\begin{table}%t2
 \caption{\label{Lines_090510}Emission lines detected in the spectrum of GRB~090510 corrected for Galactic extinction.}
%\centering
\par
\begin{tabular}{lcccc} 
\hline\hline \noalign{\smallskip}
Line  & $\lambda_{\rm obs}$ & $z$ & Flux \\
 & & & ($10^{-17}$ erg cm$^{-2}$ s$^{-1}$) \\
 \hline
\ [OII]$\lambda3727$ & 7092.6 & 0.9030 & $1.30\pm0.15$ \\
\ H$\beta$ & 9249.7 & 0.9028 & $0.50\pm0.15$ \\
\ [OIII]$\lambda5007$ & n.d. & . . . & ${<}0.3$ \\ 
\hline
\end{tabular}
\end{table}