Mechanical Engineering, Florida Atlantic University Christopher P. McKay (born 1954)[1] is an American planetary scientist at NASA Ames Research Center, studying planetary atmospheres, astrobiology, and terraforming.

He also performed field research on extremophiles, in such locations as Death Valley, the Atacama Desert,[10] Axel Heiberg Island, and ice-covered lakes in Antarctica.

McKay is the Principal Investigator of the proposed Icebreaker Life astrobiology mission to Mars.

[15] McKay advocates a moderately biocentric position in the ethics of terraforming, arguing that we must thoroughly explore a planet such as Mars first to discover whether there is any microbial life before taking first steps toward terraforming, and that if indigenous alien life is found in an obscure niche or dormant on Mars, we should remove all Earth life and alter Mars to support the global spread of this alien life on Mars.

[16][17] He has held a series of public debates with Robert Zubrin, who advocates a moderately anthropocentric position on the ethics of terraforming.