Sky seen from a planet orbiting a star in intergalactic void

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Discussion Overview

The discussion explores the appearance of the night sky from a planet orbiting a star that has been ejected from a galaxy, particularly focusing on the visibility of other galaxies and stars in an intergalactic void. Participants consider various scenarios regarding the distances to nearby galaxies and the implications for what might be seen from such a location.

Discussion Character

  • Exploratory
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants suggest that a star ejected from a galaxy would not differ significantly from stars within galaxies, and a planet could orbit it, leading to questions about the visibility of galaxies in the night sky.
  • One participant proposes that if the star is located halfway between the Milky Way and the Canis Major Dwarf galaxy, the night sky might appear similar to how it does from Earth, with the Milky Way visible as a band across the sky.
  • Another viewpoint indicates that distant galaxies would likely not be visible as distinct points of light, but rather as faint smudges, with individual stars difficult to resolve due to their distance.
  • Some participants express uncertainty about the visibility of galaxies, noting that light pollution and other factors could affect what is seen from such a planet.
  • There is a discussion about the effects of a star's ejection on its orbiting companions, with one participant likening gravity to politics, emphasizing its local nature.

Areas of Agreement / Disagreement

Participants express differing views on the visibility of galaxies and stars from the proposed location, with no consensus reached on how the night sky would appear. Some argue that galaxies would be too dim to see clearly, while others suggest that certain features might still be visible.

Contextual Notes

Participants acknowledge the limitations of human vision and the impact of light pollution on visibility, which may vary significantly depending on the observer's location.

Who May Find This Useful

Individuals interested in astrophysics, observational astronomy, and the nature of intergalactic space may find this discussion relevant.

FtlIsAwesome
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A star that has been ejected from a galaxy probably wouldn't be any different from stars within galaxies. It could be possible for a planet to orbit this star. What would the night sky appear like? Would the galaxies be too dim to see, and the night sky fully black?

Lets say that the star is halfway between the Milky Way and the Canis Major Dwarf galaxy, the nearest galaxy at 25,000 ly away. How would the Milky Way look like from the star's planet?
 
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FtlIsAwesome said:
A star that has been ejected from a galaxy probably wouldn't be any different from stars within galaxies. It could be possible for a planet to orbit this star. What would the night sky appear like? Would the galaxies be too dim to see, and the night sky fully black?

Lets say that the star is halfway between the Milky Way and the Canis Major Dwarf galaxy, the nearest galaxy at 25,000 ly away. How would the Milky Way look like from the star's planet?




An intergalactic region doesn't place us out of range of the home galaxy or any other galaxy so galaxies could still be detected via optical or radio telescopes.. In fact, our own galaxy is right now in what can technically be called intergalactic space since it is between millions of other galaxies. The region between Canis Majoris Galaxy and ours would leave the sky pretty much as it is from a purely numerical star and galaxy observation standpoint.
 
FtlIsAwesome said:
Lets say that the star is halfway between the Milky Way and the Canis Major Dwarf galaxy, the nearest galaxy at 25,000 ly away. How would the Milky Way look like from the star's planet?

It would be rather boring to the naked eye. Chances are, individual stars would be difficult to resolve because of their distance, and you would just end up with a "milky way" type feature extending across a good portion of the sky. Other galaxies, such as Andromeda and the Magellanic clouds, would look much the same as we see them here on Earth.
 
Ok, I admit I phrased my question bady.
So I'll ask a slight different but related question.

If someone was halfway between Milky Way and Andromeda, distant galaxies would not be visible like stars, correct?
I used to think that someone would see a sky filled with points of light from the distant galaxies like stars do here, but galaxies are too dim.
 
FtlIsAwesome said:
Ok, I admit I phrased my question bady.
So I'll ask a slight different but related question.

If someone was halfway between Milky Way and Andromeda, distant galaxies would not be visible like stars, correct?
I used to think that someone would see a sky filled with points of light from the distant galaxies like stars do here, but galaxies are too dim.

You've seen the Andromeda Galaxy, have you? A small faint smudge visible to the naked eye on a clear night.

If you were half way between Milky Way and Andromeda, I think that at night (assuming only human vision capabilities) you'd probably be able to see one or the other as a not-quite-so-faint smudge in the sky. Nothing else would be visible to the naked eye.
 
Ejection of a star from a galaxy would probably not have much effect on its orbiting companions. Gravity is like politics - it's mostly local.
 
Chronos said:
Gravity is like politics - it's mostly local.
Hehe...


You've gone on a historical expidition in the archives haven't you? :wink:
 
Jonathan Scott said:
You've seen the Andromeda Galaxy, have you? A small faint smudge visible to the naked eye on a clear night.
Caveat: with pollution and light polution, I wouldn't bet that all that many people have seen the Andromeda galaxy, so while the rest of your explanation is correct given that assumption, for a city/suburb dweller on such planet, the sky may appear completely empty.
 

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