\begin{table}%t7
\caption{\label{variable}Possible variable stars in the Hercules dSph galaxy identified in Sect.~\ref{varia}.}   
%\centerline
{                             
\begin{tabular}{c c c c c }          
\hline\hline                        
ID & RA(2000) & Dec(2000) & $V_0$ & $(b-y)_0$ \\    
\hline                                  
11718 & 247.84445 & 12.60114  &  $ 20.44 \pm     0.02$  &    $0.44  \pm    0.04$      \\
22960 & 247.45022 & 12.59089  &  $ 20.19 \pm     0.02$   &   $0.33  \pm    0.04$      \\
33388 & 247.74828 & 12.96788  &  $ 20.38 \pm     0.04$    &  $0.13   \pm   0.06$      \\
41701 & 247.78819 & 12.78892  &  $ 20.74 \pm     0.03$   &   $0.36  \pm    0.04$      \\
41807 & 247.77753 & 12.76208  &  $ 20.34  \pm    0.02$   &   $0.14  \pm    0.04$      \\
42113 & 247.74934 & 12.76745  &  $ 20.41 \pm     0.02$   &   $0.25  \pm    0.04$      \\
42503 & 247.71592 & 12.77974  &  $ 21.78  \pm    0.04$   &   $0.05  \pm    0.06$      \\
43193 & 247.64148 & 12.79060  &  $ 20.54  \pm    0.03$   &   $0.39 \pm     0.04$      \\ 
\hline
\end{tabular}}\medskip
\par
Column 1 lists the INT ID. Columns 2 and 3 list their coordinates. Columns 4 and 5 list the Str\"omgren magnitude $V_0$ and colour $(b-y)_0$ and their associated errors, respectively.
\end{table}