text: An innovative use of the diamond anvil cell is testing the sustainability and durability of life under high pressures, including the search for life on extrasolar planets. Testing portions of the theory of panspermia (a form of interstellar travel) is one application of DAC. When interstellar objects containing life-forms impact a planetary body, there is high pressure upon impact and the DAC can replicate this pressure to determine if the organisms could survive. Another reason the DAC is applicable for testing life on extrasolar planets is that planetary bodies that hold the potential for life may have incredibly high pressure on their surface.
  In 2002, scientists at the Carnegie Institution of Washington examined the pressure limits of life processes. Suspensions of bacteria, specifically Escherichia coli and Shewanella oneidensis, were placed in the DAC, and the pressure was raised to 1.6 GPa, which is more than 16,000 times Earth's surface pressure (985 hPa). After 30 hours, only about 1% of the bacteria survived. The experimenters then added a dye to the solution. If the cells survived the squeezing and were capable of carrying out life processes, specifically breaking down formate, the dye would turn clear. 1.6 GPa is such great pressure that during the experiment the DAC turned the solution into ice-IV, a room-temperature ice. When the bacteria broke down the formate in the ice, liquid pockets would form because of the chemical reaction. The bacteria were also able to cling to the surface of the DAC with their tails.
  Skeptics debated whether breaking down formate is enough to consider the bacteria living. Art Yayanos, an oceanographer at the Scripps Institute of Oceanography in La Jolla, California, believes an organism should only be considered living if it can reproduce. Subsequent results from independent research groups have shown the validity of the 2002 work. This is a significant step that reiterates the need for a new approach to the old problem of studying environmental extremes through experiments. There is practically no debate whether microbial life can survive pressures up to 600 MPa, which has been shown over the last decade or so to be valid through a number of scattered publications.
  Similar tests were performed with a low-pressure (0.1–600 MPa) diamond anvil cell, which has better imaging quality and signal collection. The studied microbes, Saccharomyces cerevisiae (baker's yeast), continued to grow at pressures of 15–50 MPa, and died at 200 MPa.