(Science Alert) The Sun has been spitting out some pretty powerful eruptions in the last few weeks, but one that took place a few days ago is a real doozy.
On March 12, Sun-monitoring spacecraft recorded a huge amount of material blasting away from the far side of the Sun from a coronal mass ejection. Detected as an expanding cloud, or halo, of solar debris, it raced away from the Sun at exceptionally high speeds of 2,127 kilometers (1,321 miles) per second.
The Sun spitting out flares and coronal mass ejections is nothing new, but this one was something special.
Usually, eruptions on the far side don’t tend to hit Earth, since they’re facing the opposite direction; but this one was so intense that satellites orbiting our planet picked up the signal of particles from the eruption accelerated by the eruption’s shockwave right into our corner of space.
It might seem like the Sun has been getting up to some shenanigans recently, and, well, it has. It’s heading into the peak of its cycle – a roughly 11-year loop in which the Sun’s activity peaks and declines. We’re heading for solar maximum, likely in the next year or two, when the Sun is most active, crawling with sunspots and erupting with powerful flares.
These cycles are linked to the Sun’s magnetic field, which reverses polarity every 11 years, although why it does so is something scientists are still trying to figure out. This polar flip takes place at solar maximum; the magnetic field at the poles weakens to zero, then re-emerges with the opposite polarity. North becomes south, south becomes north.
During this time, sunspots appear in large numbers. These are temporary patches on the Sun with stronger magnetic fields, the lines of which often tangle, snap, and reconnect. When this occurs, a tremendous amount of energy is unleashed in the form of a solar flare. These can sometimes produce coronal mass ejections, in which tons of material and magnetic fields are ejected from the Sun out into space.