\begin{table}%t2
\caption {\label{table2}Absorption redshift of knot A: $\lambda_{\rm meas}$ is the measured wavelength, 
$\lambda_{0}$ is the rest-frame wavelength, $z$ is the measured redshift and $\Delta z$ is 
the redshift difference with NGC~1097 ($z= 0.0042$ NED). } % title of Table
%\centering
 % used for centering table
\begin{tabular}{c c c c c c} % centered columns (4 columns)
\hline\hline 
\noalign{\smallskip}
Line & $\lambda_{\rm meas}$ & $\lambda_{0}$ & $z$ & $\Delta z$ & {\it EW} (\AA)\\ % table heading
\hline % inserts single horizontal line
H$_{\alpha}$  & 6592.0 & 6562.8 & 0.0044 & 0.0002 & 2.9\\ 
H$_{\beta}$  & 4882.1 & 4861.3 & 0.0043 & 0.0001 & 3.8\\
H$_{\gamma}$  & 4359.1 & 4340.5 & 0.0043 & 0.0001 & 2.3\\
\hline %inserts single line
\end{tabular}
\end{table}