The most distant galaxy in the universe
How large is the universe? As large as the most distant object we can detect, might be one answer. But this is not quite true: The most distant visible object only marks the boundaries of the observable universe. This could be GN-z11. A team of astronomers used the Keck I telescope to measure the distance to this ancient galaxy. They found that GN-z11 is not only the oldest galaxy, but also the most distant. It is so far away that it actually defines the boundary of the observable universe itsel...
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Glenn
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Dec 27, 2020 11:28AM
Here is one thing I never understood about the assumed "age of the universe" (13.8 billion years) if we can see the most distant observable universe at 46.5 billion light-years distant. Is that where the expanding space theory comes in?
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Glenn wrote: "Here is one thing I never understood about the assumed "age of the universe" (13.8 billion years) if we can see the most distant observable universe at 46.5 billion light-years distant."Yes, the space between us and the object is always expanding, and ever faster, that's why the light is also moved into the more red part of the spectrum; we don't see it like it was sent but in infrared now.
so is that how they determine the 13.8 billion? how do they calculate the rate of redshift expansion and how do they know the most distant object is 46.5 billion LY away? seems like at least two of the three needed elements is not known for the math.
Glenn wrote: "so is that how they determine the 13.8 billion? how do they calculate the rate of redshift expansion and how do they know the most distant object is 46.5 billion LY away?"It's not that easy because the speed of the expansion is not exactly known for each point in time, only for today. We know that it was slower in the past. So the 46 billion LY is a good estimate. Redshift is easy to calculate because they know the original frequencies, and then we have "standard candles" like Cepheids and Pulsars to get a distance.
