Anomalous Long Term Effects in Astronauts' Central Nervous System-GAP (ALTEA-GAP) - 07.29.14
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Anomalous Long Term Effects in Astronauts' Central Nervous System-GAP (ALTEA-GAP ) operates in DOSI mode (unmanned) to provide an assessment of the radiation environment inside the International Space Station (ISS), U.S. Laboratory, Destiny.
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Alenia Spazio - Laben, Milano, , Italy
Italian Space Agency (ASI), Rome, , Italy
Sponsoring Space Agency
National Aeronautics and Space Administration (NASA)
Human Exploration and Operations Mission Directorate (HEOMD)
ISS Expedition Duration
September 2011 - May 2012
Previous ISS Missions
- Radiation exposure represents one of the greatest risks to humans traveling on exploration missions beyond low Earth orbit (LEO).
- Anomalous Long Term Effects in Astronauts' Central Nervous System-GAP (ALTEA-GAP) measures the particle flux in the U.S. Laboratory, Destiny on the International Space Station (ISS), discriminates particle type and measures particle trajectory and deposited energy.
- Comparison between data collected by ALTEA-GAP, Intravehicular Charged Particle Directional Spectrometer (IVCPDS), and Extravhicular Charged Particle Directional Spectrometer (EVCPDS) will aid space agencies in understanding the radiation spectrum and radiation shielding characteristics of the Destiny.
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.
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.
Previous research data provided from the ALTEA investigation can lead to further understanding of how radiation may affect brain function on Earth as well as in space. While the levels of heavy ion radiation are much higher in space than on Earth, any understanding into the way radiation may alter brain function is extremely useful to neuroscientists of these studies. Ion therapies to treat brain tumors will also benefit from the ALTEA results.
ALTEA-GAP obtains accurate measurements of the radiation environment inside the ISS to study the particle fluxes, in relation with the known fluxes outside the station. ALTEA-GAP does not require crew time after it is unstowed.
At the beginning of each ALTEA-GAP measurement the crewmember starts the automatic set-up/calibration procedure and the session. At the end the crewmember stops the measurement. During the measurement the data collected by the particle detectors needed to study energy, trajectory, and type of the cosmic particles is sent to Earth in real time via automated telemetry.