On December 17, the Sun exhibited remarkable activity, launching an ‘extremely rare’ coronal mass ejection (CME) from its far side at an extraordinary speed.
According to NASA’s Space Weather Database of Notifications, Knowledge, Information (DONKI), the recent CME from the Sun’s farside traveled at a velocity of approximately 1,964 miles per second (3,161 km/s). This CME, notable for its speed and magnitude, originated from a region not directly facing Earth. Typically, CMEs take about two to three days to reach Earth when they are Earth-directed. However, if this particular CME had been headed our way, it would have arrived in under 18 hours.
Aurora and storm chaser Jure Atanackov shared on X, formerly known as Twitter, “BOOM! Big and very fast full-halo CME in LASCO imagery this afternoon.” This description refers to the full-halo effect captured in the LASCO imagery, indicating the expansive nature of the eruption. Atanackov identified the active region on the far side as the source, possibly in the Sun’s southern hemisphere near the central meridian.
The CME is the fourth farside incident in ten days, suggesting the presence of a very active hidden sunspot, which is anticipated to rotate into Earth’s view the following week. Meanwhile, additional solar activity was reported, with two earlier CMEs erupting due to fiery solar filament activities in the Sun’s southeastern region.
Solar filaments are dense clouds of ionized gas that hover above the Sun’s surface. Their instability can lead to either falling back onto the Sun or bursting into space, resulting in a CME. Such eruptions, when directed towards Earth, have the potential to cause geomagnetic storms, impacting Earth’s magnetosphere. Despite the three CMEs observed, none are expected to be Earth-directed.
Solar astrophysicist Ryan French commented on X about two visually striking plasma eruptions from the eastern edge of the Sun, emphasizing that neither eruption was Earth-directed. He noted, “The second coronal mass ejection in particular shows beautiful structure as it erupts!” French’s observations were supported by imagery from the GOES/SUVI instrument and a wider field of view from the Lasco coronagraph, showcasing the intricate structures of the CMEs.
This active solar period underscores the complexity and dynamic nature of solar phenomena. Ongoing observations by space weather agencies monitor these solar events to better understand their implications for Earth and space technology.
As solar activity continues to peak, it is crucial for scientists to track and analyze these eruptions to prepare for potential impacts on technological systems. While recent CMEs pose no direct threat to Earth, they highlight the Sun’s dynamic behavior and the importance of continued vigilance.
