NASA Spots Square-Shaped 'Hole' in the Sun
A NASA spacecraft recently spotted a square-shaped "hole" formed by solar wind on the surface of the Sun.
Seen in the star's outer atmosphere, the dark square is a coronal hole that marks where solar winds are rapidly flowing from the Sun, Space.com reported.
NASA's Solar Dynamics Observatory (SDO) captured the unusual dark shape in a video taken last week.
"Inside the coronal hole you can see bright loops where the hot plasma outlines little pieces of the solar magnetic field sticking above the surface," SDO officials wrote in the video description. "Because it is positioned so far south on the Sun, there is less chance that the solar wind stream will impact us here on Earth."
The coronal hole appears dark because there is less material emitting light in the ultraviolet range of the spectrum used to make the video, according to a NASA video description.
These phenomena can appear on the Sun in all shapes and sizes, interrupting the star's brightness caused by hot plasma reined in by the Sun's magnetic field.
According to iO9, the coronal hole is a gap in the star's magnetic field where solar wind streams out, potentially affecting magnetic fields on the next planet. If a hole is facing us on Earth, the wind buffets our magnetic field, producing aurora.
But this particularly unusual hole is located far enough south on the Sun that it likely won't impact the Earth.
The SDO can view different layers of the Sun via different wavelengths of light. Typically, coronal holes are most visible in ultraviolet light and x-rays.
NASA's sun-watching SDO is also just one of several spacecraft keeping a close watch on the weather on Earth's parent star. In 2013, the sun experienced its peak activity of its 11-year solar weather cycle, according to Space.com.