\begin{table}%t1
\caption{\label{tab1}Studied spectra of  Jovian decametric emission.}
%\centering
\small
\begin{tabular}{cccc}
\hline\hline
&&& \\[-8pt]
Date  & Start time, UT  &  Duration & $f$  \\
$[$yyyy/mm/dd$]$ & [hh: mm: ss] & [s] & [MHz]  \\
\hline
2002/08/02 & 08:45:01 & 58.59  & 17.3--29.8 \\
2002/08/02 & 09:00:01 & 58.59  & 17.3--29.8 \\
2002/08/02 & 09:30:01 & 59.148  &  17.3--29.8  \\
2002/08/02 & 09:45:01 & 58.59  & 17.3--29.8 \\
2002/08/02 & 10:15:02 & 58.59  & 17.3--29.8 \\
2002/08/09 & 10:30:01 & 59.706 & 17.3--29.8 \\
2002/08/09 & 10:45:01 & 59.706 & 17.3--29.8 \\
2002/08/09 & 11:00:01 & 59.706 & 17.3--29.8 \\
2002/08/09 & 11:15:01 & 60.264 & 17.3--29.8 \\
2002/08/09 & 11:30:01 & 60.822 & 17.3--29.8 \\
2000/03/30 & 11:44:52 & 50.406 & 15.3--27.8 \\
2000/03/30 & 12:00:04 & 41.54 &  15.3--27.8  \\
2000/03/30 & 12:14:52 & 16.492 &  15.3--27.8  \\
2000/03/30 & 12:15:14 & 9.486 & 17.3--29.8  \\
\hline
\end{tabular}
\end{table}