How do distance and age relate in astronomical measurements?

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The discussion centers on the relationship between distance and age in astronomical measurements, particularly regarding light years and redshift. It clarifies that redshift primarily limits the maximum possible age of celestial objects, indicating that a galaxy's age cannot exceed a certain threshold based on its distance. For example, a galaxy like NGC 4921, located 260 million light years away, can be estimated to be around 13.4 billion years old. The conversation highlights the complexity of measuring cosmic distances and ages, emphasizing that redshift does not directly determine age but sets boundaries. Understanding these concepts is crucial for interpreting astronomical data accurately.
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I thought i understood a light year as a measure of distance.But i keep running into articles that say something like ...around Galaxy NCG 4921 there are a cluster of galaxies estimated to be 13+ billion years old at a distance of 320 light years from earth.How do you get that when you are measuring red shifts?
Or how do you get "there are globular clusters that appear older than the known universe?"
Thank you for any help.:confused:
 
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Redshift limits the maximum age of objects in the universe. That is to say that a galaxy 13 billion years old cannot be at a redshift distance in excess of about 700 million light years. Similarly, a galaxy 6 billion light years distant cannot be more than about 7.7 billion years old. So NGC 4921 at a distance of 260 million light years could be 13.4 billion years old.
 


By George,I think i have it.Thank you mothman and Chronos.
 
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