National Solar Observatory | 2017 Jul 28
August 21st will bring a history-making opportunity for the entire United States. On that day, every person in the country, including Hawaii and Alaska, will have an opportunity to witness at least a partial solar eclipse as the moon moves in front of the Sun. If you have the good fortune to be along the path of totality, stretching from Oregon to South Carolina, you will get to witness one of the most awe-inspiring views in nature – the wispy wonders of the solar corona.
The adjacent image shows field lines of a solar coronal magnetic model based on measurements from the National Solar Observatory Integrated Synoptic Program (NSO/NISP) one solar rotation, or 27.2753 Earth days, before the August 21, 2017 total solar eclipse. The view offers and example of what observers of the total solar eclipse will see on August 21st. The solar disk has been occulted leaving only the off-limb magnetic structure visible. The visible field lines indicate how the corona during a total solar eclipse would appear according to the model. The solar wind flows outward from the Sun along open field lines. Closed field lines, where the lines loop back onto the Sun, trap coronal plasma. As a result, the corona in closed structures appear brighter than the open corona in eclipse images. Closed and open lines are shown white and dark grey in the plot. The largest closed structures represent the helmet streamers that we see during the total solar eclipse. ...
