deletions | additions       diff --git a/Updating Drake Eq.tex b/Updating Drake Eq.tex  index 40b0cab..f1c12c9 100644  --- a/Updating Drake Eq.tex  +++ b/Updating Drake Eq.tex 
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First a lot has happened since 1961. Some of the terms in the Drake equation are now known, so we can get a simpler form.  $R$, the \textbf{rate of star formation} tells how many stars are born every year in our Galaxy. This number is about 10 and might seem quite small, but the Galaxy is about 10 billion years old, so plenty of stars have born (and died) in the meanwhile. So $R\approx 10$.   $f_p$ Represents the \textbf{average number of planets around a star}.