The sun is far from quiet.
Yesterday, Dec. 17, the sun fired out an ‘extremely rare’ farside coronal mass ejection (CME) — a vast plume of plasma and magnetic field.
According to NASA’s Space Weather Database of Notifications, Knowledge, Information (DONKI), the ER (‘extremely rare’) CME clocked in with an estimated speed of around 1,964 miles per second (3,161 km/s!). The eruption occurred from the sun’s farside and has no Earth-directed components. Slower CMEs often take two to three days to arrive whereas if this CME had been Earth-directed it would have arrived in approximately less than 18 hours.
“BOOM! Big and very fast full-halo CME in LASCO imagery this afternoon,” aurora and storm chaser Jure Atanackov wrote in a post on X.
BOOM! Big and very fast full-halo CME in LASCO imagery this afternoon. Fast, most of it cleared the C2 field of view in under 1 hour. The culprit is again an active region on the far side, likely in the southern hemisphere, near the central meridian. Wow! pic.twitter.com/HaEFcioOQyDecember 17, 2024
This is the fourth farside CME in 10 days, hinting at a very active hidden sunspot, yet to rotate into view, according to Spaceweather.com. We should expect the explosive culprit to rotate toward Earth next week.
But the super speedy CME wasn’t the only impressive eruption from our star yesterday. Two prior CMEs erupted during fiery solar filament eruptions on the southeastern limb.
Solar filaments are vast clouds of ionized gas above the solar surface. When they become unstable they either fall back onto the sun or erupt into space, hurling a CME out into space. When Earth is in the firing line of such eruptions, it can trigger geomagnetic storms — disturbances in Earth’s magnetosphere. Although all three eruptions released CMEs, none are predicted to be Earth-directed.
“Two very photogenic eruptions of plasma from the eastern edge of the Sun this morning! Neither are Earth-directed,” solar astrophysicist Ryan French wrote in a post on X.
Two very photogenic eruptions of plasma from the eastern edge of the Sun this morning! Neither are Earth-directed.(Observations from the GOES/SUVI instrument). #spaceweather pic.twitter.com/OYqX2frI6rDecember 17, 2024
A wider field of view with Lasco coronograph imagery of the sun’s corona shows the intricate structure of the two CMEs released from the filament eruptions.
“The second coronal mass ejection in particular shows beautiful structure as it erupts!” French continued.
Here’s another clip with an extended time period and wider field-of-view coronagraph imagery. The second coronal mass ejection in particular shows beautiful structure as it erupts! pic.twitter.com/W6YwbK7YkYDecember 17, 2024