Questions tagged [milky-way]

Questions regarding the Milky Way Galaxy, the galaxy that Earth's solar system is in.

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8
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1answer
441 views

What is the shape (along the plane, not up-down) of stellar orbits in flat spiral galaxies

What I mean is, with a central mass orbits are relatively simple, but orbits around the galaxy are different, in essence as the star orbits through the dark matter halo, the further it moves away from ...
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642 views

What can we expect from the first accurate image of a black hole?

From recent news from the Max Planck Institute for Radio Astronomy: The European Research Council (ERC) has awarded 14 Million Euros to a team of European astrophysicists to construct the first ...
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Are there are any photographs online that approximate what the Milky Way looks like to the unaided eye?

I love seeing all the long-exposure photographs of the Milky Way, but I'm going to Cherry Springs State Park in Pennsylvania next month, and I'm wondering if there are any photos that approximate what ...
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Whereabouts of the Pleiades

I assume they should be in the Milky Way galaxy. I have read about it a little but did not find information on where they are. Which galaxy do the Pleiades belong to?
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910 views

Could the Sun and our Solar System one day leave our galaxy?

I have now learned that the Sun is not fixed in place, so I asked myself this question: It is possible, that the Sun and our Solar System will one day leave our galaxy? If yes, how, and if no, why not?...
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240 views

Why doesn't the black hole in the center of the Milky Way glow similarly to the famous M87 image?

The M87 image made some astronomers famous recently as the first image of a black hole. In the Milky Way, it has been concluded that there must be a black hole due to the movement of stars near the ...
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Is the Sun prograde or retrograde with respect to the rotation of the Milky Way?

I recently learned about the terms prograde and retrograde. I've seen these terms used to describe the rotations and orbits of moons with respect to their planet, and planets with respect to their ...
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In which direction does the ecliptic plane make an angle of 60 degrees with galactic plane?

In which direction does the ecliptic plane make an angle of 60 degrees with galactic plane? Is it toward the galactic center? (It can have any 360 degree orientation.)
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How bright would Sagittarius A* be from Earth if it became an Active Galactic Nucleus?

Essentially I'd like to know how bright our central black hole could appear from earth in relation to full moon brightness. Assuming maximum energy output (like when it's gobbling up an entire ...
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3answers
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Are the stars outside of the galactic plane in the galactic halo?

The majority of the stars we see in the sky, like Pollux, are outside of the galactic plane. That means that all those stars we see are not in the galactic disk, and therefore are in the galactic halo,...
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5answers
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Can the Milky Way be seen with the naked eye? Does this apply to any galaxy? If yes, then how and when?

I have seen different pictures in a different community to showcasing the Milky Way. I can never tell whether it's edited or it's the real picture. Actually, I can never see any galaxy as such by with ...
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416 views

Forms of stellar orbits around the galactic center

Do all stars in orbit around Sagittarius A have approximately circular orbits or are there stars that orbit the Milky Way center very elliptically, like being in the Milky Way's outer rim at apoapsis ...
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Does the Milky Way belong to a Galaxy cluster

I know that the Milky Way is a member of the Local Group and the Virgo Supercluster / Laniakea Supercluster. However, I can't seem to find any information about the Galaxy cluster we belong to. Does ...
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What does the milky way look like from earth to the human eye without light pollution?

Cameras are great, they allow us to compress several seconds of light exposure into a single instant. This allows us to take amazing pictures of the night sky, like this one. Of course you can see we ...
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1answer
114 views

Does the galaxy look like a Web or a Tree?

Suppose we have a distance cutoff $r_0$. Let's say that any two stars in the galaxy with a relative distance below $r_0$ have a path between them. Would the path-connected Milky Way look like a Web in ...
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558 views

Can we see the stars at the edge of the Milkyway?

This question proved much more difficult to formulate than I initially imagined. It concerns how far out in the Milky Way that we actually see with different telescopes. I know the Milky Way disk is ...
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3answers
381 views

How is the Milky Way on a collision course with Andromeda when the universe is expanding? [duplicate]

At some time in the future it is said our galaxy will collide with Andromeda. Yet at the same time the universe is expanding at a ever-accelerating pace. Using the old raisin-in-the-baking-loaf-of-...
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291 views

Collision with Andromeda Galaxy

According to Hubble's law, the universe is expanding and this expansion is proportional to distance between the two objects and thus objects are moving away at a very fast rate, then why is it ...
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201 views

How was the galactic plane established?

As pointed out in this answer the axes of galactic coordinates are defined such that galactic longitude and latitude (0, 0) point toward the galactic center. But then the plane defined by galactic ...
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3answers
4k views

Milky Way position on the sky

I'm looking for some sort of boundary data to be able to render the milky way on a star map, as visible from Earth. Something that looks like this: For that, I need something like a collection of RA ...
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1answer
258 views

Would our galaxy appear as a spiral when seen from the Andromeda galaxy?

I'm wondering how our galaxy is tilted with respect to the Andromeda galaxy. Seen from the Andromeda galaxy, what would our galaxy look like? Would it appear as a spiral, or would it be seen ...
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1answer
125 views

Milky Way as seen by the human eye: where exactly do those photons come from?

I'm asking here about the diffuse glow seen by the human eye, when looking at the Milky Way. Where do those visible photons come from exactly? the surface of a star? starlight bouncing off something ...
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What is in the brightest area of the night sky?

When I look up in the night sky, I assume the brightest area, commonly known as "The Milky Way", is the Galactic Center of our home galaxy. But then I stumbled upon this illustration, which seems to ...
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Opposite Constellation of Sagittarius A*

Suppose an alien race fired a laser beam from the centre of the Milky Way, it went through the Sun and then off further out of the galaxy. What Constellation would the light beam head towards, ...
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2answers
366 views

Difference in energy released in stellar mass black hole merger and supermassive black hole merger

Super massive black holes are usually millions of times more massive than stellar mass black holes. I have read on SE and over internet that 3M☉ worth of energy is released in black hole mergers (not ...
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988 views

Why do pictures of the Milky Way look like a spiral?

When I see pictures of the Milky Way they show a spiral shape. Why is this?
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824 views

What is supposedly in the center of the Milky Way?

It's big. It's bright. It's white. It's so intense. But what is at the center of the Milky Way?
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490 views

How do astronomers calculate the period about the wave motion of the solar system in the Milky Way?

According to research, excluding the motion of the entire galaxy, astronomers found the motion of the solar system in the Milky Way. The solar system revolve around the galactic bulge of the Milky ...
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286 views

Do most astronomers think that Andromeda will collide with Milky Way?

Most astronomers say it is likely to happen. Is this true? Are there any scientists that reject this?
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210 views

Is there a retrograde star that passes closer to the galactic center than our Sun?

Our Sun is moving in a prograde orbit around the galactic center with a distance of about 8 kpc. This paper says there are many retrograde stars in the galactic halo 10-20 kpc from the galactic ...
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482 views

How did the Milky Way and Andromeda Galaxy separate before they began their collision course?

How did the Milky Way and Andromeda Galaxy separate before they began their collision course? I understand that gravity is pulling together the two galaxies, but what separated them in the first ...
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1answer
240 views

Is metallicity low at the central region or nucleus of the Milky Way?

Is metallicity low at the central region or nucleus of the Milky Way? Does metallicity decrease or increase as we move from the center out to the edges of our galaxy?
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4answers
702 views

Why won't the Milky Way colliding with Andromeda affect the Solar System?

According to Wikipedia Such an event would have no adverse effect on the system and the chances of any sort of disturbance to the Sun or planets themselves may be remote. I'm imagining that this ...
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1answer
121 views

Do we know what's “behind the Milky Way”?

If we do, how? And what are those objects on the other side of the galactic center? We can't see through the dense band of light and dust, but maybe in other spectrums the band is much less dense? But ...
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3answers
9k views

What specific parts of the Milky Way do we see when we look up?

I know we can't see the center. But do we see any of the central bulge? Are we just seeing nearby stars in the Orion Spur where we are? In the Sagittarius Arm? In the other direction, are we ...
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1answer
532 views

Has a “white hole” theory been advanced to explain anomalous star formation in Sagittarius A?

In 2008, the European Southern Observatory reported, upon the end of a 16-year study described here http://www.eso.org/public/usa/news/eso0846/, that the 28 stars nearest the very large black hole in ...
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1answer
132 views

What is the distribution of organic compounds in the Milky Way Galaxy?

I imagine the answer is unknown for the entire galaxy, but I would appreciate a notion of the scales and locations of regions where astronomers have ventured at least a guess to the distribution of ...
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1answer
888 views

Number density of stars on the Galactic plane

The number density of stars (e.g. the number of stars per cubic parsec) is given by $$N(z) = N(0) e^{-|z|/h}$$ where $z$ is the height above the Galactic plane, $h$ is the scale height for a specific ...
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280 views

Is there evidence for galactic “seasons”?

The Solar Year has huge effects on our climate, and the signs of passing seasons are physically evident on Earth. I recently learned about the Galactic Year. To my understanding, our sun orbits the ...
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1answer
56 views

How many horizontal branch stars are within 2 kpc of the sun?

For my research purposes, I am wondering how many horizontal branch (HB) stars are within 2 kpc of the sun? I tried to find some with the Gaia DR2 data with a magnitude cut that leaves HB stars out ...
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1answer
2k views

Solar system data API?

I'm prototyping a real time solar system / milky way discovery app. Could you please help me on: -What is the best orbital data public API I can use? -What is the standard numerical way to define ...
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1answer
95 views

What parameters determine whether galaxies colliding will result in a merger or a hit and run?

Colliding galaxies sometimes merge and sometimes pass through each other. Either way, there are huge changes as a result. What are the parameters that matter in determining whether a collision will ...
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143 views

How far have stars been seen beyond the center of the Milky Way?

What lies near the center of the galaxy is of great interest and in recent times the motion of dozen(s) of stars at the center of our galaxy orbiting around Sgr A* have been measured in great detail. ...
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696 views

Observing the motion of the solar system and galaxy through space?

This is very perplexing. Conditions: planets are moving around the sun (solar system) solar system is moving as part of the galaxy the galaxy is moving through space on some axis galaxy is part of a ...
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Is Zeta Reticuli within the Orion Arm?

My research has told me astronomers have labeled the galaxy arm that our system is located the Orion Arm but I have yet to find out if that also applies to Zeta Reticuli or not (not asking about ...
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2answers
127 views

What is the mean separation between a star and its closest neighbor in the Milky Way halo?

My question is inspired by this previous question, Are there any stars that orbit perpendicular to the Milky Way's galactic plane?. In the great answer posted by @ConnorGarcia, one commenter said he ...
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2answers
1k views

Why the Milky Way appears to be arching across the sky?

The Milky Way galaxy is disc-shaped and earth is in its plane: (source) In the following image the milky way appears to be arcing across the sky: (source) This looks like an out of plane view of ...
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1answer
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Is the Large Magellanic Cloud contained in the Milky Way?

From a distance of 160,000 light years, the Large Magellanic Cloud looks at first glance like an isolated section of the Milky Way, running across southern Dorado into neighbouring Mensa. Is the ...
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1answer
136 views

How big is the galactic magnetic field in the solar system and how can we measure it?

The Milky Way has an associated magnetic field. But how big is it influence in the solar system and can we measure it? I mean, when measuring, how can we make the distinction between the field of the ...
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3answers
467 views

Apparent magnitude of Milky Way?

We have apparent magnitude of stars, planets, DSOs. What about the apparent magnitude of Milky Way? Can it be estimated?