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Plants Need CO2 To Grow
Former NASA Scientists and Astronauts Blast Agency for Disregarding Climate Change Evidence
April 10, 2012

Washington, D.C.-Nearly 50 former NASA scientists and astronauts-including seven Apollo astronauts and two former directors of NASA's Johnson Space Center in Houston-are condemning NASA for the space agency's role in advocating that man-made carbon dioxide (CO2) is a major cause of climate change while ignoring compelling empirical evidence that calls the theory into question. 

In a formal letter sent to NASA Administrator Charles Bolden, the group criticizes NASA, and specifically the Goddard Institute for Space Studies (GISS), for its failure to make an objective assessment of all available scientific data on climate change.  The scientists and astronauts argue that NASA is relying too heavily on complex climate models that have proven scientifically deficient in predicting climate change. 

"These American heroes-the astronauts that took to space and the scientists and engineers that put them there-are right to criticize NASA's advocacy of an extreme and unsubstantiated position," said Leighton Steward, chairman of Plants Need CO2.  Leighton Steward, a scientist, environmentalist, and New York Times best-selling author, had made presentations to many of the signatories of the letter and encouraged several in the group to come forward to make their concerns known to NASA.

"It's beyond disturbing that NASA would endanger its reputation and risk misleading the public by engaging in aggressive advocacy of scientifically unverified positions," said Leighton Steward.  "NASA has a duty to make an objective assessment of all the available scientific data on climate change-including empirical evidence that calls the theory of man-made global warming into question."

The formal letter reads in part:

  • "We believe the claims by NASA and GISS, that man-made carbon dioxide is having a catastrophic impact on global climate change are not substantiated, especially when considering thousands of years of empirical data."
  • "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."
  •  "As former NASA employees, we feel that NASA's advocacy of an extreme position, prior to a thorough study of the possible overwhelming impact of natural climate drivers is inappropriate. We request that NASA refrain from including unproven and unsupported remarks in its future releases and websites on this subject."

Plants Need CO2 is a national organization dedicated to educating the public on the positive effects of additional atmospheric CO2 and helping prevent the inadvertent negative impact to human, plant, and animal life of CO2 reductions.  Leighton Steward is a geologist, environmentalist, retired energy executive, and New York Times best-selling author.  In recognition of his many environmental efforts, Leighton Steward has received numerous awards including the regional EPA Administrator's Award for environmental excellence.  He is Chairman of the Board of the Institute for the Study of Earth and Man at SMU and was twice Chairman of the Audubon Nature Institute.

For more information or to arrange an interview with Leighton Steward, contact Stephen Manfredi at
(202) 222-8028 or

** For additional peer-reviewed scientific references and an in-depth discussion of the science supporting our position, please visit Climate Change Reconsidered: The Report of the Nongovernmental Planel on Climate Change (, or CO2 Science (