Sun and its interactions with the Earth and the solar system

Understand the Sun and its interactions with the Earth and the solar system

At the center of our solar system is a magnetic variable star, our Sun, that drives the space environment of the planets, including the Earth, and sculpts the flows of in-terplanetary space itself. At the dawn of the space age, the earliest experiments discovered this link between the Sun and the Earth: Explorer 1 (1958—radiation belts), Mariner 2 (1962—solar wind) and Skylab (1973—coronal mass ejections and coronal holes as the source of solar wind). This led to the understanding that stars interact with the universe not just through gravity and photon radiation but also through electromagnetic fields and particles. 

Our planet is immersed in a seemingly invisible yet exotic and inherently hostile environment. Above the protective cocoon of Earth’s atmosphere is a plasma soup com-posed of electrified and magnetized matter entwined with penetrating radiation and energetic particles. Our Sun’s energy output, which varies on time scales from milliseconds to billions of years, forms an immense structure of complex magnetic fields. Inflated by the so-lar wind, this colossal bubble of magnetism, known as the heliosphere, stretches far beyond the orbit of Pluto. This extended atmosphere of the Sun drives some of the greatest changes in our local space environment—affecting our magnetosphere, ionosphere, atmosphere, and potentially our climate.

• Understand the Nature of Our Home in Space: Understand how human society, technological systems, and the habitability of planets are affected by solar variability interacting with planetary magnetic fields and atmospheres.

• Safeguard the Journey of Exploration: Maximize the safety and productivity of human and robotic explorers by developing the capability to predict the extreme and dynamic conditions in space.

Sun and its interactions with the Earth and the solar system

At the center of our solar system is a magnetic variable star, our Sun, that drives the space environment of the planets, including the Earth, and sculpts the flows of in-terplanetary space itself. At the dawn of the space age, the earliest experiments discovered this link between the Sun and the Earth: Explorer 1 (1958—radiation belts), Mariner 2 (1962—solar wind) and Skylab (1973—coronal mass ejections and coronal holes as the source of solar wind). This led to the understanding that stars interact with the universe not just through gravity and photon radiation but also through electromagnetic fields and particles. 

Our planet is immersed in a seemingly invisible yet exotic and inherently hostile environment. Above the protective cocoon of Earth’s atmosphere is a plasma soup com-posed of electrified and magnetized matter entwined with penetrating radiation and energetic particles. Our Sun’s energy output, which varies on time scales from milliseconds to billions of years, forms an immense structure of complex magnetic fields. Inflated by the so-lar wind, this colossal bubble of magnetism, known as the heliosphere, stretches far beyond the orbit of Pluto. This extended atmosphere of the Sun drives some of the greatest changes in our local space environment—affecting our magnetosphere, ionosphere, atmosphere, and potentially our climate.

• Understand the Nature of Our Home in Space: Understand how human society, technological systems, and the habitability of planets are affected by solar variability interacting with planetary magnetic fields and atmospheres.

• Safeguard the Journey of Exploration: Maximize the safety and productivity of human and robotic explorers by developing the capability to predict the extreme and dynamic conditions in space.