The Dutch Observatory

One Active Region….three days …. in three wavelengths.
Three days in the evolution of AR2759.

Shown are close ups of AR2759 on April 2nd, April 3rd, and April 4th in Ha, 540nm and CaK.  The horizontal comparison shows the evolution over the three days shown in the images, whereas the vertical comparison shows the difference we see in different wavelengths.  On the first day when the area measured 20 millionths and was a D-class area, the 540nm and CaK image are enlarged a bit, but one can see the faint faculae in 540nm how they pretty much follow the patterns of the plages in the other wavelengths. Interesting to see the penumbra in the 540nm image on the 2nd at the southern outside of the two larger spots, whereas the center spot is devoid of any penumbra. Also pretty obvious how much the spots have deteriorated on the last day. And lastly, it shows how my CaK scope’s optics are affected by corrosion in need for resurfacing.

A late session today but clear skies.  AR2759 has deteriorated quite a bit.  I missed it in WL for the first observation, but got it the second time around.  Two leading spots and one following.  The plages are still nicely to see in CaK and Ha.  Full disk images today as well as close ups in the three wavelengths.

Another beautiful day with clear and perfect skies. AR2759 has increased to 30 millionths but looks a little more compact.  Today full disk images as well as close ups of AR2759 in the three wavelengths and the prominence in the SE in Ha.

A Short Summary of CR2228

Carrington Rotation CR2228 covered the time period from 2020-03-01 0126 UT – 2020-03-28 0857 UT.

For two days on March 9th and the 10th, the rotation did bring a new active region AR2758. On March 9th as an Hrx, and 10th as a Cro area, however, its size did not exceed 20 millionths.  I did not have the time to keep up with the Reverse Polarized Areas during this rotation, but will catch up for the next summary with a new reverse polarized area report. On March 28rd the current spotless streak stands at 18 spotless days.   Overall Solar Activity remained Very Low and the rotation increased the spotless days count since solar maximum to 716 days. Finally, during the period SWPC reported three A-class, one B class and no C-class flares.

Wow, clear skies from horizon to horizon!  And the area which I imaged on the 30th with a few pores has developed in a nice D-class Active Region AR2759 measuring 20 millionths.  Today not only full disk images but also close ups of the region in three wavelengths and a very nice prominence at the South Eastern limb in Ha.

A short window of clear skies between lots of clouds.  A new area has appeared near the NE limb showing up as a faculae in WL and plages in Ha and CaK.  I observed two small pores.  The area has not been named, so we’ll see if they develop in a sunspot.  Today full disk images as well as close ups of the mentioned area.

Another spotless Sun.  Day 17 in the current spotless streak.

The skies cleared up and showed another spotless Sun today, with some nice proms at the NE, NW and SW limbs.  Full disk images today in the three wavelengths.

A sunny day with some high cirrus clouds and contrails.  Another spotless day for spotless day 707 since Solar Max.  A few faculae can be seen in the Eastern hemisphere and some prominences can be seen in the NE, E, and SW.  Otherwise the sun looks quiet.  Today full disk images in the three wavelengths.

Clear skies today with below average seeing, and SWPC reported a spotless Sun.  However we can see something developing not far from the SE limb.  Initially as a plage in CaK, and a pore in 540nm which might become a sunspot.  But so far it has not been named.  In addition we see some nice prominences around the NE and NW limbs.  In the meantime we have surpassed the 33 day spotless streak which ended a year ago on March 5th 2019.  SILSO calls the current streak the longest spotless streak of the current minimum. However, SWPC recorded 2 longer streaks.  One of 36 days and the longest of 43 days.  These however, are still way below the 44, 51 and 52 days in the previous minimum.