\begin{table}%t8
\par
  \caption {\label{tableQ}Comparison of Orcus and Quaoar additional parameters.  }                  
%\centering
$$
\begin{tabular}{clll}  
  \hline 
\hline    
\noalign{\smallskip}
  & \textbf{Parameter} & \textbf{Orcus} & \textbf{Quaoar}\\ 
  \hline 
  \multirow{4}*{\rotatebox{90}{Orbit}}
  & Dynamical class                     & Plutino                             & Classical KBO                \\ 
  & Semi-major axis$^{1}$ (AU)          & 39.163                              & 43.467                       \\
  & Eccentricity$^{1}$                  & 0.227                               & 0.040                         \\
  & $P$ (yr)                           & 245.5                               & 286.9                         \\ 
\hline
  \multirow{5}*{\rotatebox{90}{Phys. prop.}}
  & \multirow{2}*{Density (g~cm$^{-1}$)} & 1.9~$\pm$~0.4$^{a}$                    & \multirow{2}*{$>$2.8$^{c}$}        \\
  &                                    & 1.5~$\pm$~0.3$^{b}$                    &                                               \\
\cline{2-4}
  & $T_{\rm surf}$ max. (K) & 40--50 & 42--46 \\
\cline{2-4} \\[-3.5mm]
    & \multirow{2}*{Insulation per orb. (J)}   & \multirow{2}*{$\sim$2.0~$\times$~10$^{21}$}   & 1.5~$\times$~10$^{21}$ \\
  &                                    &                                       & 3.3~$\times$~10$^{21}$ \\ 
  \hline 
  \multirow{2}*{\rotatebox{90}{Sat.}}
  & Brightness                         & \multirow{2}*{8$^{a}$}              & \multirow{2}*{0.6$^{a}$}\\
  &fraction (\%)&&\\
  \hline
\end{tabular}
$$
\tablebib{1: values from the Minor Planet Center. a: \cite{Brown08}; b: \cite{Brown+10}; c: \cite{Fraser+09}.}
\end{table}