Even in this time of 7 billion human inhabitants, there are
still frontiers being explored on Earth. One frontier is Earth’s
deepest depths, which scientists are probing for signs of life.
In late 2010, microbiologist Stephen Giovannoni and his research
team discovered bacterial life deeper in the Earth’s crust than
ever before, 1.4 kilometers below the sea floor in the North
Atlantic. This discovery might have implications for life on
other planets, such as Mars. For four months, a research ship,
part of the Integrated Ocean Drilling Program, drilled down into
the rock below the ocean floor to the deepest layer of Earth’s
crust. Rock samples from the drill cores revealed living
organisms. Giovannoni said: This expedition investigated
microbial life in gabbros, which are rocks in the deep part of
the ocean crust, and discovered bacteria there. How can
bacteria, or any form of life, survive in rock so deep
underground? Dr. Giovannoni explained that cracks in the ocean
floor allow seawater and microbes to circu