This is part six of the Anton deGama story, Black Ice. Anton's crawler is sliding towards a deep trench on Titan. Anton has a cunning plan...
He could not stop the ice boulder sliding, that was clear. But a judicious push might just alter its course, and perhaps even its speed. Of course, pushing a hundred-tonne block of ice would not be that easy. This chunk was already just ahead of the crawler. He crawled warily to the left side of the ice, and used the laser to melt a hole in the lower edge. He leaned down, and shoved the cylinder into the ice, before gingerly opening the valve. A jet of pure oxygen tore out from the side of the boulder, turning the methane atmosphere into a highly explosive cocktail.
Anton ran back towards the crawler, and leaped with a little more grace back onto the walkway. The drop-off could be only seconds away: he had no time to judge it carefully. He aimed the laser, hung on tightly, and shot directly at the oxygen stream.
The atmosphere detonated in an orange flower of blazing methane.
As always, comments welcomed!