Galway’s Captain A has shared his second new track of the summer, ‘Dark Matter Mariner’. The shadowy instrumental, as eerie and vast as its title suggests, follows July’s ‘Meaning Obscure’, and finds Captain A continuing his ventures away from psych rock and gnarled folk into the world of electronic music. Where 2019’s ‘Dog In The Woods’ was tender and inward-looking, ‘Dark Matter Mariner’ confronts much loftier subject matter, but with a similarly poignant sense of isolation. “It is the soundtrack to the first voyages made by humans into the realms of dark matter and dark energy,” he explains. Drifting, muffled…