Socks, underwear, radiosonde. After getting dressed, my first task is the morning weather sounding. Always before breakfast, often before exchanging a single word for the day, I’m in the balloon lab, preparing a small atmospheric instrument. Then waiting in the shop, leaning against a snowmobile and listening to the loud rush of helium. Performing a sequence of knots, assembling and making tight, small actions ritualized by practice and protocols. When finally the whole balloon string is together–the ponderous weather ballon, the bright orange parachute, the 100-foot reel of thin cord, and the little sounding instrument with its stubble of antennas and sensors–I carefully edge around the Cat 933 track loader and exit out the big shop door.

As many a disappointed child has discovered, a liberated balloon quickly rises out of reach. And a radiosonde ballon released on a calm day does the same, smoothly accelerating through an arc of sky. Even after ~180 balloons, it’s still transfixing. But amid gusting winds, and with the delicate payload dangling four feet below the balloon, it takes some concentration to get everything airborne and not dashed against the surface. The simple approach–holding onto the lowest point in the string then letting go–almost guarantees failure in the wind. Standing in the wind, holding the payload, the balloon is pulled down in the leeward direction, until the whole string is almost horizontal with the ground. When the payload is released, it just swings into the ground–ah!–and bounces downwind before the balloon begins to gain height.

Instead, it’s a combination of patience and speed that allows for launches in the wind. Patience, as one stands with their back to the wind, the balloon bucking and thrashing, judging the gusts, waiting for the brief lulls that come even in a steady blow. Then speed–in that perfect moment–releasing the balloon but running with the payload, downwind, giving the balloon an extra second to rise, then swinging the payload underneath, letting go, hoping.

Just managing the balloon outside can be a trick. Buffeted by the wind, a balloon can exert a surprising amount of force.  Expecting strong gusts as I prepared to launch two weeks ago, I stepped outside in a strong, low position, anchored against the wind.  But the moment that the wind touched the balloon, I was yanked over backwards, and ended up like a disabled beetle, clinging to the balloon as I tried to roll back upright.

In the coldest weeks of winter, latex balloons grow brittle, and, failing to expand with altitude, they burst too low.  This is a particular problem for the launch of the weekly ozonesonde, which uses a yet-larger balloon and which is required to reach the ozone layer for any science benefit. Aiming for higher burst heights despite the cold, we released several plastic balloons this winter–a spectacular and challenging task that rallied all hands on station. The thin material of the plastic ballon is similar to a grocery-store produce bag, and it demands total vigilance to avoid damage. Since the plastic balloons can’t stretch to accommodate the two-hundred-fold expansion of helium as they rise, they’re sized to full volume at burst height: an enormous balloon. When inflated for launch, the ballon is gangly and delicate, with the helium occupying just a small bubble at one end of the long balloon, and the payload attached 45 feet away at the other. The release is a coordinated effort: the whole system strung out along the axis of the wind. Buoyant with helium, the bulbous end is released, and the excess balloon material is lifted out of helpers’ hands as it passes over them. Then on the end, the tech holding the payload begins a mad dash, carrying the payload downwind until the entire system aligns vertically. It’s hard to believe that such a big object can just float away. The photo sequence, set behind the SOB exhaust plume, really tells the story: the coordinated run, the released payload hanging just above the surface, and someone’s radio, dropped in the snow.