Coronal Holes

Context

• Scientists from the University of Graz (Austria), have developed a new neural network that can reliably detect coronal holes from space-based observations.

About

• Coronal holes are areas in the Sun's atmosphere that appear dark in X-ray and ultraviolet images of the Sun.
• The plasma (electrified gas) in these regions of the Sun's corona (it's upper atmosphere) is cooler and denser than in other parts of the corona.
• They appear dark because plasma particles can escape along the magnetic field from the solar surface into interplanetary space, leaving a ‘hole’ in the corona.
• The escaping particles form high-speed solar wind streams that can eventually hit Earth, causing geomagnetic storms.
• The appearance and location of these holes on the Sun varies in dependence of the solar activity, giving us also important information on the long-term evolution of the Sun.

https://scitechdaily.com/holes-in-the-solar-atmosphere-artificial-intelligence-spots-coronal-holes-to-automate-space-weather-predictions/