\begin{table}%t3
\caption {\label{tab3}{Abundances of Bennu vs. solar$^{{a}}$.}}
%\centerline
 {\begin{tabular}{lcccc}
\hline\hline
Element & \de~=~500 & =3700  & Model  & Sun \\
\hline
He/H                  & .125(20) & .125(20) & .108(10) & .098 \\
O/H~$\times$~10$^{4}$ & 1.18(14) & 1.21(17) & 1.7(13)  & 4.9 \\
N/O~$\times$~10       & 3.4(24)  & 2.3(26)  & 1.5(15)  & 1.6 \\
Ne/O~$\times$~10      & 2.0(30)  & 2.0(26)  & 1.4(15)  & 1.8 \\
S/O~$\times$~10$^{3}$ & 6.5(50)  & 6.5(50)  & 10.$^{{b}}$ & 37. \\
Ar/O~$\times$~10$^{3}$  & 2.4(30)  & 2.2(30)  & 2.3(25)  & 8.5 \\
\hline
\end{tabular}}
\par
\smallskip
\par
 { {$^{{a}}$}  Proto-solar abundances from Asplund et~al. (\cite{asplund_etal05}), except for O/H from Allende-Prieto et~al.\
(\cite{allende}). Percentage errors in parenthesis. %\end{list}
}
\par
{{$^{{b}}$}  S/Ar solar; S/O~$\times$~10$^{3}$ may as well be 20
according to model outputs.
}
\par
\end{table}