|The Sun's Face Has Many Features
1. Many times larger than magnetic loops, prominences majestically
rise far above the Sun's surface.
2. Bright explosions on the Sun --solar flares-- spew high-energy
electromagnetic waves (such as X-rays) into space.
3. Dark coronal holes are portals through which the fastest solar wind
escapes the Sun.
4. Small, dark regions on the Sun's surface, called sunspots,
contain strong magnetic fields.
|Our Dynamic Sun
Though the Sun is a constant in our lives, it is not tranquil. From deep within
our star, titanic energies rise to cause the surface to violently erupt. Hot tubes of plasma (called
magnetic loops) arc thousands of miles above the Sun, following invisible lines of magnetic force.
|Solar Explosions Blast Into Space
The Sun's corona can rip open and spew as much as 20 billion tons
of material into space -- equivalent to the mass of 200,000 cruise ships. These explosions are
known as coronal mass ejections (CMEs), the hurricanes of space weather.
When a CME ploughs into the solar wind, it can create a shock wave that accelerates particles
to dangerously high energies. Behind that shock wave, the CME expands into a huge cloud that
engulfs planets in its path with plasma.
Luckily for us, few CMEs are aimed at the Earth. If a CME erupts on the side of the Sun facing
us, the results around Earth can be spectacular and sometimes hazardous.