Why Investigate Sun-Earth Connections?

We live in the extended atmosphere of an active star, the sun. While sunlight enables and sustains life, the sun's variability produces streams of low and high-energy particles and radiation that can affect life.

Under the protective shield of its magnetic field and atmosphere, the Earth is an island in the solar system where life has developed and flourished. The origins and fate of life on Earth are intimately connected to the way the Earth responds to the sun's variations. Understanding the changing sun and its effects on the solar system, life and society is the goal of NASA's Heliophysics Theme.

Some Sun-Earth Connection missions fall under the larger NASA Living With a Star program that addresses the effects of the Sun's highly variable radiation and particle emission upon the Earth and its effect on life and society. Presently, there are two elements in the LWS campaign:

(a) Solar dynamics elements (Solar Dynamics Observatory/Sentinels spacecraft) that observe the Sun, track the disturbances originating there through the heliosphere, and

(b) Geospace dynamics elements (Geospace Missions Network) consisting of spacecraft located in the magnetosphere and ionosphere to define the geospace response to varying solar and solar wind input.