Have you ever been hit by a beam of high energy particles from above? Surely you have -- it happens all of the time. Showers of high energy particles occur when energetic cosmic rays [
http://www.srl.calt… cos_encyc.html ] strike the top of the Earth's atmosphere. Cosmic rays were discovered unexpectedly [
http://helios.gsfc.… hist_1900.html ] in 1912. It is now known that most cosmic rays are atomic nuclei [
http://en.wikipedia… ]. Most are hydrogen [
http://periodic.lan… ] nuclei, some are helium [
http://periodic.lan… ] nuclei, and the rest heavier elements. The relative abundance changes with cosmic ray energy -- the highest energy cosmic rays tend to be heavier nuclei. Although many of the low energy cosmic rays [
http://en.wikipedia… ] come from our Sun, the origins of the highest energy cosmic rays remains unknown and a topic of much research. This drawing [
http://universe.nas… images-library4.html ] illustrates air showers [
http://www.mpi-hd.m… ] from very high energy cosmic rays [
http://helios.gsfc.… ]. Cosmic rays [
http://www.auger.or… ] may even be important [
http://www.fnal.gov… ] to Earth's weather -- common lightning [
http://antwrp.gsfc.… ] may be triggered by passing cosmic rays.
explanation
Have you ever been hit by a beam of high energy particles from above? Surely you have -- it happens all of the time. Showers of high energy particles occur when energetic cosmic rays [ http://www.srl.caltech.edu/personnel/dick/ cos_encyc.html ] strike the top of the Earth's atmosphere. Cosmic rays were discovered unexpectedly [ http://helios.gsfc.nasa.gov/ hist_1900.html ] in 1912. It is now known that most cosmic rays are atomic nuclei [ http://en.wikipedia.org/wiki/Atomic_nucleus ]. Most are hydrogen [ http://periodic.lanl.gov/elements/1.html ] nuclei, some are helium [ http://periodic.lanl.gov/elements/2.html ] nuclei, and the rest heavier elements. The relative abundance changes with cosmic ray energy -- the highest energy cosmic rays tend to be heavier nuclei. Although many of the low energy cosmic rays [ http://en.wikipedia.org/wiki/Cosmic_rays ] come from our Sun, the origins of the highest energy cosmic rays remains unknown and a topic of much research. This drawing [ http://universe.nasa.gov/be/library/ images-library4.html ] illustrates air showers [ http://www.mpi-hd.mpg.de/hfm/CosmicRay/Showers.html ] from very high energy cosmic rays [ http://helios.gsfc.nasa.gov/ ]. Cosmic rays [ http://www.auger.org/qa/qa.html ] may even be important [ http://www.fnal.gov/pub/inquiring/matter/whysupport/index.html ] to Earth's weather -- common lightning [ http://antwrp.gsfc.nasa.gov/apod/ap040818.html ] may be triggered by passing cosmic rays.
Explanation
false