Wednesday, April 13, 2022





Watch 'Dead' Sunspot Explode, Launch Solar Material Towards Earth

Ed Browne - Yesterday
Newsweek

© NASA/Solar Dynamics Observatory/AIA, EVE, HMI science teams

A cloud of solar debris was hurled towards Earth on Monday, and a NASA spacecraft caught the moment on camera.

The video shows how a dark, s-shaped line appears on the sun's surface for a brief moment. It then explodes, throwing what appears to be a cloud of material towards the camera.

The s-shaped structure was described by SpaceWeather.com as the corpse of a "dead" sunspot called AR2987. Sunspots are dark areas in the sun's atmosphere that are associated with intense magnetic fields. They are dark because the magnetic fields surrounding them deflect heat away, leaving them cool at the center.

Sometimes these intense magnetic fields suddenly change their alignment, releasing huge amounts of energy and solar material from the region of the sunspot. These eruptions, like solar flares and coronal mass ejections (CMEs), are the sources of significant space weather events like geomagnetic storms on Earth.



The 's' or sigmoid shape of the sunspot seen in the NASA video is a phenomenon that has been seen before, occurring shortly before eruptions. According to a report from NASA researcher Alphonse Sterling in 2000, these sigmoid shapes are present in more than half of all CMEs. Sterling noted they could play an important role in space weather forecasting.

On Monday, the National Oceanic and Atmospheric Administration's Space Weather Prediction Center released a G2-class moderate-strength geomagnetic storm watch which noted that a cloud of material ejected from the sun's Region 2987—the solar eruption outlined above—will likely hit Earth on April 14.

G2-class storms are common and do not usually cause any issues. They may be associated with possible changes to the amount of drag experienced by satellites in Earth orbit, some radio fading at higher latitudes and the appearance of the Northern Lights in U.S. states like New York and Idaho. The highest class of geomagnetic storms, G5, are much more extreme and can cause entire power grid systems to go offline.

On Sunday a G3-class geomagnetic storm occurred, leading to shimmering auroras that were spotted by a passenger on a plane traveling over Alaska.

We can expect solar activity to increase in the coming years as the 11-year solar cycle is yet to reach its peak, which is measured by the number of observed sunspots. This number rises and falls over time.

The current solar cycle is predicted to reach its peak some time between 2025 and 2026, after which solar activity will begin to decrease until the solar minimum is reached by around 2035.



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