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Anomalous Long Term Effects in Astronauts' Central Nervous System-GAP (ALTEA_GAP)
Principal Investigator
Research Area:
Radiation biology
Species Studied
Scientific Name: Homo sapiens Species: Human

Outside the protection of Earth's atmosphere, ISS crewmembers are exposed to increased radiation, but the radiation environment is even more severe as exploration crews leave Earth's geomagnetic field and transit to other planets. The measurements made by the ALTEA hardware will help scientists characterize the heavy ion radiation spectrum inside the ISS, and the measurements while the ISS is at high geomagnetic latitudes will give insight to the radiation environment outside the Earth's magnetosphere.

Long-duration space flights result in increased cosmic radiation exposure to astronauts. The ALTEA hardware is designed to measure particle radiation in the space environment, and determine how this radiation impacts the central nervous system (CNS) of the crew. Anomalous Long Term Effects in Astronauts' Central Nervous System - GAP (ALTEA-GAP) is comprised of a helmet-shaped device holding 6 silicon particle detectors designed to measure cosmic radiation passing through the brain. The detectors measure the trajectory, energy, and species of individual ionizing particles. At the same time an electroencephalograph (EEG) measures the brain activity of the crewmember to determine if radiation strikes cause changes in the electrophysiology of the brain in real time.

A common effect of radiation exposure that is reported by crewmembers is the perception of light flashes. The actual mechanism of these light flashes is not understood. Earlier studies on the Mir space station suggest that both heavy nuclei and protons trigger abnormal CNS responses. (Casolino et al. 2003). A Visual Stimulator tests the crewmember's overall visual system, including dark adaptation stimuli to monitor visual status. While not manned, the ALTEA hardware provides a continuous measure of the cosmic radiation in the ISS U.S. Laboratory, Destiny. The neurophysiological effects of cosmic radiation in long term space travel have never been explored with the depth of the ALTEA experiment. Data collected will help quantify risks to astronauts on future long-duration space missions and propose optimized countermeasures.

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Radiation monitoring

Data Information
Data Availability
Archive is complete. No data sets are available for this experiment. Please Contact LSDA if you know of available data for this investigation.

Radiation exposure
Radiation measurement

Mission/Study Information
Mission Launch/Start Date Landing/End Date Duration
Expedition 29 09/16/2011 11/21/2011 40 days
Expedition 30 11/14/2011 04/27/2012 166 days

Additional Information
Managing NASA Center
Johnson Space Center (JSC)
Responsible NASA Representative
Johnson Space Center LSDA Office
Project Manager: Pamela A. Bieri
Institutional Support
Italian Space Agency (ASI)
National Aeronautics and Space Administration (NASA)