As the Sun Turns: Solar Minimums and Maximums

[Maria]

Hey, Luke
Here is another fantastic shot of the sun as posted on http://www.spaceweather.com

BIG, CRACKLING SUNSPOT: Big sunspot AR2738 is crackling with minor B-class solar flares. Minor? On the sun, it's all relative. A typical B-class solar flare releases as much energy as 100 million WWII atomic bombs. Yesterday, Martin Wise of Trenton, Florida, caught the sunspot in mid-flare:

Only on the sun, which is itself a 1027 ton self-contained nuclear explosion, would such a blast be considered puny.

"Watching sunspot AR2738 and its B-class flares was like watching creation," says Wise, who also made an animation of the blast. "I used a Daystar Quark solar filter to safely take these pictures through my 8-inch Celestron telescope."

And as always, more auroras in Sweden (http://spaceweathergallery.com/indiv_up ... _id=152915)

The GOES X-ray flux shows continual decreased activity from AR2738, which is now flaring in the higher A range with only an occasional low B-class solar flare.

Belgium' Royal Observatory issued this comment for today:

COMMENT: Over the past 24 hours solar activity has been low. The largest
flare was a B5.6 class flare. Active Region (AR) 2738 (Mcintosh class:Hhx;
Mag. type:Alpha) has been most active, producing several B-class flares,
including the B5.6 class flare, which peaked at 14:00 UT (08-Apr-2019).
Former AR 2737 is near the west solar limb, and has shown little activity.
No significant filament channels have been seen on the solar disk. No Earth
directed Coronal Mass Ejections (CMEs) have been detected. There are no
significant low latitude coronal holes on the solar disk. The greater than
10MeV proton flux remained at background levels over the past 24 hours.
Solar activity is expected to remain low over the next 24 hours with a
reasonable chance of a C-class flare from AR 2738.

The solar wind speed has fluctuated between 380 and 480 km/s over the past
24 hours. The total magnetic field strength has fluctuated around 5.0 nT.
The Bz component has been mainly negative, ranging between -7 and +5 nT.
Geomagnetic conditions ranged between Kp index 2-4 (NOAA) and local K index
2-3 (Dourbes) over the past 24 hours. Geomagnetic conditions are expected
to be quiet to unsettled.
TODAY'S ESTIMATED ISN : 012, BASED ON 19 STATIONS.

[Maria]

Latest comment from the Royal Observatory in Belgium:
AR2738 now has Beta magnetic configuration.

COMMENT: Over the past 24 hours solar activity has been low. The largest
flare was a B2.0 class flare. Active Region (AR) 2738 (Mcintosh class:Cho;
Mag. type:Beta) has been most active, the region has shown some evidence of
flux emergence and cancellation in HMI magnetogram observations, this may
increase flaring activity. Former AR 2737 has moved over the west solar
limb. No significant filament channels have been seen on the solar disk. No
Earth directed Coronal Mass Ejections (CMEs) have been detected. There are
no significant low latitude coronal holes on the solar disk. The greater
than 10MeV proton flux remained at background levels over the past 24
hours. Solar activity is expected to remain low over the next 24 hours with
a reasonable chance of a C-class flare from AR 2738.

The solar wind speed has fluctuated between 400 and 480 km/s over the past
24 hours, with a jump in speed experienced late on 09-Apr-2019. The total
magnetic field strength has fluctuated between 4 and 8 nT. The Bz component
has fluctuated around 0 nT, ranging between -8 and +7 nT. Geomagnetic
conditions ranged between Kp index 2-4 (NOAA) and local K index 1-3
(Dourbes) over the past 24 hours. The Kp 4 was produced this morning due to
a Bz of -8 nT and solar wind speeds reaching 480 km/s. Geomagnetic
conditions are expected to be quiet with periods of unsettled-to-active
conditions created by sporadic fluctuations in Bz and the solar wind speed.
TODAY'S ESTIMATED ISN : 014, BASED ON 24 STATIONS.

[Maria]

Below is the latest Comment from Belgium's Royal Observatory:

COMMENT: Over the past 24 hours solar activity has been low. The largest
flare was a B2.1 class flare (Although, a similar magnitude flare was
occurring at time of writing). Active Region (AR) 2738 (Mcintosh class:Cho;
Mag. type:Beta) has produced all the flaring activity, the region has shown
some evidence of flux emergence and cancellation in HMI magnetogram
observations, this may increase flaring activity. No significant filament
channels have been seen on the solar disk. However, there is evidence of a
back-sided filament eruption (STEREO-A Observations) near the south polar
coronal hole occurring around 14:30 UT. The eruption can be seen as a small
Coronal Mass Ejection (CME) emerging to the south-east of the solar disk,
in LASCO observations. The eruption is not expected to interact with the
Earth system. No Earth directed CMEs have been detected. There are no
significant low latitude coronal holes on the solar disk. The greater than
10MeV proton flux remained at background levels over the past 24 hours.
Solar activity is expected to remain low over the next 24 hours with a
reasonable chance of a C-class flare from AR 2738.

The solar wind speed has fluctuated between 410 and 460 km/s over the past
24 hours. The total magnetic field strength has fluctuated around 5 nT. The
Bz component has fluctuated around 0 nT, ranging between -5 and +4 nT.
Geomagnetic conditions ranged between Kp index 2-3 (NOAA) and local K index
1-3 (Dourbes) over the past 24 hours. Geomagnetic conditions are expected
to be quiet.
TODAY'S ESTIMATED ISN : 013, BASED ON 23 STATIONS.

On spaceweather.com, there are two articles dealing with this current solar minimum.
Check it out. at www.spaceweather.com

[Maria]

Here is today's comment from the Royal Observatory at Belgium:

Note that Beta AR2738 is gradually decaying. It now has an alpha magnetic configuration.
See the HMI solar image at: https://sdo.gsfc.nasa.gov/assets/img/la ... _HMIBC.jpg

COMMENT: Over the past 24 hours solar activity has been low. The largest
flare was a B2.1 class flare. Active Region (AR) 2738 (Mcintosh class:Hhx;
Mag. type:Alpha) has produced all the flaring activity, the region has
shown some evidence of flux emergence and cancellation in HMI magnetogram
observations, this may increase flaring activity. No significant filament
channels have been seen on the solar disk. No Earth directed CMEs have been
detected. There are no significant low latitude coronal holes on the solar
disk. The greater than 10MeV proton flux remained at background levels over
the past 24 hours. Solar activity is expected to remain low over the next
24 hours with a reasonable chance of a C-class flare from AR 2738.
The solar wind speed has fluctuated between 400 and 450 km/s over the past
24 hours. The total magnetic field strength has fluctuated around 5 nT. The
Bz component has fluctuated around 0 nT, ranging between -5 and +5 nT.
Geomagnetic conditions ranged between Kp index 1-3 (NOAA) and local K index
1-3 (Dourbes) over the past 24 hours. Geomagnetic conditions are expected
to be quiet.
TODAY'S ESTIMATED ISN : 015, BASED ON 17 STATIONS.

[Maria]

From www.spaceweather.com today, Saturday.

IS SUNSPOT AR2738 SPLITTING IN TWO? The primary core of sunspot AR2738 is divided by a brilliant canyon of light--also known as a "light bridge"--measuring some 20,000 km from end to end. Amateur astronomer Martin R. Wise photographed the phenomenon from his backyard observatory in Trenton, Florida. Follow the arrow:

"Great spots like these are awe inspiring, especially during solar minimum," says Wise, whose photo is remarkably detailed. The light bridge is only about 800 km wide--less than the width of the state of Texas. His image captures not only that narrow divide, but also hundreds of surrounding granules on the sun's boiling surface

The nature of light bridges is not fully understood. They often herald the break-up of a sunspot. Some research suggests that magnetic fields at the base of a light bridge are busy cross-crossing and reconnecting--the same explosive process that sparks solar flares. Does this mean sunspot AR2738 will explode--or quietly fall apart? No one can say. Readers with solar telescopes are encouraged to monitor developments.

[Maria]

:Issued: 2019 Apr 14 1645 UTC

COMMENT: Over the past 24 hours solar activity has been low. There have
been no significant flares. Active Region (AR) 2738 (Mcintosh class:Cho;
Mag. type:Beta) has been quiet, the region has shown some evidence of flux
emergence and cancellation in HMI magnetogram observations, this may
increase flaring activity. No significant filament channels have been seen
on the solar disk. No Earth directed CMEs have been detected. The greater-
than 10MeV proton flux remained at background levels over the past 24
hours. Solar activity is expected to remain low over the next 24 hours with
a reasonable chance of a C-class flare from AR 2738.
The solar wind speed has decreased from 425 to 375 km/s over the past 24
hours. The total magnetic field strength has fluctuated around 3 nT. The Bz
component has fluctuated around 0 nT, ranging between -2 and +3 nT.
Geomagnetic conditions ranged between Kp index 0-2 (NOAA) and local K index
1-3 (Dourbes) over the past 24 hours. Geomagnetic conditions are expected
to be quiet.
TODAY'S ESTIMATED ISN : 014, BASED ON 21 STATIONS.

[Maria]

Breaking news from http://www.spaceweather.com

A NEW SUNSPOT: A new sunspot is growing in the sun's northern hemisphere. Provisionally numbered AR2739, the bipolar region has a magnetic polarity that identifies it as a member of old Solar Cycle 24. Old-cycle sunspots rarely produce strong flares, so the chance of flares remains low even as the sunspot number increases with the emergence of AR2739.

This active region is trailing AR2738, which are both approaching the Western Limb where they will soon depart for perhaps another 13 to 14 day transit around the back side of the sun.

Below is the latest comment from Belgium's Royal Observatory:

COMMENT: Solar activity was at very low levels. There are currently two
sunspot groups on the solar disk: active region NOAA 2738, and a small, not
yet numbered region located near N05W12 that started its development after
07UT. No earth-directed coronal mass ejections were observed over the last
24 hours. The greater than 10 MeV proton flux was at nominal values.

Solar activity is expected to remain at very low levels.

Solar wind speed gradually decreased from its initial 400 km/s to its
current values just below 350 km/s (DSCOVR). Bz varied between -3 and +3
nT. The interplanetary magnetic field remained predominantly directed
towards the Sun (negative sector). Quiet geomagnetic conditions were
observed.

Quiet geomagnetic conditions are expected to continue, with a small chance
on an isolated unsettled interval.

TODAY'S ESTIMATED ISN : 012, BASED ON 15 STATIONS.