\begin{table}%t1
\caption{\label{tbl-1}Observation log.}
%\centering
\par
\begin{tabular}{ccccc}
\hline\hline
Observatory & Start UT date &  Time  & Object & $t_{\rm exp}$(s)   \\
\hline
APO  & 2006 Sep. 30&  03:11:01 & LP~400-22& 1800    \\
     &             &  03:42:22  & HeNeAr  & 90 \\
     &            &  03:45:05 & LP~400-22& 1800    \\
     &             &  04:16:20  & HeNeAr  & 180\\
     &            &  04:20:44 & LP~400-22& 1800    \\
     &            &  04:51:57 & LP~400-22& 1800    \\
     &             &  05:23:09  & HeNeAr  & 180\\
     &            &  05:28:07 & LP~400-22& 1800    \\
     &            &  05:59:00 & LP~400-22& 1800    \\
     &             &  06:30:12  & HeNeAr  & 180\\
KPNO & 2009 May 30 &  10:18:41  & LP~400-22&  1800    \\
     &             &  10:50:38  & HeNeAr  & 30 \\
     & 2009 May 31 &  09:56:28  & LP~400-22&  1800    \\
     &             &  10:28:23  & HeNeAr  & 30 \\
     & 2009 May 01 &  08:59:53  & LP~400-22&  1800    \\
     &             &  09:32:08  & HeNeAr  & 30 \\
     & 2009 May 02 &  09:51:10  & LP~400-22&  1800    \\
     &             &  10:22:29  & LP~400-22&  1800    \\
     &             &  10:55:07  & HeNeAr  & 30 \\
\hline
\end{tabular}
\end{table}