As the Sun Turns: Solar Minimums and Maximums

[Maria]

Today, July 16, 2018 (Monday), NOAA has reported that the sun is spotless:

Issued: 2018 Jul 16 0030 UTC

Prepared jointly by the U.S. Dept. of Commerce, NOAA,

Space Weather Prediction Center and the U.S. Air Force.

#
Joint USAF/NOAA Solar Region Summary
SRS Number 197 Issued at 0030Z on 16 Jul 2018
Report compiled from data received at SWO on 15 Jul
I. Regions with Sunspots. Locations Valid at 15/2400Z
Nmbr Location Lo Area Z LL NN Mag Type
None
IA. H-alpha Plages without Spots. Locations Valid at 15/2400Z Jul
Nmbr Location Lo
None
II. Regions Due to Return 16 Jul to 18 Jul
Nmbr Lat Lo
None

[Maria]

Belgium has now admitted that the sun is spotless. Furthermore, they expect solar wind increase by July 19 (Thursday). This will interfere with earthly communications.

While Belgium says that the recurrent active region (former AR2713) has broken the period of spotlessness after 15 days, NOAA and spaceweather.com are saying that today there have been 19 continuous days of spotlessness, which is a record breaker indicating that we are now in a deep solar minimum. However, Belgium is presenting an argument for a shorter minimum.

COMMENT: During last 24 hours solar activity was very low with only two
B-class flares reported. As the visible side of the solar disc is presently
spotless we do not expect flaring activity in the coming hours. Presently
available coronagraph images do not show signatures of the Earth directed
CMEs, and the solar protons are at the background level.

The in situ observations indicate arrival of the structure in the slow
solar wind, of presently unclear solar origin. Early this morning
interplanetary magnetic field started to increased (it reached the value of
about 10 nT) following, with of about 10 hours of the delay, the increase
of the density and drop of the temperature. The solar wind speed reached
its maximum value (during last 24 hours) of about 340 km/s early this
morning. The present value of the solar wind speed is 320 km/s and the
interplanetary magnetic field magnitude is about 8 nT.

Very patchy equatorial coronal hole, which seem to be connected to the low
latitude extension of the northern polar coronal hole, has reached central
meridian this morning. The increase of the solar wind speed, associated
with this coronal hole is expected late on July 19. Due to longer interval
of the negative value of the Bz component of the interplanetary magnetic
field (down to -8 nT) local station at Dourbes reported disturbed
geomagnetic conditions at about 09 UT today (K=4), and NOAA reported value
of the Kp=3.

The geomagnetic conditions are presently quiet to unsettled, and we expect
quiet geomagnetic conditions to persist in the coming hours.

TODAY'S ESTIMATED ISN : 000, BASED ON 27 STATIONS.

[Maria]

From Belgium's Royal Observatory.

The sun is now spotless. We possibly had a hyder flare event on July 13.

COMMENT: Solar activity is low and there were no even B-class flares
reported during last 24 hours. We expect such a low flaring activity to
persist in the coming hours.

Coronagraph images do not show signatures of the Earth directed CMEs, and
the solar protons are at the background level.

The in situ observations indicate arrival of the possible ICME. The
increase of the interplanetary magnetic field magnitude (up to 15 nT),
observed at about 20 UT on July 16, was followed by rotation of the
magnetic field phi angle, increase of the solar wind speed and temperature,
and decrease of the density. Solar counterpart of this structure is
presently unclear, and one of the possibility is the large prominence
eruption from the south-west quadrant of the Sun, observed on July 13 at
about 22 UT.

The solar wind speed is presently about 420 km/s and the interplanetary
magnetic field magnitude is about 6 nT.

The increase of the solar wind speed, associated with patchy equatorial
coronal hole which reached central meridian on July 16, is expected at the
Earth late on July 19.

Due to longer interval of the negative value of the Bz component of the
interplanetary magnetic field (down to -5nT) local station at Dourbes
reported slightly disturbed geomagnetic conditions o (K=4) at about 21 UT
on July 16, and NOAA reported value of the Kp=3.

The geomagnetic conditions are presently quiet, and we expect quiet
geomagnetic conditions to persist in the coming hours.
TODAY'S ESTIMATED ISN : 000, BASED ON 23 STATIONS.

[Maria]

NOAA's report continues to emphasize the silence spotlessness and dimming of the sun.
This is a deep solar minimum.

Issued: 2018 Jul 18 0030 UTC

Prepared jointly by the U.S. Dept. of Commerce, NOAA,

Space Weather Prediction Center and the U.S. Air Force.

#
Joint USAF/NOAA Solar Region Summary
SRS Number 199 Issued at 0030Z on 18 Jul 2018
Report compiled from data received at SWO on 17 Jul
I. Regions with Sunspots. Locations Valid at 17/2400Z
Nmbr Location Lo Area Z LL NN Mag Type
None
IA. H-alpha Plages without Spots. Locations Valid at 17/2400Z Jul
Nmbr Location Lo
None
II. Regions Due to Return 18 Jul to 20 Jul
Nmbr Lat Lo
None

In addition, here is an interesting alert, which was sent to my email account by http://www.spaceweather.com. I subscribe to Spaceweather.com alerts.

THREE WEEKS WITHOUT SUNSPOTS: The sun has been blank for 21 straight days--a remarkable 3 weeks without sunspots. This is an almost decade-class event. The last time the sun lost its spots for 21 consecutive days was in the year 2009 coming on the heels of an historic solar minimum. With the current stretch of blank suns, solar minimum conditions have definitely returned.

ref: http://www.spaceweather.com/archive.php ... &year=2018

[Maria]

Belgium's Royal Observatory now admits that there are no active regions on the sun: the sun is spotless.

COMMENT: Solar activity remains to be at very low level, and there were no
flares reported during last 24 hours. As there are no active regions
present at the visible side of the Sun, we expect such a low flaring
activity to persist in the coming hours.
No Earth directed CMEs were observed during last 24 hours, and the solar
protons remained at the background level.

The increase of the solar wind speed, associated with patchy equatorial
coronal hole that reached central meridian on July 16, is expected at the
Earth late on July 19. The unsettled to possibly, but not very probably,
active conditions are expected in the morning of July 20, due to the
expected arrival of the fast solar wind.
The geomagnetic conditions are presently quiet, and we expect them to stay
so in the coming hours.

TODAY'S ESTIMATED ISN : 000, BASED ON 22 STATIONS.

[Maria]

There is now a tiny sunspot area approaching the center of the sun.

It is near the equatorial coronal hole.

Will this last? Or will it fade away? Stay tuned.

[Maria]

NOAA mentions nothing about this sudden sunspot area, but this evening, one astronomer associated with Belgium's Royal Observatory also spotted it and gave it an estimated sunspot number of 11. http://www.sidc.be/silso/eisnplot

Issued: 2018 Jul 21 0030 UTC

Prepared jointly by the U.S. Dept. of Commerce, NOAA,

Space Weather Prediction Center and the U.S. Air Force.

#
Joint USAF/NOAA Solar Region Summary
SRS Number 202 Issued at 0030Z on 21 Jul 2018
Report compiled from data received at SWO on 20 Jul
I. Regions with Sunspots. Locations Valid at 20/2400Z
Nmbr Location Lo Area Z LL NN Mag Type
None
IA. H-alpha Plages without Spots. Locations Valid at 20/2400Z Jul
Nmbr Location Lo
None
II. Regions Due to Return 21 Jul to 23 Jul
Nmbr Lat Lo
None

]2018 07 01 2018.497 0 0.0 41 43
2018 07 02 2018.500 0 0.0 45 47
2018 07 03 2018.503 0 0.0 43 46
2018 07 04 2018.505 0 0.0 40 42
2018 07 05 2018.508 0 0.0 37 38
2018 07 06 2018.511 0 0.0 43 45
2018 07 07 2018.514 0 0.0 42 43
2018 07 08 2018.516 0 0.0 39 40
2018 07 09 2018.519 0 0.0 41 43
2018 07 10 2018.522 0 0.0 31 33
2018 07 11 2018.525 0 0.0 37 40
2018 07 12 2018.527 0 0.0 35 43
2018 07 13 2018.530 0 4.0 30 43
2018 07 14 2018.533 0 0.0 24 36
2018 07 15 2018.536 0 0.0 22 35
2018 07 16 2018.538 0 0.0 33 37
2018 07 17 2018.541 0 0.0 31 34
2018 07 18 2018.544 0 0.0 28 30
2018 07 19 2018.547 0 0.0 32 33
2018 07 20 2018.549 0 0.0 29 31
2018 07 21 2018.552 11 0.0 01 01

UPDATE: 12:16 AM Saturday, July 21: three astronomers associated with Belgium's Royal Observatory have now weighed in:
Two of the three astronomers do not see spots as the active region seems to have faded away, so currently the EISN is zero.

2018 07 21 2018.552 0 0.0 2 3