There are auspicious debuts, and then there’s a first effort like Bright Size Life, on which Pat Metheny opened the door to a vast musical universe that he’s still exploring today. Then just 22, the guitarist led a plugged-in trio — featuring drummer Bob Moses and a bassist on the cusp of superstardom named Jaco Pastorius — but the flashiness of fusion was nowhere to be found here. In its place was an airy, expansive sound, filled with wonder and open-hearted emotion. Paired with evocations of Metheny’s Heartland upbringing, the tracks bounded ahead with Ornette Coleman–like glee (“Missouri Uncompromised”) or unspooled with quiet yearning (“Unity Village”) and, as on the immortal title track, seemed to create a new jazz pastoralism for the high-flying ‘70s, sophisticated yet deeply rooted in the soil.