A long coronal hole can be seen right down the middle of the sun in this video captured by NASA's Solar Dynamics Observatory on March 23-25, 2016. Coronal holes are areas on the sun where the solar magnetic field extends up and out into interplanetary space, sending solar material speeding out in a high-speed stream of solar wind.
Scientists study these fast solar wind streams because they sometimes interact with Earth's magnetic field, creating what's called a geomagnetic storm, which can expose satellites to radiation and interfere with communications signals. This video was captured in extreme ultraviolet wavelengths of 193 angstroms – a type of light that is typically invisible to our eyes, but is colorized here in bronze.
Provided by NASA