2015 Volume 70 Issue 5 Pages 340-346
Paleoclimate studies have revealed that variations of Earth's climate may be under the control of solar activity, heliospheric environment, and the surrounding condition of our galaxy. One possibility is that galactic cosmic rays are playing important role in climate change by promoting chemical reactions in the atmosphere to produce cloud condensation nuclei and change the albedo of the Earth. We suggest that habitability of extra-solar planets may be also influenced by surrounding space environment and the condition of stellarsphere.