As the Sun Turns: Solar Minimums and Maximums

[Maria]

The NOAA x-ray flux shows a steady condition with no B or C-class flaring for the past six hours.
cf. http://www.swpc.noaa.gov/products/goes-x-ray-flux

Comments from Belgium at 1321 UT. cf. http://www.sidc.be/products/meu/

COMMENT: Solar activity was low, no C-class flares in past 24 h. There is
only one region visible on disk (Catania group 67, NOAA active region 2692)
with beta magnetic field configuration. C-class flaring is possible.

Proton flux levels are at background values and are expected to remain so.
No Earth-directed seems were observed.

Solar wind speed is at 380 km/s with interplanetary magnetic field
magnitude of 7 nT. A sector boundary crossing was seen around 22:00 UT on
22 December, with polarity changing from positive to negative. The arrival
of a high speed stream from a negative coronal hole is expected within 24
h. Geomagnetic conditions have been quiet, active periods and possibly
minor storms are possible under the influence of the high speed stream.

TODAY'S ESTIMATED ISN : 027, BASED ON 08 STATIONS.

[Maria]

From NOAA: Beta AR2682 has been rapidly growing and is now geo-centered.

Joint USAF/NOAA Solar Region Summary
SRS Number 358 Issued at 0030Z on 24 Dec 2017
Report compiled from data received at SWO on 23 Dec
I. Regions with Sunspots. Locations Valid at 23/2400Z
Nmbr Location Lo Area Z LL NN Mag Type
2692 N18E03 087 0090 Dao 10 12 Beta

From Belgium's EISN|SILSO plot: Beta AR2682 now registers an impressive 28 sunspot cores.
cf: http://www.sidc.be/silso/eisnplot

[Maria]

From NOAA: Beta AR2682 has been rapidly growing and is now geo-centered.

Joint USAF/NOAA Solar Region Summary
SRS Number 358 Issued at 0030Z on 24 Dec 2017
Report compiled from data received at SWO on 23 Dec
I. Regions with Sunspots. Locations Valid at 23/2400Z
Nmbr Location Lo Area Z LL NN Mag Type
2692 N18E03 087 0090 Dao 10 12 Beta

From Belgium's EISN|SILSO plot: Beta AR2682 now registers an impressive 28 sunspot cores.
cf: http://www.sidc.be/silso/eisnplot

Here is the NOAA report for Dec. 25, 2017

Joint USAF/NOAA Solar Region Summary
SRS Number 359 Issued at 0030Z on 25 Dec 2017
Report compiled from data received at SWO on 24 Dec
I. Regions with Sunspots. Locations Valid at 24/2400Z
Nmbr Location Lo Area Z LL NN Mag Type
2692 N18W09 087 0160 Eai 12 12 Beta

Solar winds caused radio interference today.

Below is the report from Belgium's Royal Observatory earlier today. The number of sunspots (26) is lower than yesterday.

COMMENT: Solar activity was very low with X-ray flux remaining below B
level, apart from a single B1 flare from the only region on disk (Catania
group 67, NOAA active region 2692).

There is a relatively small chance for C -flaring over the next days.
Around 18:00 UT a filament eruption was visible in the North Eastern
quadrant. Coronagraph images do not reveal any associated CME signatures.
No Earth directed CMEs were recorded in coronagraph images.
Proton flux levels are at background values and expected to remain so.

Solar wind showed the expected arrival of the high speed stream from the
equatorial negative polarity coronal hole.

Solar wind speed first increased to 400 km/s but then declined again in the
afternoon of December 23. Since midnight it is increasing again to close to
500 km/s currently. Total magnetic field in the compression region measured
mostly in the 9-12nT range with a peak of over 14.5nT around 7:20UT. The
magnetic field Bz component was variable with excursions down to -9nT.
Solar wind speed is expected to further increase and remain elevated over
the next few days under influence of the coronal hole high speed stream.
Geomagnetic conditions were quiet to unsettled (local K Dourbes 0-2 and
NOAA Kp 0-3). Geomagnetic conditions are expected to be unsettled to active
with minor geomagnetic storms possible under the influence of the high
speed stream.
TODAY'S ESTIMATED ISN : 026, BASED ON 07 STATIONS.

[Maria]

Active Region AR2692 is slowly decaying with a decrease in its sunspot number.
Indeed, NASA's current photo of the sun shows that this active region is now barely visible.
https://sdo.gsfc.nasa.gov/assets/img/la ... _HMIIF.jpg

Belgium's consortium of astronomers reports the following sunspot data
at http://www.sidc.be/silso/home :

22 December : 24
23 December : 27
24 December : 25
25 December : 23
26 December : 15

Again, this information above clearly shows that the number of sunspots in AR2692 is decreasing day by day.

[Maria]

AR2692 has now decayed to an Alpha.

Joint USAF/NOAA Solar Region Summary
SRS Number 362 Issued at 0030Z on 28 Dec 2017
Report compiled from data received at SWO on 27 Dec
I. Regions with Sunspots. Locations Valid at 27/2400Z
Nmbr Location Lo Area Z LL NN Mag Type
2692 N17W46 085 0010 Axx 01 01 Alpha

Here is the listing of recent estimated sunspot numbers for December 2017 from Belgium.
http://sidc.be/silso/eisnplot

23 December : 27
24 December : 25
25 December : 22
26 December : 16
27 December : 13

[Maria]

Yesterday, Dec. 28, 2017, we had a B-class solar flare (8.3).

Apparently, this originated from the farside of the sun according to Belgium's Royal Observatory.

INFO FROM SIDC - RWC BELGIUM 2017 Dec 29 12:30UTC

Solar activity was low, no C-class flares in past 24 h. There are no active
regions visible on the solar disk. A CME was observed in LASCO-C2 starting
at 23:12 UT on 28 December, directed towards the south east and associated
with a B8.3 flare (peak 22:29 UT), behind the east limb. This CME is
backsided and will not affect the Earth. No C-class flares expected
(although this region behind the limb may change the situation).

Thus, we could be viewing another sunspot soon as the sun turns, but for now, the sun remains spotless.

[Maria]

New Comment from Belgium's Royal Observatory
cf. http://www.sidc.be/products/meu/

Another spotless day.

COMMENT: The solar activity was quiet over the past 24 hours. The visible
solar disc is spotless and no C-class flare has been recorded. Quiet
flaring conditions are expected for the next 24-hour period.

No Earth directed Coronal Mass Ejection has been observed. The greater than
10 MeV solar protons flux remained at nominal levels over the past 24 hours
and is expected to remain so.

The solar wind measurements indicated the onset of a Corotating Interaction
Region announcing the soon arrival of the high speed solar wind stream
(HSS) associated with the Coronal Hole (which has crossed the central
meridian on Dec 28. The wind speed shows a gradual increase from the
nominal values (around 350 km/s) to the current values ranging from 450 to
470 km/s. The interplanetary magnetic field has shown a sudden increased on
Dec 31 around 18:00 UT due to the arrival of a Corotating Interaction
Region, magnetic field magnitude was fluctuating between 9 and 12 nT and
the Bz component between -11 and 10 nT. The enhanced solar wind conditions
are expected to persist until while under the influence of the HSS
associated with the coronal hole.

Disturbed geomagnetic conditions were observed due to the enhanced
conditions of the solar wind: NOAA reported a minor storm (Kp=4) at 3:00 UT
on Jan 01, while Dourbes stations observed unsettle conditions (with K=3 at
03:00 UT on Jan 01). As enhanced solar wind conditions are expected to
persist, further minor to moderate geomagnetic storms cannot be excluded,
especially if Bz component remains negative for long period of time.

Below is the revised (in green ink) plot from Belgium.
cf. http://www.sidc.be/silso/home
This time, they have revealed their changes for all to see.
Openness is good for the scientific community.
The green diagonal line shows the beginning of December through December 31,
and the small blue horizontal line shows the estimated average sunspot number (around 7).