Questions tagged [velocity]
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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Determining the speed of meteor
How to determine the velocity of a meteor from two video data?
I want to try to determine the orbit of the meteor, but before that I have to determine the meteor's entry velocity and apparent radiant ...
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Does the escape velocity formula take into account how a gravitationally bound object's distance to its primary increases before coming back down?
Confusing title, I know. Imagine a perfect, homogenous sphere with an exact radius of $1,000 \text{km}$ and an exact mass of $8 \times 10^{15} \text{kg} $.
If you use the formula for escape velocity $...
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Deriving the Tully-Fisher relation from the virial theorem
So I know this is a loose proof and a lot of assumptions are made, but I do not understand how these assumptions lead to the quantities we obtain so I will be asking questions at each step:
start with ...
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The preferred way of binning (classifying) data for galaxy snapshots in Python
Let's say I have a galaxy snapshot that I load with some package (pynbody etc) and I store my spatial coordinates of stars in the galaxy in x, y, z arrays and also velocity in array vz. Now I want to ...
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How are CMB frame redshifts of galaxies corrected for coherent flows?
Say, if I downloaded the CMB frame redshifts of some galaxies from NED database, then what is the procedure to correct it for coherent flows?
I'm using the SNooPy(snpy) Python package to analyze some ...
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How long is the sunrise (or sunset) on North (or South) Pole? [duplicate]
I wonder how to calculate the duration of the Sun crossing the line of the horizon on equinox on Pole. For equator I used this formula:
$t = \frac{2 \times p}{\cos(\phi) \times u}$, where $u$ - is ...
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Can a planet with no atmosphere be orbited at extremely low altitudes?
Can a planet that has absolutely no atmosphere be orbited by a spacecraft at extremely low "altitudes" (if you'd even call it altitude at such a low orbit.
For instance, if this planet's ...
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How to calculate orbital velocity of binary star?
I am trying to simulate the Alpha Centauri AB System. I built the simulation, it works flawlessly when trying to simulate our solar system, and I am now trying to simulate the AB System. I found all ...
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How to find x-values of fourier-transformed correlation functions in velocity space?
I am trying to extract the kinematic parameters (rotation velocity, velocity dispersion, ...) of an elliptical galaxy by extracting the kinematical broadening function using the FCQ-Algortihm first ...
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How to calculate mean line of sight velocity of stars after rotation of galaxy?
I am trying to calculate the mean line of sight velocity from a simulation snapshot of a galaxy after the galaxy is inclined by a certain angle, theta. I am coding it in python.
What I have done so ...
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Why does light accelerate instantaneously to c, while no other phenomena do it? [closed]
In physics, it always takes some time for a particle to move from rest to some speed.
However, photons (light particles) accelerate instantly from zero to c. How? (A visualization would be helpful.)
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Flux vs. Velocity representation of spectra?
I'm looking for a basic explanation of the flux vs. velocity representation of a spectrum and how it's obtained from the regular flux vs. wavelength representation. A good example of this is in Arav ...
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Why collisions between earth orbiting satelites do occur?
According to Kepler laws all earth orbiting satellites should have the same velocity. So how can they collide?
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can i use heliocentric velocity as a rotation speed? [closed]
In the research of the galaxies, does heliocentric velocity involves space's expanding velocity? and can i use heliocentric velocity by galaxy's rotation speed?
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How to find the shape of an orbit
What is the minimum information I need to be able to draw the shape of an orbit of a body that orbits the sun? With this information how can I figure out the shape of its orbit?
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