When astronomers speculate the distance of galaxies are they talking about its

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SUMMARY

Astronomers measure the distance of galaxies based on their current position as observed from Earth, rather than the distance at the time the light was emitted. This distinction is crucial due to the expansion of the universe, which alters the perceived distance over time. The concept of "now" in this context is not straightforward, as it refers to the distance as it appears to us today, excluding any motion that occurred since the light was emitted.

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When astronomers speculate the distance of galaxies are they talking about its...

When astronomers speculate the distance of galaxies are they talking about its distance now or when the light was emitted? Since things are moving and the universe is expanding the distance from the object now is much different then were the object is currently...
 
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Er, well, "now" is not a well-defined concept. The distance is is measured "now" for us here. It is how far the galaxy currently appears to be, which doesn't include any motion since the light we currently see was emitted.
 

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