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Fraser
2016-Nov-01, 09:50 PM
Did you hear that the Universe has 10x the number of galaxies? How did astronomers discover this, and what does it mean for the number of stars?
The post How Many Galaxies Are There in the Universe? (http://www.universetoday.com/30305/how-many-galaxies-in-the-universe/) appeared first on Universe Today (http://www.universetoday.com).


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George
2016-Nov-04, 07:01 PM
The galaxy count in the Hubble Extreme Field was discussed somewhere around here and, extrapolating, yields 175 billion galaxies. Using a little over 100 billion stars per galaxy -- those very distant ones should have fewer stars on average due to their younger age -- we can get a nice answer as to the number of stars that's easy to remember...

2E22

Assuming we are off by a factor of 30 -- the James Webb might help with this -- then we will have a nice and tidy number to work with - 6E23, making Avogadro more proud.