As the Sun Turns: Solar Minimums and Maximums

[Maria]

Oops! If there is one thing about our sun, it continually changes.

We just had a B1.9, and the B flaring activity is now sustained. This could lead to a C-class solar flare.

Visit GOES X-Ray flux at https://www.swpc.noaa.gov/products/goes-x-ray-flux

[Maria]

Although AR2733 perseveres with a show of force, it will soon disappear for a two week transit around the far side of the sun.

Today, January 29, 2019 at 05:07:00 UTC, there was a B2.4 solar class flare.

[Maria]

COMMENT: NOAA AR 2733 produced three C-class flares in the past 24 hours,
the strongest one was a C5.2 flare peaking at 06:11 UT. This AR is rotating
over the west limb and no other AR is visible, low solar activity is thus
expected, although isolated C-class flares remain possible.

No Earth directed Coronal Mass Ejections (CMEs) have been detected. Solar
protons have remained at background levels over the past 24 hours.

The solar wind speed is at 280 km/s with interplanetary magnetic fields of
2 nT. Geomagnetic conditions have been quiet. The fast solar wind
associated with a negative polarity equatorial coronal hole is expected to
arrive to the Earth within 24 hours, causing disturbed conditions (most
likely up to K = 5).

TODAY'S ESTIMATED ISN : 000, BASED ON 11 STATIONS.

[Maria]

Comment from Belgium Royal Observatory:

COMMENT: No C-class flares in the past 24 hours, NOAA AR 2733 rotated over
the west limb. There are no active regions visible. Eight B-class flares
were observed (still from NOAA AR 2733), the strongest one was a B9.7 flare
peaking at 17:05 UT on 30 January. Low solar activity is expected.

No Earth directed Coronal Mass Ejections (CMEs) have been detected. Solar
protons have remained at background levels over the past 24 hours.

The solar wind speed is at 350 km/s with interplanetary magnetic fields of
14 nT. Geomagnetic conditions have been quiet. Solar wind density, speed,
temperature and magnetic field have been increasing since last night,
together with a sector boundary crossing (from positive to negative
magnetic field polarity), marking the arrival of the fast solar wind
associated with a negative polarity equatorial coronal hole. Disturbed
geomagnetic conditions (most likely up to K=5) are expected for the next 48
hours.

TODAY'S ESTIMATED ISN : 000, BASED ON 16 STATIONS.

[Maria]

Comment from the Royal Observatory in Belgium
So far, the active region has not developed significantly but instead seems to be decaying.
Stay tuned.

COMMENT: There are no active regions on the visible solar disk, no C-class
flares in past 24 h (only minor B-class flaring). Solar activity has been
very low and is expected to remain so, although a region rotating into view
from the east limb may increase activity slightly in the coming hours.

No Earth directed Coronal Mass Ejections (CMEs) have been detected. Solar
protons have remained at background levels over the past 24 hours.

The solar wind speed is at 550 km/s with interplanetary magnetic fields of
10 nT. Geomagnetic conditions reached active values locally (k=4 at
Dourbes) and minor storm levels planetary (Kp=5), from 21:00 UT until
midnight, as a consequence of the arrival of the high speed stream from a
negative polarity coronal hole (with speeds reaching 550 km/s and magnetic
fields up to 20 nT). Disturbed geomagnetic conditions are expected for the
next 48 hours (up to minor storm levels).

TODAY'S ESTIMATED ISN : 000, BASED ON 10 STATIONS.

[Maria]

Deep solar doldrums can be seen as the solar activity drops into the A0 levels. Look at the red line.

Please visit: https://www.swpc.noaa.gov/products/goes-x-ray-flux

The data from Belgium has just been posted for the month of January 2019.

The average mean for the International Sunspot Numbers for January 2019 was 7.8.
The approximate mean for all the months of 2018 was 7.1.
So far, the month of February has shown a deep solar minimum with zero sunspots spotted.
This has been a five day straight run of spotlessness, and the comment from Belgium's Royal Observatory notices this quiet.

COMMENT: The solar activity has been quiet over the past 24 hours. The
visible solar disc was spotless, and the X-ray flux remained below B-level.
Flaring conditions is expected to remain at low levels.

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 Earth is still inside the influence of the speed stream associated with
negative polarity coronal hole that had reached the central meridian last
week. The solar wind speed decreased from about 568 km/s to 410 km/s over
the past 24 hours, and the interplanetary magnetic fields remained below 5
nT. The solar wind parameters are expected to globally return towards an
ambient background and slow solar wind speed regime.

The geomagnetic conditions were mostly quiet and ranged between Kp index
0-3 (NOAA) and local K index 0-2 (Dourbes) over the past 24 hours. They are
expected to remain mostly quiet, unsettled conditions periods remain likely
to happen as the solar wind speed is still elevated (due to the extended
and patchy shape of the coronal hole).
TODAY'S ESTIMATED ISN : 000, BASED ON 13 STATIONS.

[Maria]

I am back on line! Welcome everyone.

February at 0.8 has had the lowest International Sunspot Number (ISN) since the start of Sun Cycle 24. There were only two days of sunspots:
February 13 at 12
February 21 at 11

12 + 11 = 23
23 sunspots/28 days in February = a mean of 0.8 for the month of February 2019

March started out with no sunspots, but on March 5, later in the day, two active regions began to appear.

Here is the daily comment from Belgium's Royal Observatory for March 5 around 12:30 UT.

COMMENT: The solar activity has been quiet over the past 24 hours. The
X-ray flux remains below B-level. Two regions show some mild activity, but
no sunspots are clearly visible on the disc. Solar activity is expected to
remain at low levels.

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.

Solar wind speed fluctuated around 350 km/h and 450 km/h, the total
interplanetary magnetic field strength was steady and remained below 6.5
nT. The Bz component fluctuated between -5 nT and 5 nT. The solar wind
parameters are expected to remain slightly enhanced due to several small
patchy equatorial coronal holes (negative polarity) that dominate the
current space weather conditions for the following days with a wind speed
ranging from nominal values (around 350 km) to 400-450 km/s.

The geomagnetic conditions were quiet over the past 24 hours. The
geomagnetic conditions are expected to remain mostly quiet. In response to
the slightly enhanced interplanetary magnetic field due to small patchy
equatorial coronal holes and possible prolonged period of southward
directed Bz component, short periods of unsettle are possible.

TODAY'S ESTIMATED ISN : 000, BASED ON 15 STATIONS.

The text message from international astronomers at Belgium is printed below.
The comments in italics are mine. The range of reports for March 5 is
between 0 to 15. Apparently, the first 15 station reports have reported no sunspots.
Today's (March 6) report shows a reading of 16 sunspots with only a 2.0 standard deviation (std).

March 2019

2019 03 01 2019.163 0 0.0 17 18
2019 03 02 2019.166 0 0.0 19 20
2019 03 03 2019.168 0 0.0 16 17
2019 03 04 2019.171 0 0.0 26 30
2019 03 05 2019.174 8 7.3 32 34 – very high std of 7.3 with 2 outliers
2019 03 06 2019.177 16 2.0 11 12

Looking at http://www.thesuntoday.org/the-sun-now/, and observing the HMI magnetogram colored photo, I noticed an unusual sunspot in the northern hemisphere, which looked like it was already sporting a green hat for St. Patrick's day.

This in from http://www.spaceweather.com:

WHAT KIND OF SUNSPOT IS THAT? Today, a tiny sunspot is struggling to form in the sun's northern hemisphere. It is so small, it has not yet been numbered, and it may fade away before the day is done, leaving the sunspot number technically zero. Even if it vanishes, though, this funny little sunspot is worth mentioning because of its tilted magnetic field:

This is a magnetogram (magnetic map) of the sun obtained on March 5th by NASA's Solar Dynamics Observatory. The sunspot is inset. Note how its magnetic field is almost orthogonal to other patches of magnetism elsewhere on the solar disk.

Sunspots are islands of magnetism floating on the surface of the sun. Like all magnets, they have two poles, plus (+) and minus (-). Usually these poles are aligned almost parallel to the sun's equator. Today's sunspot is almost perpendicular.

Could this be a sunspot from the next solar cycle? Right now, Solar Cycle 24 is decaying into a deep Solar Minimum. Solar Cycle 25 is still in the offing. According to Hale's Law, sunspot magnetic fields reverse polarity between solar cycles. If this sunspot continues to grow--and if its magnetic axis tilts a bit to the right--Hale's Law would tag it as a member of Solar Cycle 25.

Solar cycles always mix together at their boundaries. Indeed, ephemeral sunspots possibly belonging to Solar Cycle 25 have already been reported on Dec. 20, 2016; April 8, 2018; and Nov. 17, 2018. Perhaps, when the day is done, we might add March 5, 2019, to the list. Stay tuned.