The Jupiter Collisions, Lachlan Mackinnon's third collection, opens with a characteristically exact account of something ungraspable: a distant episode in cosmology. This is the starting point for a series of investigations into uncertainty and flux, in which poem after poem brings home its cargo in precisely shaped but oblique and surprising ways. The collection is as various in its concerns as it is unified in its search for the close naming of things. One of the paradoxes of these poems is to start from spareness and reserve, and to end by establishing an intensely personal voice, whatever the subject almost casually to hand - American scenes, foreign places, the remembered present of the 1960s, the lives within paintings, the potentiality of prime numbers. The Jupiter Collisions includes two subtle and intriguingly constructed sequences of linked poems, in which the canvas of personal matter (loss, love, contingency) is stretched across a frame of philosophical concerns, in a poetry which is as unafraid of thinking - 'the heaven of ideas' - as it is firmly vested in 'the pointillisme of what is'. We come to recognise a tone, quietly distinctive, addressing the world in poems which are cool but numinous in their phrasing, moving in their understatement.