The Sun does far more than provide Earth with light and heat. Two recent NASA-funded studies suggest that events from the Sun's distant past may have influenced Earth's climate in unexpected ways, from helping drive ancient temperature shifts to keeping the young planet warm enough for liquid water and possibly life.
One study from NASA's SHIELD (Solar Wind with Hydrogen Ion charge Exchange and Large-Scale Dynamics) center, one of NASA's DRIVE (Diversify, Realize, Integrate, Venture, Educate) Science Centers, examines how the heliosphere moved through the Milky Way over time. The heliosphere is the vast protective bubble produced by the Sun that surrounds the solar system. Researchers found that changes in the galactic environment around this bubble may have affected conditions on Earth.
A separate study led by a NASA scientist explores another ancient puzzle: how a much dimmer young Sun could have kept Earth warm. The findings suggest that powerful solar eruptions may have helped generate strong greenhouse gases in Earth's early atmosphere.
The Sun's Journey Through the Milky Way
Earth's climate has changed dramatically over tens of millions of years. At various points, major ice ages temporarily lowered global average temperatures by several degrees, while other periods brought repeated swings between warmer and colder conditions.
