A compilation of the most memorable space weather moments of 2022 can be found underneath. Using the versatile Space Weather JHelioviewer (SWHV) software, a ***MOVIE*** was created (available on YouTube) containing one or more clips of each event. Usually, images from SDO, STEREO, and SOHO have been used, occasionally supplemented with imagery from Solar Orbiter, ROB/USET and the GONG/H-alpha network.
As this chronological list concerns mostly punctual events on the Sun, it does not contain clips from other noteworthy events in 2022, such as e.g. the SpaceX satellite loss on 4 February, the passing away of Eugene Parker (15 March), the publication of Frédéric Clette's book "Le Soleil", space weather effects from a gamma-ray burst on 9 October, and disturbed GNSS applications from a minor geomagnetic storm on 7 November.
Happy viewing!
Event 1: 15-16 February - Violent eruption on the solar farside
Late on 15 February, a full halo coronal mass ejection (CME) was observed with a speed of 2200 km/s. It quickly became clear that this was a farside event, and that the CME was not directed to Earth. The Full Sun Imager (FSI) on board Solar Orbiter, which was trailing the Earth by 17 degrees, was able to track the ejected prominence material in EUV (extreme ultraviolet) passbands for up to more than 6 solar radii, the first observed in 30.4 nm emission at such a great height. The eruption must have been extremely violent because, despite the poor magnetic connection of the source location on the Sun with the Earth, GOES-16 still recorded a mild enhancement in the greater than 10 MeV proton flux.
Ref: STCE newsitem of 2 March, Press release, Mierla et al. (2022)
Event 2: 30 March-10 May - Six (6!) X-class flares in 6 weeks
The second quarter of 2022 saw a significant increase in complex sunspot groups and solar flaring activity. Six of the 7 X-class flares produced in this year happened within a period of only 6 weeks. NOAA 12994 (on 17 and 30 April) and NOAA 13006 (on 3 and 10 May) produced 2 X-class events each, NOAA 12975 produced an X1.3 flare on 30 March, and NOAA 12992 produced the strongest event of the year on 20 April (X2.2). The EUV and x-ray radiation disturbed the dayside ionosphere, leading to problems for HF communications (High Frequency) users such as mariners, radio meteor observers, and in aviation. Only the CME associated with the first X-class event was able to stir some geomagnetic unrest (minor storm on 2 April), the CMEs associated with the other 5 events didn't have an earth-directed component.
Ref: STCE newsitems for the X-class flares of 30 March, 17 April, 20 April, 30 April, 3 May, and 10 May
Event 3: 13 June - Long Duration M3 flare
Fairly unimpressive sunspot region NOAA 13032 produced an M3.4 flare on 13 June. It was a long duration event (LDE), lasting 2 hours and 14 minutes. An enhancement in the greater than 10 MeV proton flux was observed and lasted for several days, however the values remained well below the alert threshold of 10 pfu. In fact, 2022 would see only 5 proton events, all minor solar radiation storms ("S1" on the NOAA scale) with the strongest one reaching only 32 pfu on 2 April related to an M4 flare by NOAA 12975. The 13 June LDE was associated with a CME, but the bulk was directed behind the Earth. The CME had a weak earth-directed component, but the glancing blow produced only a small and brief disturbance in the solar wind parameters on 15 June, driving Kp to minor geomagnetic storm levels.
Ref: STCE newsitem of 20 June and 6 April
Event 4: 15 July - Filament eruption
Starting around noon on 15 July, a filament in the Sun's northern hemisphere just west of the central meridian erupted. This filament had developed a solar rotation ago and its length was comparable to the Earth-Moon distance, i.e. a length between 370.000 and 390.000 km. In H-alpha (red portion of the solar spectrum ; 656.28 nm), the eruption was observed with instruments from the GONG network as well as with the H-alpha telescope of the ROB/USET. These images show that the filament snapped near its middle, with portions flowing to the east and west along the neutral line, i.e. the "border" between opposite magnetic fields. Also, a small portion of the east end of the filament survived the initial eruption, preferring to erupt by itself just a few hours later, on 16 July around 03:00UTC. The associated CME had an earth-directed component, but caused only a minor geomagnetic storm (Kp=5) on 18 July. The Sun was peppered with filaments around 8 May and 12/13 July.
Ref: STCE newsitems of 28 June and 18 July
Event 5: 23 July - Farside filament eruption
A fast halo CME was observed by SOHO and STEREO-A coronagraphs late on 23 July. As the eruption occurred on the farside of the Sun, solar observers had obviously no idea what the source of the eruption was. That is... until observations made by the Solar Orbiter became available last week. As it turns out, on 23 July, the spacecraft was located almost diametrically opposed to STEREO-A, preceding the Earth by about 151 degrees. Its Full Sun Imager (FSI), one of SolO's 3 EUV telescopes, showed the source of the eruption to be a long and solid filament, which is a cloud of ionized gas suspended above the solar surface squeezed between regions of opposite magnetic polarity. Becoming unstable somewhere between 17 and 18UTC, the violent eruption ejected the filament that splitted in 2 during the process. From Solar Orbiter/FSI's point of view, the portions moved in resp. the southeast ("lower left") and northwest ("upper right") direction. In comparison, STEREO-A's coronagraph saw the two portions of the ejected filament (CME core) as if in a mirror, with the first portion moving to the southwest ("lower right") and the other portion to the northeast ("upper left").
Ref: STCE newsitem of 20 September
Event 6: 28-29 August - Impressive solar eruption at the southwest limb
NOAA 3088 started its development on 24 August in the southwest solar quadrant, reaching a maximum sunspot area around 3 times the total surface area of the Earth. The flare production by this region was quite high, with 13 M-class flares between 27-30 August, the last few when the sunspot group had already rounded the solar limb early on 29 August. One of its strongest flares was an M6.7 flare on 28 August (peak time at 16:19 UTC). An impressive sight in EUV images, the post-flare coronal loops reached a height around 180.000 km, which is about half the average Earth-Moon distance. The powerful CME associated with this eruption kicked aside a much slower moving CME associated with a C-class flare produced by the same region earlier that day.
Ref: STCE newsitem of 6 September and 13 September
Event 7: December 2022 - Monthly sunspot number exceeds 100!
After a fast increase during the first few months of 2022, sunspot activity had been hovering between 75 and 95 for nearly 6 months. Then, in December, the solar activity shifted into a higher gear. With 112.8, the monthly sunspot number exceeded 100 for the first time in SC25. On the average, about 7 sunspot groups were visible on the solar disk throughout most of the month, with even 10-11 groups on 14-15 December. Using eclipse glasses, NOAA 13153 was visible with the naked eye for a few days early in the month. The increased sunspot activty was accompanied by a strong increase in flaring activity. In particular active region NOAA 13165 was very active, producing no less than 23 M-class flares in just 3 days, thus becoming the most prolific M-class flare source of the year. The enhanced activity late in 2022 continued throughout the next months.
Ref: STCE newsitem of 2 January 2023
