National Aeronautics and Space Administration

What are the hazards and resources in the Solar System environment that will affect the extension of human presence in space?

Harsh conditions in the space environment pose significant risks for the journey of exploration.  Although space is a near-vacuum, the very-thinly-spread particles and fields are like an ocean that can affect the spacecraft and astronauts that travel through it.  Like seafaring voyagers, space explorers must be constantly aware of the current space weather and be prepared to handle the most extreme conditions that might be encountered.

Although much of the dramatic variability in the space environment is driven by solar activity, such as flares and coronal mass ejections, understanding the more routine variations driven by rotation or slowly evolving structures is also important.