There was another scientist involved with exobiology research in Antartica who died in a tragic accident, Wolf Vishniac:

On Mars: Exploration of the Red Planet. 1958-1978.
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SCIENTISTS, INSTRUMENTS, AND SUBCONTRACTORS.
"In 1973, Vishniac was still pursuing his research into the origins of life and the possibility of life on other worlds when he fell 150 meters to his death in Antarctica's Asgard Mountains. Searching for life in the dry valleys of that bitter cold and windswept region, Vishniac was attempting to prove that life forms could adapt to extremely hostile environments. Early in 1972, he had found microorganisms growing in what had previously been thought to be sterile dry valleys. This discovery by Vishniac and his graduate student assistant Stanley E. Mainzer, using a version of the Wolf Trap light-scattering instrument, was a bit of good news for the believers in life on other planets but a contradiction of the findings of Norman Horowitz and his colleagues Roy E. Cameron and Jerry S. Hubbard, who in five years of research had yet to detect any life forms in that barren land. "
http://www.hq.nasa.gov/office/pao/History/SP-4212/ch7-4.html

I believe Carl Sagan said of Vishniac he was the second scientist after Giordano Bruno to die furthering the idea of extraterrestrial life.

It is interesting that Visniac's device was able to detect microbes in this environment where other methods did not. Vishniac's experiment had to be cut from Viking because of cost over-runs on the project. Ironically his might have been the only one with the sensitivity to detect microbes at the level of Gil Levin's experiment.

Vishniac's detection of microbes in this harsh environment has recently been confirmed:

Thursday, 17 January, 2002, 20:09 GMT
Alien life could be like Antarctic bugs
http://news.bbc.co.uk/hi/english/sci/tech/newsid_1765000/1765792.stm

Morphogenesis of Antarctic Paleosols: Martian Analogue.
Icarus,Vol. 154, No. 1, November 1, 2001
http://www.idealibrary.com/servlet/citation/0019-1035/154/113 [abstract]

Other research has likewise found life and liquid water at below zero temperatures in Siberian permafrost:

Metabolic Activity of Permafrost Bacteria below the Freezing Point.
Applied and Environmental Microbiology, August 2000,p.3230-3233,Vol.66, No.8
http://aem.asm.org/cgi/content/full/66/8/3230 [full text]