The configuration of galaxies in space

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Discussion Overview

The discussion revolves around the configuration and alignment of galaxies in space, specifically focusing on the Milky Way and Andromeda galaxies. Participants explore how Andromeda's position relates to the Milky Way and other nearby galaxies, considering celestial coordinates and visual representations.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • One participant questions the alignment of the Andromeda Galaxy relative to the Milky Way, proposing two potential positions (P1 and P2) and inquiring about its plane alignment.
  • Another participant suggests searching for information and images of the "local group of galaxies" to gain a better understanding of their configurations.
  • A different participant recommends using a database of extragalactic objects to find galactic coordinates, explaining how these coordinates can help visualize the position of galaxies relative to the Milky Way's plane.
  • One participant shares specific galactic coordinates for Andromeda, indicating that it lies slightly below the Milky Way's plane and away from its center.
  • Another participant expresses difficulty in finding images that clarify the orientation and alignment of galactic planes, sharing an image that they believe is relevant.

Areas of Agreement / Disagreement

Participants have not reached a consensus on the exact configuration of the Andromeda Galaxy relative to the Milky Way. There are multiple viewpoints regarding its alignment and the interpretation of celestial coordinates.

Contextual Notes

Some participants express uncertainty about how to interpret celestial coordinates and their implications for galactic alignment. There are also mentions of varying methods for visualizing galaxy positions, indicating a reliance on different tools and sources.

PainterGuy
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TL;DR
How to find the alignments for different galaxies in sky? If they are horizontally aligned, vertically aligned, or skewed or tilted when viewed from Earth.
Hi,

In the picture below, M is Milky Way Galaxy in red, both A's are Andromeda Galaxy in positions P1 and P2 , and W is some random galaxy.

Milky Way Galaxy lie in one plane just like all the planets in solar system. In what configuration Andromeda Galaxy lies? Does it lie almost at the same level as Milky Way Galaxy? For example, the W galaxy lies in almost in the same plane as Milky Way. Does Andromeda lie in position P1 up above the Milky Way but its plane alignment is the same as Milky Way? Or, does Andromeda lie in position P2 where it's aligned along z-axis?

Wikipedia page, https://en.wikipedia.org/wiki/Andromeda_Galaxy, does give the coordinates, capture at the bottom, for it but I don't know how to interpret celestial coordinates, and if celestial coordinates convey any info about its alignment.
1646123696150.png


1646124986503.png
 
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You could search for information and images of the "local group of galaxies".
 
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For nearby galaxies PeroK's suggestion would be the easiest and most intuitive.

If you want to picture any galaxy in general, you can go to a database of extragalactic objects, such as this one: https://ned.ipac.caltech.edu/ and search for the name of the object (common name, designation in Messier, NGC, anything should do). Keep in mind the database queries may take a few seconds to process.
It'll display a set of data, including galactic coordinates (latitude and longitude). Galactic coordinates allow for easy picturing where in relation to the plane of the Milky Way does any object lie.
The longitude (l) and latitude (b) are measured like so:
1646142609195.png

With galactic north being towards the constellation of Coma Berenices and 90 deg longitude in the direction of the Sun's orbital motion through the galaxy, roughly towards the star Deneb.

E.g. for Andromeda the database returns l=121 b=-22 so it's a bit below the plane and a bit away from the galactic centre.

Another visualisation option is to use a planetarium software (e.g. Celestia), and find galactic coordinate grid in the display options before searching for the object.
Or, of course, going out at night and finding where the object lies w/r to the band of the Milky Way (i.e. its plane) and its centre in Sagittarius.How much an object is oriented edge-on or face-on can usually be readily seen from the pictures.
 
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PeroK said:
You could search for information and images of the "local group of galaxies".
I did try to search for some images but it didn't make much sense and wanted to get a general idea to know the orientation and alignment of a galactic plane.

I think the following image comes close to it. One can Andromeda from Earth and its center is also visible,

1646190114095.png

Source: https://ourplnt.com/andromeda-brighter/
 
We were thinking something more like this:
1646233931346.png
 
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