Monday, 1 January 2018 - 21:13 UTC
Happy new year everyone! Congratulations on surviving yet another trip around our Sun!
We had a slight uptick in the geomagnetic conditions earlier today as we hit active geomagnetic conditions (Kp4) caused by a short-lived coronal hole solar wind stream. The stream has since than become less intense and we are not expected to reach active geomagnetic conditions anymore in the foreseeable future.
Looking back at 2017, we must conclude that it was a year of the expected, and the unexpected. There were fewer solar flares (C or higher) than last year, fewer days with geomagnetic storm (G1+) conditions, more spotless days and of course a lower average sunspot number. Nothing strange as the Sun is becoming less active as it heads towards solar minimum.
This changed on 2 September.
That's when the unexpected happened. A very simple Alpha sunspot region with lucky number 2673 suddenly started to grow very rapidly releasing a string of M-class solar flares in the process. This activity combined with its incredibly complex magnetic layout got us hopeful. Will we get an X-class solar flare from this sunspot region, the first X-class solar flare since 2015? Yes, we got our X-class solar flare. Four of them in fact, and two of those X-class solar flares were the two strongest solar flares of the current solar cycle.
On 6 September, sunspot region 2673 released the strongest solar flare of solar cycle 24 (thus far... but good luck beating that) an X9.3 solar flare (X10 according to back-up GOES-13!) with an earth-directed coronal mass ejection. The coronal mass ejection arrival triggered one of the largest geomagnetic storms of the current solar cycle. The severe G4 geomagnetic storm threshold was reached on 8 September. Kp8 at 00:00-03:00 and Kp8+ at 12:00-15:00. DSCOVR solar wind and IMF data for that day can be found here.
While on the west limb, sunspot region 2673 left the disk with a spectacular X8.2 solar flare on 10 September that released a coronal mass ejection comparable to the X28+ solar flare of November 2003. The coronal mass ejection arrived as a weak shock at Earth.
For a complete overview of this period with intense solar activity we invite you to watch this YouTube video:
Sunspot region 2673 was responsible for 27 M-class solar flares, 4 X-class solar flares and a severe G4 geomagnetic storm. It produced the two strongest solar flares of Solar Cycle 24: X8.2 and X9.3.
Other than we had a fairly quiet year with over 100 spotless days and 52 days with G1 or higher geomagnetic storm conditions mainly due to coronal hole solar wind streams. We did not manage to reach the extreme G5 geomagnetic storm threshold this year but did had 2 days with moderate G3 geomagnetic storm conditions and 2 days with severe G4 geomagnetic storm conditions. That's better than last year as we did not had any geomagnetic storms that reached the G3 or G4 level in 2016 but 2016 had 60 total days where we hit geomagnetic storm (G1 or higher) levels.
For a list of the strongest solar flares this year check out this page. The strongest solar flares of this solar cycle can be found here. A list of the strongest geomagnetic storms of this year (ranked by the Ap-index) can be found here. All the graphs and data used as a source in this article can be found on our Solar Cycle progression page. Be sure to check it out!
It has been another amazing year for our website. We continued to grow and smashed pretty much any thinkable record despite the low solar activity. A huge thank you for the overwhelming amount of support in 2017 and we look forward to continue in 2018 which is possible for us due to the donations of the following people:
While SpaceWeatherLive is being run by just two persons, we did manage to add a lot of new stuff when we had the chance. Here is just a small selection of what we added this year:
We added ACE MAG/SWEPAM data since 1998 in the archive, a Russian translation and an acronyms and abbreviations help page just to name a few. Not to forget: this month we moved the website to a new server so we are ready for the future with up to date soft- and hardware.
In the beginning of 2018 we will also be launching an updated look for the website so keep your eyes peeled for that. This updated look will hopefully be followed by some other major changes later on in the year...
The entire SpaceWeatherLive team wishes you a fantastic 2018 and we thank all of our visitors for an amazing 2017!
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