ADS 9731: A new sextuple system

Based on observations with the correlation radial-velocity meter, we have established that components A and D of the visual quadruple system ADS 9731 = HD 139691 are spectroscopic binaries with periods of 3.87 and 14.3 days, respectively. Their orbits are determined. Our photometry reveals no eclipses in the close pair Aab, whose components have subsynchronous axial rotation. We determine the spectral types and luminosities of the six components that match the observed colors and the magnitude differences and that correspond to a distance of 115 pc. An analysis of the relative motions and radial velocities confirms that this is a physical system with an age of about 10^9 years.