Almost exactly a quarter century ago, a strange thing happened on Mars, something unprecedented in its four-billion-year history. The thin skies above the Red Planet were pierced by hardware from another world. In July, 1976, NASA's Viking landers settled onto Mars' rusty surface - and carried with them the remote eyes of Earthlings.

For centuries, astronomers had speculated about the possibility of life on Mars. Some, squinting through small telescopes, claimed to see evidence of sophisticated civilizations. But the Viking landers were something else: they were the first efforts to find Martian biology by actually sending hardware to the Red Planet. The Viking mission put sophisticated, robotic experimental laboratories onto the Martian surface.

The man who headed up this landmark space mission was Harold P. ("Chuck") Klein.

Chuck Klein, whose nickname came from a popular baseball player of his youth, has been in the forefront of what is now called astrobiology since the 1960s. For decades he was a driving force at the SETI Institute, encouraging and participating in research into the possibilities of life beyond Earth.

Klein died on July 15. A description of his impressive achievements follows.

"We have lost a good old friend and the Father of Exobiology as well," Dr. John Billingham sadly remarked upon hearing of the death of Dr. Harold P. Klein. "He was one of the smartest people I ever met, and I learned much from him." Known as "Chuck" or "Hal" by his many friends and colleagues, Dr. Klein passed away quietly at his home the morning of July 15, 2001, after battling cancer for the past several months.

Billingham's sentiments echo those heard up and down the halls of NASA Ames Research Center and the SETI Institute, where Klein spent the last 40 years of his career. A specialist in microbial physiology, Klein received a B.A. in chemistry from Brooklyn College (1942) and a Ph.D. in bacteriology from the University of California (1950). Klein joined Ames in 1963, following seven years as Professor and Chairman of the Biology Department at Brandeis University in Massachusetts. He also taught at the University of California at Berkeley, and at the University of Washington Medical School. Until his retirement from NASA in June of 1984, Klein was Director of Life Sciences at the Ames Research Center, where he was responsible for research and development activities ranging from the origin and distribution of life in the universe to biomedical research and aviation safety. He was Scientist-in-Residence at Santa Clara University from 1985 until 1995. The SETI Institute has been proud to have Dr. Klein on staff as a Senior Research Scientist and Principal Investigator for the past 15-plus years.

Klein's many achievements are best summarized in the citation honoring his induction into the NASA Ames Hall of Fame in January, 2000:

"Harold P. Klein championed Ames' leadership in exobiology and the life sciences. As Biology Team leader for the Viking Project, he helped conceive the Viking Lander. Klein pioneered new realms of scientific research and provided insights into questions about life in the universe. He was a forerunner in establishing Ames' reputation and leadership as the key NASA institution for the study of astrobiology.

"Klein led the Viking Biology Team that performed automated life detection experiments on Mars in 1976-77, and flew biological experiments on two Soviet cosmos space missions (1977 and 1979). He served on the U.S. Space Science Board of the National Academy of Sciences from 1985 until 1989 and chaired its Committee on Planetary Biology and Chemical Evolution. He also chaired the American Institute of Biological Sciences peer review panel for NASA's Exobiology program from 1985 until 1990. In 1990 he was selected as a US Participating Scientist on the Russian Mars '96 mission."

In 1977, Dr. Klein shared the Cleveland-Newcomb Award of the AAAS, and also received the NASA Medal for Exceptional Scientific Achievement. In 1981, he received the Distinguished Alumnus award from Brooklyn College, and the NASA Medal for Outstanding Leadership. In that year, he also received a Presidential Meritorious Service Award.

He was a member of several societies, including Phi Beta Kappa, the American Society of Biological Chemists, the International Society for the Study of the Origin of Life, and the International Academy of Astronautics.

Obviously, Chuck Klein's footprint was large, and he will be missed by many.

July 2001