Earth's oldest biosphere still draws interest

What does Dale Andersen, a senior scientist at the Carl Sagan Center within the SETI Institute whose research concentrates on microbial environments of the Artic, Antarctic, Abacama Desert, Death Valley and Siberia, have in common with Zena Cardman, who grew up in Williamsburg and is a Bruton High grad, selected as an U.S. astronaut candidate?

It turns out, quite a lot.

Andersen wrote to me: "You may have heard that NASA selected their most recent class of astronaut candidates and Zena Cardman is among those selected. She is a friend of mine and my family. I first met her at Pavilion Lake in British Columbia in 2008 when she joined us as an undergrad. We worked there together over the next seven years or so which gave us the opportunity to see Zena progress academically from an undergrad to a grad student, getting her bachelor's degree in Biology and master's degree in Marine Science at UNC Chapel Hill, then on to Penn State to pursue her doctorate. She will have to delay the doctorate now that she has the 'new job' of being an astronaut.

"But knowing Zena, she will find a way to finish it off while becoming an astronaut, or perhaps on the way to the Moon or Mars! She is a great person and a delight to get to know over the years."

Cardman, now 29 years old, was one of a dozen people selected out of more than 18,000 applicants for the astronaut program. Among the many experiences that enhanced her chances to be selected was her research with American and Canadian astrobiologists and astronauts in a wide array of environments including on the Arctic, Antarctica and at Pavilion Lake.

As Cardman is starting her two-year training at NASA's Johnson Space Center, in Houston. It will include learning to fly T38 jets, to speak Russian, how to spacewalk and work at the International Space Station. Andersen is just completing work with NHK, the Japanese Broadcasting Corporation on a major 8K documentary about his work in Antarctica.

Reflecting on the Japanese documentary, Andersen said: "The basic story is that the ice-covered lakes in Antarctica provide a window back in time allowing us to gain insight about Earth's early biosphere, one dominated by single-celled microbes, cyanobacteria. The lakes we study have no larger organism like fish, insects or other major invertebrates so they are great analogs for those Precambrian ecosystems."

He noted, that preserved in ancient sediments of the Pilbara region of Western Australia are some of the oldest evidence of life on the Earth including large, conical stromatolites dating back to about 3.45 billion years ago.

"There are modern large, conical stromatolites forming in Lake Untersee today and we wanted to document what are essentially their ancient relatives in Pilbara," Andersen commented.

The results of Andersen's research triggered a series of articles in scientific journals.

ScienceNews wrote, "In the eerie bluish-purple depth of an Antarctic Lake, scientists have discovered otherworldly mounds that tell tales of the planet's early days.... It is like going back to early Earth."

Andersen is one of only seven people who have explored the depth of Lake Untersee in Antarctica by diving through a hole cut through 10 feet of ice. From there he faced 500 feet of bleakness below. He has dived into many more such polar lakes in search of primitive life forms. He was quoted saying: "These are just incredibly beautiful microbial landscapes. The discovery of the stromatolites rocketed East Antarctica's Lake Untersee to the top of my list."

Shatz, a Williamsburg resident is the author of "Reports from a Distant Place," a compilation of his selected columns. The book is available at the Bruton Parihs Shop and

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