Questions tagged [milky-way]
The milky-way tag has no usage guidance.
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What will happen to the Milky Ways nucleus when Andromeda collides with the Milky Way?
Andromeda will collide with the Milky Way in about 4.5 billion years. What I want to know is, will the Milky Ways nucleus reactivate when we collide with Andromeda, will it combine with Andromeda's ...
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Does going to the other side of Milky Way galaxy mean seeing different observable universe?
What if there was a robot that got sent to the other side of the Milky Way by just traveling with a fusion engine and started orbiting a planet that has around Earth's gravity in order to avoid any ...
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If the expansion of space causes the elongation of light waves, why isn't this elongation observed within the Milky Way?
The elongation of light waves occurs not because galaxies are moving away from each other, but because light waves are stretching along with the fabric of expanding space (cosmological redshift). ...
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Size and boundary of the Milky Way Galactic disk
I have been pondering a question that arose while I was reading a research paper that mentions galactic disk stars have been found up to distances as far as 25 kpc from the galactic center and ...
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How do we know that we will collide with Andromeda? [duplicate]
We know that Andromeda galaxy is heading towards the Milky Way. But how do we know that Andromeda doesn't have a large Transverse velocity? This would cause the Milky Way and Andromeda galaxies to ...
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How much gravitational lensing do we see from the Milky Way?
I assume that the Milky Way has a dark matter halo just like any other. If that is the case, if we look at a huge part of our own galaxy, do we actually see the gravitational lensing effect? How ...
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What's the nearest star that could go Supernova in the near future?
https://en.wikipedia.org/wiki/IK_Pegasi B is the nearest supernova candidate, but that white dwarf that's part of the system won't go supernova for around 2 billion years.
What's the nearest star that ...
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How can I make the equation of warped disk?
My teacher gave us the assignment to find the moment of inertia of any shape you want. So I decided to find the moment of inertia of our milky way galaxy.
I found out that our galaxy is shaped like a ...
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Identifying the Milky Way uniquely [closed]
Let’s suppose you wanted to elegantly represent the Milky Way in a minimalist fashion in a way that would make sense a billion years hence (ie let’s set aside the damage wrought by colliding with ...
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Is sun orbiting the center of the Milky Way? [closed]
Are all the celestial bodies in our galaxy (along with the Sun) orbiting the center of the Milky Way Galaxy?
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Has MOND been tested or even confirmed for our own galaxy, the Milky Way?
MOND, based on a modifications of Newton's law for small accelerations, describes the rotation curves of stars in most galaxies, especially the outer stars.
Has MOND been tested for the stars in our ...
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What definition of now is used in our stellar neighbourhood?
Within General Relativity the idea of simultaneity is fairly arbitrary, every coordinate system has one. Which one corresponds to my personal local sense of now appears indefinable in any objective ...
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Does the Milky Way have any impact on Earth?
Does which galaxy we are in (Milky Way) have any impact on Sun/Earth?
What I mean is: suppose our solar system was instantly teleported into a different galaxy (eg Andromeda). Apart from the stars ...
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About the non-intuitive announcement at 12 May 2022 of the EHT team that spin axis of Sgr A* Black Hole facing Earth?
What is this all about?: At 12 May 2022 at the ESO official announcement live streaming event the EHT representatives claimed that the Sgr A* BH accretion disc spin axis is sort of facing Earth's ...
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Why are there three bright spots in the first picture of Sagittarius A*?
Why are there 3 distinct bright spots? The picture of the black hole in M87 had half bright and half dark, which I believe is a result of the different relative velocities of particles orbiting it, (...
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Are there tidal forces between the solar system and the galactic centre?
Tidal forces are experienced within a system moving in free fall around a bigger object because of the different strength of gravity over the system. The difference can be calculated between the far ...
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Are we totally limited to the Milky Way for all stellar astrophysics?
Simply put;
Are we able to make any observations of the individual stars in other galaxies?
Is the depth of our scientific knowledge on star systems, based solely on stars in the Milky Way Galaxy ...
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How large are the fictitious forces due to our orbit around the galactic center?
When we are in a non-intertial system, this creates fictitious forces. Some well-known fictitious forces are the centrifugal and coriolis forces. Those are caused by the Earth's spin around its axis.
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How many full orbits around the galactic center our Earth has done so far since its creation?
I have read that the estimated age of our Milky Way galaxy is 13.61 billion years which is by using our current size and status of our galaxy about 59.17 Galactic years which each galactic year ...
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How did astronomers at Edwin Hubble time decide the size of the Milky Way Galaxy and settled the Great Debate?
I have been reading some books about Great Debate that whether the Milky Way Galaxy was the entire universe and Edwin Hubble settled the debate by identifying some Cepheid variable star (V1) in ...
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Is there cosmological redshift within the Milky Way?
Cosmological redshift is based on the idea that the universe is expanding. When the universe doubles in size, or scale factor, the wavelength of light doubles. But the Milky Way is not expanding so my ...
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Can somebody describe the frame dragging around Sagittarius A at the center of our galaxy?
I need to be able to visualize it, specifically the number of turns and how it relates to the horizons in the black hole and what would happen to something falling in also described. Has anyone ever ...
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How is speed of Milky Way determined relative to CMB dipole?
I read that our galaxy the milky way is moving at approx 630km/s relative to CMB dipole, I think they applied Doppler shift to find this number but how do they do that? I know when universe is a hot ...
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Estimating of the size of the Milky Way from the Sun's motion
I am trying to run a simple first-principles calculation to estimate the diameter of the Milky Way from what we know about the motion of the Sun around its center. In particular, from various online ...
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Do we have to care about the force from the Milky Way black hole while analysing the Solar system from its Center of Mass frame?
And also while analysing Earth's spinning motion about its center? Do we have to care about the forces from the giant Black Hole at the center of Milky way?
I guess we would have to take the Black ...
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Will Milky way and Andromeda collide for sure?
Is it sure that Milky way and Andromeda will collide or might they just start a rotation around their center of masses?
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What is the luminosity of the Milky Way?
This question may appear to be the same as What is the luminosity of the Milky Way galaxy?, but that question references a value of $5\times 10^{36}\space W$, which comes from a Wiki page which ...
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Why is the Andromeda galaxy coming closer to Milky way?
If both these galaxies are on collision path because of their gravity but how could that be?
They are 2.5 million light-years apart now but I imagine they are still n collision path for a long time ...
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What's the energy of all the light/electromagnetic radiation in our galaxy?
I came upon this question while watching a pop-sci video on youtube about Dark Matter and thinking about all the things that could be contributing gravitational influence to a galaxy.
From relativity ...
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How will Andromeda collide with Milky Way in spite of Hubble's law? [duplicate]
According to Edwin Hubble our Universe is expanding because he noticed that other galaxies are moving away from us. But then how Andromeda galaxy will collide with Milky Way in ~4.5 billion years, as ...
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Where can I find visible/radio telescopic observations of the center of the Milky Way galaxy?
I recently stumbled across this time-lapse telescopic image (radio image, I believe) of the center of the galaxy.
Here's a still image. Link to time-lapse video below.
I haven't been able to find ...
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Will the Sun's orbit around the Milky Way degrade once it transitions to a white dwarf with half its original mass?
Does the Sun's mass factor in at all when it comes to its orbit around the Milky Way, such that if it lost half its mass, its orbit would change? Or is it a matter of the center of the Milky Way being ...
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Why was the imaging of M87 black hole easier than imaging the Milky way's Sagittarius A*? [duplicate]
In the recent EHT press release of the image of the super massive black hole at M87, I am curious to know why the super massive black hole at the centre of milky way has not been imaged yet.
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Milky Way Density
It seems to be a simple question, but I wasn't really able to find an appropriate answer: How dense is the Milky Way? I am certain that there are reliable statistic, maybe even new ones from the GAIA ...
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What's the eccentricity of our sun's orbit around the center of the galaxy? [duplicate]
Just thinking about "galactic habitability zones." Is this even a valid question?
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Dark matter density calculation
I find that the general dark matter density of the Milky Way is $$6.87 \times 10^9 \: \rm GeV/m^3$$ or $$1.225 \times 10^{-17} \: \rm kg/m^3$$ (by taking the size of the Milky Way and dividing it to ...
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What does the gravitational potential of the Milky Way do to the CMB?
We sit in a gravitational potential, so there should be a blue shift on the CMB light from the potential of the Milky Way. Is this blue shift dependent on direction? Is it being subtracted from the ...
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Is it possible to see the Milky Way galaxy through a gravitational lens? [duplicate]
I have been thinking about these amazing images of ancient galaxies we can see because of gravitational lensing. Some of them even have multiple images of the same galaxy in two different places ...
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Does the Sun revolve around the supermassive black hole at the center of the Milky Way? [duplicate]
I'm curious to know, does the sun really revolve around the black hole at the center of the galaxy?
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Path to a distant star
Suppose we have a space ship that can go fast enough (0.9c) and we have plenty of time, and we want to travel to a star on the other side of the galaxy. How do you plot a path to navigate to that star?...
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What is the evidence for a supermassive black hole at the center of Milky Way?
Black holes cannot be seen because they do not emit visible light or any electromagnetic radiation. Then how do astronomers infer their existence? I think it's now almost established in the scientific ...
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Estimating total mass inside the Sun's orbit
I'm trying to estimate the local density of dark matter at a given radius, $r=R_0=8\text{kpc}$. I also have values for the core radius, $a=5\text{kpc}$, and circular velocity of the Sun, $v_{\text{...
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Milky way without black holes in the center [closed]
I understand that the Milky way is a spiral galaxy with a supermassive black hole in the center.
I understand that because of the stress-energy and the gravitational field of the black hole, the ...
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The Sun's Orbit - Is it What We Think?
I was thinking that the sun must orbit something within our spiral arm in the Milky Way, or be affected by other astronomical bodies - surely not just the supermassive black hole centre.
I have ...
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What is the current shape of the Milky Way?
Things in the Universe which are thousands of light years away from Earth can be seen, or pictures can be taken by Hubble Telescope, because those stars, galaxies, etc. emitted light thousands, ...
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Is there a Neutron Star or Black Hole close to solar system?
I recently read an article where it mentioned that the solar system could be born out of a supernova explosion (death of a previous star). In case there was a supernova, wouldn't there be a ...
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What is the local stellar number density?
Is it just me or does this paper, while providing a great equation for the behaviour of the general stellar number density, never actually give a value for the local stellar number density $\rho(R={\...
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If our galaxy's dark matter halo is so large and diffuse, why is the ordinary matter in it so much more localised and compactly located?
I just read that our galaxy's dark matter halo is estimated to be 1.5m ly across, compared to the visible galaxy's 100k ly across, needed to explain stellar rotation curves.
Why would this be? By ...
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If the Universe is expanding, then why will Andromeda collide with the Milky Way? [duplicate]
Andromeda is moving towards the Milky Way Galaxy at around 250,000 mph, but I wonder what is the direction of our Milky Way Galaxy? Are these two galaxies heading towards each other or Andromeda will ...
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Frame Dragging by Sag A star
Is frame dragging by the supermassive black hole Sag A responsible for the milky way's rotation? If so would we also be part of time dilation depending on how close we are to Sag A? Is the gravity ...
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