Scientists pull air samples from skies to help people on land

The air gets a little thin at 25,000 feet above south-central Colorado, but that hasn't stopped Colorado State University atmospheric researcher Paul DeMott from taking to the skies for air samples.

DeMott has been studying how tiny particles form ice in clouds and the impact of changing atmospheric composition on clouds. Understanding where and how clouds and precipitation form ultimately can help scientists better predict droughts and major weather disasters that affect people throughout the world.

Special particles called ice nuclei, created from desert dusts, biological processes, and pollution, are needed to form ice in clouds. Scientists have spent decades trying to understand the processes. "If we can measure these particulates and how they make ice, can we predict exactly how ice will form in the ideal cloud?" DeMott said.

Air-bound researchers

DeMott was part of a select group of scientists flying out of Colorado's Rocky Mountain Metropolitan Airport in a specially equipped C-130 aircraft owned by the National Science Foundation and operated by the National Center for Atmospheric Research. CSU is the only university with the technology to take such continuous air samples from clouds and measure in real time the ice-forming ability of particles inside a plane.

As part of a National Science Foundation grant, CSU and other scientists temporarily retrofitted the C-130 with assessment equipment and often flew five hours a day from October through December to study clouds.

DeMott is the principal investigator on the three-year, $650,000 NSF grant obtained in 2006. On the research aircraft, he and his CSU team take air samples into a small chamber through a special port on the side of the plane.

A diffusion chamber cools and humidifies the air and particles – essentially allowing DeMott to "grow" clouds by simulating the conditions in the atmosphere. He then evaluates how many particles will form ice crystals for specific cloud conditions. The C-130 then passes through the wave clouds to measure how much ice really forms.

Last year, the grant took DeMott to Japan on trans-Pacific flights for another NSF study of how dust and pollution from Asia travel east to the United States and beyond.

Beyond Earth: Assessing the cancer risk of space travel

A Colorado State University researcher has answered President George W. Bush's 2004 space initiative. That initiative called for spending $12 billion on new space exploration during the next five years, developing a new manned exploration vehicle, launching manned missions to the moon between 2015 and 2020, and building a permanent lunar base as a stepping stone for more ambitious missions, including missions to the planet Mars.

Susan Bailey, associate professor in the Department of Environmental and Radiological Health Sciences, is researching the human factors of space travel, aiming to improve models of cancer risk for astronauts as they spend more time in space.

"Longer missions in space seem inevitable, but we don't fully understand the risks of galactic cosmic ray exposure to astronauts over extended periods of time," said Bailey, the recipient of the 2007 Michael Fry Research Award, which recognizes the contributions of a junior investigator to the field of radiation research.

NASA grant

Bailey began work in January on a new NASA grant investigating the role of telomeric proteins in the damage response to various types of radiation exposure. The physical ends of chromosomes, or telomeres, first described almost 70 years ago, consist of highly repetitive DNA that serve to maintain chromosomal stability by protecting the ends of chromosomes from degradation and preventing them from improperly fusing.

"Part of our work at Colorado State University is to enlighten greater understanding of those risks – of developing cancer later in life for example – so that NASA can make more informed decisions regarding acceptable risk levels as well as look for new avenues of risk mediation," said Bailey.

The unknown

"There remain many unknowns in space travel, some of which revolve around the questions we don't know the answers to in radiation biology," said Bailey.

NASA is helping CSU and other laboratories conduct critical basic research that is especially relevant to improved models of cancer risk for astronauts as they spend more time in space.

"Because radiation also affects people in their everyday lives, we all need to better understand the risks as well as the benefits," said Bailey. "The future of this Department as we further explore these questions is truly an exciting one and I am very proud to be a part of that."

Story is excerpted from the Colorado State University ERHS Emitter, Fall 2007.