essentially correct. For example, if you look at Figure 1 in that paper, you can see that the potential goes from positive to negative as a function of the azimuthal angle ("phase"). What you're missing is that the potential and density functions they define are perturbations, which are intended to be added to an axisymmetric ...


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The following is excerpted from from this answer to the Space Exploration SE question "Do Curiosity's reported measurements of Mars' surface gravity (~3.717 m/s^2) include centrifugal effects?". It essentially answers my question. I would appreciate if someone gave the info about the gravimeter on the Phoenix lander too. So the surface gravity on Mars is: ...


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