Group slams NASA over climate change stand WASHINGTON, April 11 (UPI) -- Some former NASA scientists and astronauts are criticizing the space agency for its support for the certainty of human-caused climate change. In a letter to NASA Administrator Charles Bolden, 49 NASA scientists and astronauts admonished the agency for advocating a high degree of certainty that man-made CO2 is a major cause of climate change while allegedly neglecting empirical evidence that calls the theory into question, The Science & Public Policy Institute blog reported. The group, including seven Apollo astronauts and two former directors of NASA's Johnson Space Center in Houston, charged NASA with relying too heavily on complex climate models that have proven scientifically inadequate in predicting climate only one or two decades in advance, and with failing to make an objective assessment of all available scientific data on climate change. "The unbridled advocacy of CO2 being the major cause of climate change is unbecoming of NASA's history of making an objective assessment of all available scientific data prior to making decisions or public statements," the group said in its letter. We request that NASA refrain from including unproven and unsupported remarks in its future releases and Web sites on this subject.