\begin{table}%t2
\caption{\label{yorp}Period changes due to YORP for selected asteroids.
$a$ is the orbital  semimajor axis and $D$ denotes the effective
diameter. }
%\centerline
 {\small \begin{tabular}{l l l l l l l}
\hline \hline\noalign{\smallskip}
Asteroid        & $a$  & $D$ & $P$        &$\sigma_{P}$ &     $\dot{P}$      & $\langle \dot{P} \rangle$ \\  
& [AU] & [km]& [h]        &$10^{-6}$~[h]&$10^{-6}$~[h/yr]      & $10^{-6}$~[h/yr] \\
\hline
(1620) Geographos & 1.2  &2.5 & 5.223336   &    2        &     $-0.75$          & $\pm$0.3  \\  
(1862) Apollo     & 1.5  &1.4 & 3.065447   &    3        &     $-1.2$           & $\pm$0.2  \\
(3103) Eger       & 1.4  &2.5 & 5.710150   &    6        &     $-0.7$           & $\pm$0.3  \\      
(54509) YORP      & 1.0  &0.1 & 0.20290046 &  0.01       &     $-0.3$           & $\pm$0.4  \\
\hline
2007 DD         & 1.0  &0.02& 0.07429    &   70        &--       & $\pm$1    \\
1998 KY$_{26}$  & 1.2  &0.03& 0.1783583  &    7        &  --         & $\pm$2    \\  
2006 XY         & 1.5  &0.05& 0.0829783  &  0.3        &  --          & $\pm$0.1  \\
&      &    & 0.0831226  &  0.4        &       --            &            \\
2000 HB$_{24}$  & 0.8  &0.05& 0.2176     &  600        &  --       & $\pm$3   \\
2000 YA         & 2.4  &0.06& 0.6658     &  100        & --      & $\pm$2    \\
2001 AV$_{43}$  & 1.3  &0.03& 0.1701     &  500        &   --        & $\pm$2    \\
2001 SQ$_{3}$   & 1.1  &0.14& 0.06248    &   50        &       --           & $\pm$0.02 \\
\hline
\end{tabular}}
\medskip
For the first four objects $P$ is the sidereal period of rotation, while for the rest it is a synodic one. $\sigma_{P}$ is a standard deviation of $P$, $\dot{P}$ is the observed rate of change of~$P$, while $\langle \dot{P} \rangle$ is a theoretically predicted,  approximate rate of change of~$P$.
\end{table}