\begin{table}%t1
\caption{\label{data} Data of observations. }
%\centerline
{
\begin{tabular}{llccccrr}
\hline\hline \noalign{\smallskip}
\multicolumn{1}{c}{Orbit} & \multicolumn{1}{c}{Observing date} &
\multicolumn{1}{c}{PN mode} &
\multicolumn{1}{c}{Filter} & \multicolumn{1}{c}{On time} &
\multicolumn{1}{c}{}Live time & \multicolumn{1}{c}{count rate} &
\multicolumn{1}{c}{RGS} \\
\multicolumn{1}{c}{  } & \multicolumn{1}{c}{(UT)} &
\multicolumn{1}{c}{  } &
\multicolumn{1}{c}{ } & \multicolumn{1}{c}{s} &
\multicolumn{1}{c}{(s)} & \multicolumn{1}{c}{on chip} &
\multicolumn{1}{c}{count rate} \\
\noalign{\smallskip} \hline \noalign{\smallskip}
 084 & May 25, 2000: 03:53--10:11 & Tim & Thick &
   16279 & 16781 & 373.97 & $18.6\pm2.2$\\
 084 & May 25, 2000: 10:35--19:37 & SW & Thick &
   30203 & 21159 & 300.13 & n/a \\
 165 & Nov. 02, 2000: 00:10--10:25 & SW & Thick &
   34560  & 24242 & 133.78 & $6.4\pm1.3$\\
 171-1 & Nov. 13, 2000: 22:22--11:20$^{\dagger}$ & SW & Thick &
   36553 & 25640 & 384.59 & $18.5\pm2.1$ \\
 171-2$^{\clubsuit}$ & Nov. 14, 2000: 13:54--01:51$^{\dagger}$ & SW & Thick &
   33384 & 23417 & 372.85 & $20.6\pm2.2$\\
 259 & May 08, 2001: 09:10--19:59 & SW & Thin &
   36678 & 25727 & 407.42 & $14.0\pm1.9$ \\
 440-1$^{\clubsuit}$ & May 04, 2002: 16:49--03:03$^{\dagger}$ & LW & Thick &
  36715 & 34345 & 108.21 & $6.6\pm1.5$ \\
 440-2$^{\clubsuit}$ & May 05, 2002: 03:51--09:24 & LW & Thick &
 17059 & 15954 & 78.01  & n/a \\
\hline
\end{tabular}}
\smallskip
\hspace*{1.7cm}$^{\dagger}$: Next day. \\
\hspace*{1.7cm}$^{\clubsuit}$: Source in off-set position. \\
\end{table}