September 29th, 2009
Cosmic-Ray Intensity Hits 50-Year High
Planning a trip to Mars? Take plenty of shielding. According to sensors on NASA's ACE (Advanced Composition Explorer) spacecraft, galactic cosmic rays have just hit a space-age high.
"In 2009, cosmic ray intensities have increased 19% beyond anything we've seen in the past 50 years," says Richard Mewaldt of Caltech. "The increase is significant, and it could mean we need to re-think how much radiation shielding astronauts take with them on deep-space missions."
Filed under: Astronomy, Solar System | 8 Comments »
![Schematic showing the stream of charged hydrogen ions carried from the Sun by the solar wind. One possible scenario to explain hydration of the lunar surface is that during the daytime, when the Moon is exposed to the solar wind, hydrogen ions liberate oxygen from lunar minerals to form OH and H2O, which are then weakly held to the surface. At high temperatures (red-yellow) more molecules are released than adsorbed. When the temperature decreases (green-blue) OH and H2O accumulate. [Image courtesy of University of Maryland/F. Merlin/McREL]](https://web.archive.org/web/20091007055402im_/http://www.universetoday.com/wp-content/uploads/2009/09/water-on-the-moon.jpg "Schematic showing the stream of charged hydrogen ions carried from the Sun by the solar wind. One possible scenario to explain hydration of the lunar surface is that during the daytime, when the Moon is exposed to the solar wind, hydrogen ions liberate oxygen from lunar minerals to form OH and H2O, which are then weakly held to the surface. At high temperatures (red-yellow) more molecules are released than adsorbed. When the temperature decreases (green-blue) OH and H2O accumulate. [Image courtesy of University of Maryland/F. Merlin/McREL]")
