Theoretical Question about Milky Way

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SUMMARY

The discussion addresses the misconception regarding observing the Milky Way from a historical perspective. It clarifies that while light from various parts of the Milky Way takes time to reach us, we cannot observe our galaxy as it was billions of years ago due to its proximity. The center of the Milky Way is approximately 30,000 light-years away, meaning we see light that left the center 30,000 years ago. Additionally, the expansion of the universe does not affect the scale of galaxies, which remain relatively stable in their structure.

PREREQUISITES
  • Understanding of light-year as a measurement of distance in astronomy
  • Basic knowledge of the structure of the Milky Way galaxy
  • Familiarity with the concept of cosmic microwave background radiation
  • Awareness of the principles of cosmic expansion
NEXT STEPS
  • Research the implications of light travel time in astronomy
  • Explore the structure and components of the Milky Way galaxy
  • Learn about cosmic microwave background radiation and its significance
  • Investigate the effects of cosmic expansion on galactic formations
USEFUL FOR

Astronomy enthusiasts, astrophysicists, and students studying galactic structures and cosmic phenomena will benefit from this discussion.

Valcken
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This may be a stupid question, but it just popped up in my mind a few minutes ago. Considering we are able to "look back in time" so to speak, because light takes so long to get here, is it possible for us to look in the night sky and see light that came from the Milky Way?

Considering the universe is expanding, and has been expanding ever since it began, wouldn't it be possible to say, look at the cosmic microwave background and actually see our galaxy as it was a few billion years ago?
 
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It doesn't work like that.
We are in the middle of the galaxy, about 30,000lyr from the center - so when we look at the center we see light that left there 30,000 years ago.
The most distant bits of the milky way are about 100,000lyr away
The universe expansion doesn't do anything on the scale of a galaxy.
 

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