AR12755 from cycle 25 is still visible as an active region with sunspot but activity is declining, as the main spot can seen to be divided by a light bridge, which is a usual indicator of decay. This image is from the Solar Dynamics Observatory, but for amateurs it is still visible as a bright area in Hydrogen Alpha, and the plage will remain visible in CaK light for many days to come.
2020 is upon us, and as the world wakes to a new decade, we also wake up to a new sunspot from cycle 25, no sooner had AR12753 faded this new sunspot rounded the limb in the solar southern hemisphere. Given the southern hemisphere has this activity first, it will be interesting to see what the lag with the northern hemisphere following will be, this also leads to the likely possibility of cycle 25 being double peaked as cycle 24 was. This asymmetry on average could numerically result in solar cycles on paper being weaker, however if both hemispherical peaks coincided this would result in the solar cycle again being numerically stronger. We will have to see over the coming years as to how this all pans out.
This is my last solar image of the decade; clear skies on monday meant I was able to make the most of the small gaps in the trees to get a chance of seeing the sun. Cycle 25 active region AR12753 is still visible as a patch of bright plage, but all sunspots have now receded. A few small prominences and few ephemeral bright points are the only other things visible but as we move into 2020 activity is set to rise. This image was taken with the Lunt50 etalon on the ED60 f6 scope, double stacked with a Daystar Quark, a Baader solar telecompressor was used along with the PGR camera.
The information from Solen says it all; on Christmas day I was able to observe the 2 active regions visually using a Daystar Quark where they were easily visible. The chart above shows the magnetic signatures of cycle 25 are getting more prevalent. Poor weather is forecast for me for the rest of the year so unlikely I will get to image or view until 2020, either way next year should be an exciting time for all things solar!
Christmas Eve has brought not just one sunspot grouping from cycle 25, but two! We know this from their reversed polarity compared to cycle 24 spots. There have been a number of small single spots and pores earlier this year, but so far this is the most cycle 25 activity we have seen. Fingers crossed this is setting up 2020 as being a good year for solar astronomy as more features become visible.
published: Monday, December 09, 2019 22:30 UTC
The NOAA/NASA co-chaired, international panel to forecast Solar Cycle 25 released their latest forecast for Solar Cycle 25. The forecast consensus: a peak in July, 2025 (+/- 8 months), with a smoothed sunspot number (SSN) of 115. The panel agreed that Cycle 25 will be average in intensity and similar to Cycle 24.
Additionally, the panel concurred that solar minimum between Cycles 24 and 25 will occur in April, 2020 (+/- 6 months). If the solar minimum prediction is correct, this would make Solar Cycle 24 the 7th longest on record (11.4 years).
Monday was the transit of Mercury over the face of the sun, sadly I was at work at the time and observing it really wasn't an option unfortunately. Fortunately these days there are so many live sources of our star online that at various points I was able to get a virtual view of the transit. Here is the AIA1700 image from the Solar Dynamics Observatory I grabbed that shows Mercury as the small black disk nearly dead centre on the sun. The next doesn't occur until 2032, maybe I will be fortunate enough to have retired by then and will be able to observe it.
