The Sun's New Year's Letter
posted: January 9, 2014

This promising letter arrived at the STCE’s Public Outreach Office on 1 January. It reads:

The Sun apparently wants to keep its New Year's resolutions. Indeed, on the very first day of the year it produced a great prominence eruption, a very strong solar flare, and one of the largest sunspot groups so far this solar cycle. This can be seen in this movie.

A solid and large prominence near the south east solar limb erupted around noon on 1 January. The accompanying bulb-like coronal mass ejection (CME) was not directed to Earth. The typical structure of a CME could easily be seen: a bright leading edge, a dark cavity, and the bright core filament. The CME moved at a rather slow speed of about 300 km/s.

At 18:52UT, magnetically complex sunspot group NOAA 1936 produced a strong M9.9 flare. It highlighted the increase in flaring activity which was already ongoing for several days (including an M3 flare on 29 December and an M6 flare on 31 December). The accompanying CME was not particularly significant and was mostly directed away from Earth.

In the course of the day, one of the largest sunspot groups so far this solar cycle rounded the south eastern solar limb. NOAA 1944 had about 9 times the surface area of the Earth. It has produced already various medium flares, the strongest of which was an M4-flare on 4 January. If the sunspots that currently compose the few magnetic deltas get larger, then more and stronger flares can be expected. No surprise this group continues to attract all the attention!

Credits - Data and imagery for the movie clips were taken from the SDO/AIA and SOHO/LASCO.