A minimal space interferometer configuration for imaging at low radio frequencies

The radio sky at lower frequencies, particularly below 20 MHz, is expected to be a combination of increasingly bright non-thermal emission and significant absorption from intervening thermal plasma. maps these frequencies cannot therefore obtained by simple extrapolation those higher frequencies. However, due severe constraints in ground-based observations, this spectral window still remains greatly unexplored. In paper, we propose study, through simulations, novel minimal configuration for space interferometer system which would enable imaging the well MHz with angular resolutions comparable achieved observations using aperture-synthesis technique. consists three apertures aboard Low Earth Orbit (LEO) satellites orbiting mutually orthogonal orbits. Orbital periods are deliberately chosen differ each other so as obtain maximum (u, v) coverage short time spans baselines greater than 15000 km, thus, giving us finer 10 arcsec even low sensitivity assessed varying orbit initial phase satellites. We discuss results simulations highlight advantages such system.