You can take the purported extraterrestrial origins of the Sun Ra Arkestra as mere showmanship, or as sci-fi social commentary. But watching bandleader Marshall Allen on Thursday at the Ardmore Music Hall - eliciting trademark squawks and grunts from his alto saxophone and conducting the cacophony of the 14-piece band for more than two hours just days before his 91st birthday - you could start to believe that there is something not quite human about him.

Thursday's show was a double celebration, falling on the eve of what would have been longtime Philadelphian and founder Sun Ra's 101st birthday - or "Arrival Day," to use the Arkestra vernacular, marking his appearance in Birmingham, Ala., from his native Saturn.

Other than a brief mention of Allen's coming anniversary by longtime baritone saxophonist Danny Thompson, the show was business as (un)usual, though the inclusion of the jazz standard "Stars Fell on Alabama" in the set list may have been a sly nod to the departed leader.

The show was a typically sprawling and raucous affair. The band hardly had time to take the stage, their sequined, brightly colored caps and capes glimmering, before keyboardist Farid Barron launched into "Interplanetary Music." The first set also included the unruly Ellingtonia of "Sunology," with Barron evoking Sun Ra's Farfisa organ sound and Allen summoning clamor with the skyward thrust of his arm.

The evening, as always with the Arkestra, was wide-ranging and unpredictable. The conga-driven exotica of "Velvet" led into the aptly-named "Blue Set," featuring a fuzz-toned guitar solo by Dave Hotep and the gutbucket blues vocals of Tara Middleton, sporting blue lipstick and shades over a silver cape and gold tights.

The second set was even wilder, with Allen and Middleton chanting cosmic slogans during "Discipline 27-II," leading into a riotous group improv featuring the sampled voice of Sun Ra himself.

The Neal Hefti-"inspired" novelty "I'm Gonna Unmask the Batman" was followed by the off-kilter ballad "Interstellar Lo-Ways," and the band marched through the crowd to finish with "Fate in a Pleasant Mood."

Allen will continue celebrating this week by joining the improvising trio Spectral at the Art Alliance on Saturday and the Arkestra-inspired ensemble UB-313 at the Rotunda on Wednesday.

He shows no sign of flagging, conjuring ecstatic ululations from his alto and electronic swoops and spirals on the EWI (Electric Wind Instrument).