Article from the website space.com.
"Billions and billions" of stars in a galaxy (after a quote often mistakenly attributed to Carl Sagan) is how many people imagine the number of stars you would find in one. Is there any way to know the answer for sure?
"It's a surprisingly difficult question to answer. You can't just sit around and count stars, generally, in a galaxy," said David Kornreich, an assistant professor at Ithaca College in New York State. He was the founder of the "Ask An Astronomer" service at Cornell University.
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