IRAM&#039;s antennas are mounted on rails, combining their signals into the resolving power of a much larger &quot;virtual antenna.&quot; At maximum separation, they can resolve 0.5 arcseconds of sky at an observing wavelength of 1.3 mm (230 GHz), equal to the apparent size of an apple at a distance of 60 km, or about 37 miles. (Photo: IRAM/Rebus)