The sun blazes with fascinating phenomena, which is infinitely cooler when imaged in ultraviolet. Especially when the image in question is what appears to be a cosmic chasm of doom.
“The hole is easily recognizable as the dark expanse across the top of the Sun and extending down in each side,” NASA demystified this scary-looking darkness in a recent statement. “Coronal holes are magnetically open areas on the Sun that allow high-speed solar wind to gush out into space. They always appear darker in extreme ultraviolet.”
Coronal holes happen when the sun’s temperamental magnetic field has one of the many tantrums that also cause sunspots or explode into solar flares. This particular kind of outburst, in which the magnetic field temporarily backs off a thinner area of the upper atmosphere (corona), ripping a hole into the corona that suffers a gas and energy deficit from so many solar particles escaping into space. Everything becomes colder and darker (at least that part is like something out of a horror movie) until that part of the magnetic field decides to behave and crawls back to where it was supposed to be.
What happens on the sun doesn’t necessarily stay over 90 million miles from Earth. Supercharged solar winds can cause geomagnetic storms on our planet, and the larger the hole, the more potential impact on our magnetosphere. Geomagnetic storms and radiation storms and can warp the function of power grids and satellites and cause radio blackouts. They can also set off some amazing visual effects. If you were lucky enough to be in a place where you could Instagram the auroras that streaked across the night sky earlier this month, the free light show comes from those rogue solar winds interfering with our magnetosphere. So you were pretty much seeing the rainbow vomit of that coronal hole.
The sun will keep getting creepier as it approaches its solar minimum in 2019, with more coronal holes continuing to open up and send geomagnetic storms our way until the cycle restarts itself. The solar cycle really could mean imminent doom for for satellites in the wrong place at the wrong time, which is why NOAA believes it is so critical to use the cycle for determining how long they can hang out in low-Earth orbit. The higher the solar maximum, the less time a satellite has, and vice versa. Seems that orbiting spacecraft are safe as the solar minimum creeps up until you factor in the increase in Earthbound solar winds as more and more coronal holes rip open and release them.
Just forget about all the potentially catastrophic effects of this phenomenon for now and enjoy the unreal photo, which may end up as your next desktop wallpaper.