Context
Recently, NASA Solar Dynamics Observatory captured dark patches on the sun’s surface resembling eyes and a smile.
- NASA explained that the patches are called coronal holes.
About Coronal Hole
- Coronal hole can be understood as a patch of the Sun’s atmosphere with much lower density than elsewhere.
- In ultraviolet views of the Sun, coronal holes appear as dark splotches.
- These are regions where the Sun’s magnetic field lines are connected directly to interplanetary space, allowing solar material to escape out in a high-speed stream of solar wind, leaving a dark “hole” near the surface of the Sun.
- Coronal holes appear throughout the solar cycle, but can last for much longer periods of time during solar minimums, when the Sun is less active.
Importance
- These ‘coronal holes’ are important to understanding the space environment around the earth through which our technology and astronauts travel.
