\begin{table}%t1
      \caption{\label{modelparameters}IRAS~16293-2422 physical structure from dust modeling
         by Sch\"oier et~al.\ (\cite{schoieretal2002}).}
        %\centering
\par
         \begin{tabular}{ll}
            \hline\hline
            Parameter & Value \\ 
            \hline
     Distance, $d$ (pc) & 160 \\
     Luminosity, $L$ ($L_{\odot}$) & 27 \\
     Optical depth at $100$ ${\mu}$m, ${\tau_{100}}$ & 4.5 \\
     Density power law index, $p$ & 1.7 \\
     Inner envelope radius, $r_{\rm i}$ (cm) & $4.8 \times 10^{14}$ \\ 
     Outer envelope radius, $r_{\rm e}$ (cm) & $1.2 \times 10^{17}$ \\
     H$_{2}$ density at 1000 AU, $n_{0}$ (cm$^{-3}$) & $6.7 \times 10^{6}$ \\
                 \hline
     \end{tabular}
   \end{table}