\begin{table}%t1
%%\centering
\par
\caption {\label{tab:uvot}Log of UVOT observations.}
%\centerline
 {\begin{tabular}{ccc}
\hline\hline
UTC start date & Exposure (ks) & $U$-band flux density \\
\hline
2006-10-27 05:55:49 & 1.007  & $(4.6\pm1.0)$\\
2006-10-30 06:15:23 & 1.090  & $(5.9\pm1.0)$\\ 
2006-10-31 06:21:27 & 1.084  & $(4.2\pm1.0)$\\
2008-02-10 16:22:46 & 0.484  & $(5.6\pm1.2)$\\
2008-02-12 16:24:40 & 0.925  & $(3.9\pm1.1)$\\
\hline
\end{tabular}}
\par
\smallskip
% \hspace*{-10mm}
 Flux density in units of $10^{-14}$~erg~cm$^{-2}$~s$^{-1}$~$\AA^{-1}$.
\end{table}