Big Questions for Heliophysics

Heliophysics is a new field of science — the determination of the mechanisms and processes of the solar system as driven by the Sun. NASA is working to study the big science questions to help us understand the complex behavior of the Sun to develop the capability to predict changes to Earth and its space environment. A collection of spacecraft, the Heliophysical System Observatory, patrols the expanse from the Sun to the frontiers of the solar system and beyond. This observatory reveals not a placid star and isolated planets, but an immense, dynamic, interconnected system of which our home planet is part and through which space explorers must journey.

What causes the sun to vary?

We live in the extended atmosphere of a magnetic variable star that drives our solar system and sustains life on Earth. Our Sun varies in every way we can observe it. The Sun gives off light in the infrared, visible, ultraviolet, and at x-ray energies, and it gives off magnetic field, bulk plasma (the solar wind) and energetic particles moving up to nearly the speed of light, and all of these emissions vary.

How do the Earth and Heliosphere respond?

Our planet is immersed in this seemingly invisible yet exotic and inherently dangerous environment. Above the protective cocoon of Earth’s lower atmosphere is a plasma soup composed of electrified and magnetized matter entwined with penetrating radiation and energetic particles.

What are the impacts on humanity?

Modern society depends heavily on a variety of technologies that are susceptible to the extremes of space weather — severe disturbances of the upper atmosphere and of the near-Earth space environment that are driven by the magnetic activity of the Sun. Strong electrical currents driven in the Earth’s surface during auroral events can disrupt and damage modern electric power grids and may contribute to the corrosion of oil and gas pipelines.