Protection from Coronal Mass Ejection
Date: Summer 2013
Is there a way to be alerted of a Coronal Mass Ejection (CME) before the particles moving at light-speed reach Earth? If not, then how would we defend against the slower, more deadly part of a CME that follows the faster part?
First off I would like to refer you to http://science.nasa.gov/ for the NASA News feed. This is a service of NASA that, among other things, warns of solar events affecting Earth's atmosphere. Often these take the form of aurora alerts.
Also, there are satellites that can provide an early warning of the slower mass of the CME, and sunspots that are possible sources of CMEs are detected as the sun rotates them in our direction, which takes several days or more.
Go to the NASA site which does a far better job of explaining things than I do.
Hope that helps.
Thanks for the question. Solar telescopes that look at the Sun are able to detect when a CME occurs. Since the speed of light is faster than the speed of the ejected particles, it is possible to warn people on Earth. The CME contains mostly positively charged ions. The most abundant of these ions are hydrogen ions, or protons. Most of the ions are stopped in the upper atmosphere when they interact with gaseous molecules and atoms. A very small percentage of ions actually reach the surface of Earth. The best way to shield yourself from these ions is to build a shield which uses a material with a high atomic number. The larger the atomic number, the better the material is for stopping these charged particles of the CME. Typical materials used are dirt/earth, concrete, water, and heavy metal.
I hope this helps.
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