DailyTech recently reported on a project underway by the European Space Agency to study the effects of radiation on astronauts who may be in space for prolonged periods of time. The ion beam generator at GSI promises the ability to study such effects on delicate tissues.

A research group at Georgetown University's Lombardi Comprehensive Cancer Center agrees with the dangers that interplanetary and future interstellar travel may pose to space-faring men and women. Experiments performed on mice with high-LET, or linear energy transfer radiation, similar to the kind of radiation astronauts may experience, has shown increased risk factors for cancers and premature aging.

The tests showed that exposure to high-LET radiation causes concentrated amounts of free radicals in mice gastrointestinal tracts, as well as an elevated level of stress response gene expression. Free radicals cause an oxidative environment, which can often lead to the formation of cancerous cells.

Also observed in the study was a premature aging affect on the animals. The exposed mice's fur turned grey much earlier in their life than normal. The research group intends to conduct MRI brain scans to determine if there were other aging affects caused by the radiation exposure.

High-LET radiation can be composed of several things including gamma radiation, high-energy protons, and charged iron particles. Solar flares contain high amounts of high-LET radiation. Space travelers will be subject to this and other types of radiation constantly and from all directions.

The dangerous difference between human-employed radiation, such as that of medical imaging and radiotherapies, which is considered low-LET, and space-dwelling radiation is its effect on tissues. While low-LET radiation has a low impact diffuse effect, high-LET emissions cause damage to localized areas.

One thing both studies agree on is the need for more data on the dangers of space travel to humans. The more scientists understand about these dangers, the safer space travel will become. Engineers will design safer craft while medical scientists develop means to combat radiation exposure. Perhaps with something as simple as an anti-radiation pill supplement, Mars-bound men and women will weather the long voyage with less duress and return safely and healthily to Earth.