An hour and forty minutes later, after first eating, donning pressure suits and traversing the treacherous descent, Tom and Sally finally attained the crater floor, near the now deceased and mangled rover. They took the next half hour rolling out the sounding gear and testing the apparatus, which appeared to be in good working order. To achieve feedback for the soundings, Tom swung the sledgehammer and struck the terrain several times with great force, each blow causing a small shock wave to ripple downward through the surface. The sensors positioned along the gear’s two cables transmitted data back to the nearby computer being monitored by Sally. As the cables cross in the middle at a 90° angle, this process rendered a three-dimensional view of the subsurface, extending down to a depth of nearly 100 meters.
“Tom! This is amazing! Come take a look at this!” Sally was very excited after viewing the results. In the Martian gravity of 0.38 of Earth’s, Tom took a few quick steps as he started moving toward her. He found himself approaching Sally so rapidly that he nearly fell over her, while clumsily trying to come to a halt in the somewhat bulky space suit.
“What is it?” he queried, anxiously.
“Look at the monitor!” she replied in an unusually high pitch. Tom squinted at the screen for a few moments, then drew back glancing over at Sally.
“Is that really what it appears to be? Can it be what I think it is?” he asked in astonishment.
Sally adjusted the output on the front of the display box, “Are you not seeing what I’m seeing?” she questioned.
“I sure as hell hope so!” he answered, savoring the sight. “Surface looks solid, down about thirty-five meters, then there’s about a five meter void above what looks like, HOLY SHIT, WATER! And it’s… forty meters down to the pool. From there the depth goes… BELOW THE SOUNDINGS!!” Tom hollered loudly in his elation. “That would put it more than sixty meters in depth! Let’s see… that’s 100 x 100 x 60 plus… that’s a fuckin’ lot of water! Plus, we’re just on the edge of the crater! This thing must be… what did we figure, eleven and a half kilometers across? Hey! We’re sitting on top of a volcanic caldera with a huge subsurface lake!” he finished, with a final fist pump in the air.