Ben Taub, The New Yorker:

Past twenty-seven thousand feet, the pilot had gone beyond the theoretical limit for any kind of fish. (Their cells collapse at greater depths.) After thirty-five thousand feet, he began releasing a series of weights, to slow his descent. Nearly seven miles of water was pressing on the titanium sphere. If there were any imperfections, it could instantly implode.

And:

For the next hour, he explored the featureless beige sediment, and tried to find and collect a rock sample. Then the lights flickered, and an alarm went off. Vescovo checked his systems—there was a catastrophic failure in battery one. Water had seeped into the electronics, bringing about a less welcome superlative: the deepest-ever artificial explosion was taking place a few feet from his head.

If there were oxygen at that depth, there could have been a raging fire. Instead, a battery junction box melted, burning a hole through its external shell without ever showing a flame. Any instinct to panic was suppressed by the impossibility of rescue. Vescovo would have to come up on his own.

This was a riveting read, a ripping yarn.