5 Concluding remarks

Using the present data on redshifts for nearby galaxies we determined a more accurate center position and a boundary of the nearest void in Hercules-Aquila which has been found by Tully. Towards {RA = 18$^{\rm h}38^{\rm m}$, $D = +18\hbox{$^\circ$}$}, the Local Void occupies an area $60\hbox{$^\circ$}$ in diameter and extends to V₀= 1500 km s^-1. Our search for nearby dwarf galaxies made on the POSS-II films provided 78 objects, 22 of them being situated in the direction of the void. HI survey of these objects is in progress with the 100 m Effelsberg radio telescope.

The Hercules-Aquila Void is a perfect target for a search of very dwarfish (pygmy) galaxies, which may occurr in cosmic voids. This sky region looks to be very suitable for a systematic blind survey of dwarf irregular galaxies in HI down to $M_{\rm HI} = -13$ mag, as well as low-mass gas clouds.

Acknowledgements

We have made extensive use of the Lyon-Meudon Extragalactic Database (LEDA, supplied by the LEDA team at the CRAL-Observatoire de Lyon), the NASA/IPAC Extragalactic Database (NED, which is operated by the Jet Propulsion Laboratory, Caltech, under contract with the National Aeronautics and Space Administration), and the Digitized Sky Survey (DSS-1) produced at the Space Telescope Science Institute under U.S. Goverment grant NAG W-2166. Our project is supported by INTAS-RFBR grant 95-IN-RU-1390 and DFG grant KS 9112.