Signs of life from Antarctic lake buried under more than 2,000 feet of ice

American scientists drilled into a lake beneath the Ross Ice Shelf to search for life. Using a sterilized hot water drill, they penetrated the ice while preventing contamination. Pressure management allowed lake water to rise into the borehole. The lake was shallower than expected, filled with sediments. Samples revealed microbes that likely metabolize iron and sulfur using oxygen from melting ice.

What did scientists retrieve from the lake on January 28, and what was notable about the water sample?

How do the microbes found in the water sample likely obtain energy?