A sub-millimetre aperture synthesis array for nonsolar planet detection

Abstract

The detection of Earth-like planets orbiting other stars has great scientific interest, but is a challenging observational goal. At wavelengths shorter than 4 μm a terrestrial planet would be about 10¹⁰ times fainter than a solar-type star, and at a distance of 10 parsecs the planet–star separation would never exceed 0.1 arc-sec. At wavelengths longer than 50–100 μm the brightness ratio is reduced by four to five orders of magnitude. Here we consider the possibility of using aperture synthesis to image other planetary systems at sub-millimetre wavelengths (50–1,000 μm). This approach requires only a small increase in dynamic range over that already demonstrated by the Very Large Array at longer wavelengths.