Werner Herzog’s five-year renaissance through man-versus-nature documentaries has trained one to expect Sturm und Drang mysticism and directorial harangues at the first mention of a high-stakes expedition. So Paul Devlin’s Blast!, about a balloon-mounted telescope, is initially something of a relief: Despite the gee-whiz appeal of the NASA-aided launches, the possibility of failure is allowed to be sobering, even mundane, like the moment when the project leader’s kid back home leaves Dad hanging on the phone. In Sweden and then McMurdo Station, Antarctica, Paul’s sturdy astrophysicist brother, Mark, spearheads two disaster-prone missions to suss out light from old galaxies, working with an endearingly frumpy colleague, grad-student minions, and launch-pad roadies. But while the portrayal of collaboration is respectable, and the balloon enchanting as it shimmers skyward, jellyfish-like, the doc is too flat for its own good. Previously broadcast, it has the circumscribed horizons and uniform momentum of a TV doc. The human element—Mark’s family, the God question—never quite gets its hooks in, partly because the scientists feel a bit camera-conscious, their chosen comments tidily entertaining. The interludes of scientific background are clear and concise, but the anticlimax of a six-year data-gathering project may come across a little too acutely.