deletions | additions       diff --git a/figures/fig_for_inclass_nova1/caption.tex b/figures/fig_for_inclass_nova1/caption.tex  index 823690b..f3cd26e 100644  --- a/figures/fig_for_inclass_nova1/caption.tex  +++ b/figures/fig_for_inclass_nova1/caption.tex 
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\noindent \emph{2) Estimate the standard deviation of the background ($\sigma$), and explain your reasoning.}\\  \noindent \emph{3) Estimate the peak flux density of the nova ($S_{\rm max}$), ($S_{\mathrm{max}}$),  and explain your reasoning.}\\ \noindent \emph{4) Astronomers usually only take detections seriously if they are 5 or more $\sigma$ significant---that is, if the detected source is at least five times brighter than the   standard deviation of the background. In other words, the source's peak flux should be $S_{\rm max} $S_{\mathrm{max}}  > (\bar{S} + 5 \sigma)$. Estimate how many sigma the peak flux density of the nova is, and show your reasoning. Would this detection be taken seriously by other astronomers?}