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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Which software is appropriate to integrate radial velocity with respect to time [closed]
I'm a high school student and currently I'm trying to use Baade-Wesselink method to independently derive period-luminosity relation of Cepheid variables. I noticed that to get the linear radius ...
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Integrating radial velocity with respect to time
I'm a highschool student who is writing a research paper about plotting Period-Luminosity graph of the Cepheid variables by deriving distance through independent method such as trigonometric parallax ...
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How was the acceleration calculated for this CME (Coronal Mass Ejection)?
I am looking at data used in a project to get the velocity and acceleration of a CME (Coronal Mass Ejection). I understand how the velocity was calculated, and for the acceleration, I get the v2-v1 ...
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Is the radius used in the formula for the escape velocity the average radius of the celestial object or the radius at the starting location?
I learnt that the escape velocity is given by $$v_e = \sqrt{\frac{2GM}{r}}$$
Say I want to launch a rocket from the earth into space and want to calculate the escape velocity $v_e$ (I guess without ...
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How do I apply a velocity shift to a wavelength array with uniform logarithmic spacing?
Suppose I have a wavelength array for a spectrum in units of Angstroms. Suppose further that the wavelength has "uniform logarithmic spacing" such that if I just take the difference in Angstroms ...
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Question regarding the Milky Way when calculating galactic space velocities for galaxies
I have been calculating galaxy space velocities (where proper motions are known) in order to measure their orbits of the Milky Way using the method proposed in the appendix of http://www.aanda.org/...
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Can we tell how fast bodies are moving away by measuring their frequency?
It's clear the universe is expanding because light from distant bodies, like galaxies, are shifted towards the red side of the spectrum. In other words, the light measured is more red than it should ...
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How do I modify redshifts to gain corrected line of sight velocities?
I'm currently trying to collect the data to run an N-body simulation for 11 of the galaxies in the Local Group where proper motions are known, however I don't understand how to get the required line ...
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The moon: how to determine its size, speed and distance from earth using a simple telescope?
Assuming I only have a simple telescope, how can I determine the size of the moon, its angular velocity and distance from earth?
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How to calculate the heliocentric velocity of an object?
My task is to calculate the heliocentric velocity of an object to correct for wavelength in a spectrum. I have the RA, Dec and observation date, and I know that the NED velocity correction calculator(...
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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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