\begin{table}%t3
   %\centering
\par
      \caption{\label{fluxes}X-ray fluxes of 51~Peg with 1$\sigma$ errors, calculated with WebPIMMS using a 1~MK thermal plasma model.}
\begin{tabular}{l l l}
    \hline\hline
    Instrument &  Flux (0.1--1.0~keV) & $\log L_{\rm X}$ (0.1--1.0~keV)  \\
	  & (erg s$^{-1}$ cm$^{-2}$) & (erg s$^{-1}$)\\ 
	  \hline\\[-3.2mm] 
    {\it XMM} PN & $1.2^{+1.0}_{-0.5}\times10^{-14}$ & 26.3--26.8\\[-3mm] \\ 
    {\it XMM} MOS1+2 &   $1.1^{+1.4}_{-0.6}\times10^{-14}$ & 26.1--26.8\\[-3mm] \\ 
    {\it Chandra} ACIS-S &  $1.7^{+0.9}_{-0.4}\times10^{-14}$  & 26.5--26.8\\[-3mm] \\ 
    {\it Chandra} HRC-I & $4.2^{+1.1}_{-0.7}\times10^{-14}$  & 27.0--27.2\\[-3mm] \\ 
    {\it ROSAT} PSPC & $2.1^{+0.3}_{-0.3}\times10^{-14}$  & 26.7--26.8\\[-3mm] \\
    \hline
    \end{tabular}
   \end{table}