There was both excitement and speculation caused by several CME's from Sunspot 3364 that were expected to hit Earth "sometime Friday".   Forecasts for aurorae are not extremely accurate, and timing can be off by several hours.  (CMEs travel outward from the Sun at speeds ranging from slower than 250 kilometers per second (km/s) to as fast as near 3000 km/s. The fastest Earth-directed CMEs can reach our planet in as little as 15-18 hours. Slower CMEs can take several days to arrive.)  The best news is that the odds were good that it might cause aurora to be seen low in the North in the St. Louis area and perhaps during our weekly "Friday Night Open House" event.  Luckily, our sky was forecasted to be very clear this evening.

The local and national news media were exciting the public.  We never know what that might do with our local population, but we decided to contact the County Parks department and ask for Ranger help with parking.  Good thing we had their help!  As the day went on the experts called for Kp 8 and G3 or higher.  Still, we expected that "IF" we saw aurora, it would only be seen 10* to 30* above the Northern horizon, and unfortunately, we had some big trees in the way.  There was no certainty that ANY aurorae would be seen.

I arrived a few minutes after 7PM and there were only about 5 of ourselves present.   By 7:30 we had a crowd of maybe 30 or so, all for normal viewing through telescopes.  Sunset was shortly after 8PM and the parking lot was now full, and more than half of the new arrivals were there to see aurora.  I called the Ranger hotline and Ranger Justin told me that he would be there just as soon as he finished closing gates on the other Broemmelsiek Park entrances (half hour after sunset).  In the meantime, a stream of cars needed to find parking.  I abandoned my telescope and started guiding the car parking effort on the mowed grass area on the East side of the entrance road for the next 20-30 minutes.  Around 9PM, Lisa Barnes asked me "Are those rays up there the aurora?".  I wanted to turn my head North, but she was pointing UP.  Sure enough, this aurora was BIG!  We were still in twilight, not fully dark yet, and I could see aurora 70* up!

I was stuck parking cars through about the first 15 minutes of the aurora, taking an occasional minute to call my wife and sister-in-law to have them look outside at their homes, and for me to take a very hurried shot with my iPhone 8. Justin arrived and took over parking.  I felt a little bad simply passing the baton as he probably needed help.  Heck, I wasn't about to miss out on this once in a lifetime event!  Our hand count of attendees stopped at 300 but estimates of 600 to 800 were probably more accurate.  This was NOT a publicized event at the park.  People in the area just know that Broemmelsiek Park is THE place to go to see celestial events!  Overflow watched from the Agronomy area parking lot, which Justin smartly left the gate open for.

The astronomy area was bizarre!  People simply gawking up in all directions.   All telescopes were idly standing by.  Although originating from the North, the aurora was all around us.  Rays were primarily in the North, but many anti-rays also seen due South.  Greenish "blobs" were seen past the zenith, often in the South but occasionally East and West.  The rays were gray and edged pink to my eye, but others claimed to see Red and Purple (rarest color) and of course camera images showed these colors much brighter and in detail.

Due to parking, I did not get a good 'start' time but many reported it was shortly before 9PM (the expectation was 10 or 10:30 start).  I had just seen aurora on my Alaskan cruise a week before, and I noticed back then that the newer phone cameras were picking up GREAT detail on aurora images and my old iPhone 8 showed very little (despite using the NightCap app).  I told myself that I needed to get a newer iPhone as soon as I got home - but little did I know that I would need it only 3 days after I got back!   I'll add that I did have my DSLR in the car, and I had recent practice using it on aurora (Alaska).  However, I was practically stuck in awe, dumbfounded that this was all around us and knowing it could end at any second.  Often by the time you picked an area of sky to point a phone camera, it was diminishing there while a brighter spot was appearing behind you!  I knew that others would get MUCH better images than I would, no matter what equipment I had, so I stayed put and enjoyed the show.

 It lasted strong until about 10:15 when it stalled and diminished until it was gone (actually just dimmed to local light pollution levels) around 10:30.  Only then did I start showing things in my telescope (Which seemed like a "booby prize" to those just arriving who had missed the big show!).

I continued to provide telescope views and answered the many questions of the late arrivals, with a tad bit of encouragement, until I packed out at midnight.  I would guess there were just under 100 still on site, with as many cars coming in (still!) as going out when I left.   The aurora did show up again later in the A.M. hours, but I don't know how many hung around there for it.

Every aurora is different, and this one was HUGE.  The final ratings were a Kp index of 9 and a G5, it was observed as far South as Puerto Rico and Hawaii!  Only the 3rd on record that far South, the others being in 1921 and 1859 (the Carrington Event).  Very rare indeed!  We are at a period of "Solar Maximum" (~11 year cycle), but a large CME needs to be fairly well "aimed" at Earth.  Unlike many great celestial events, our local Missouri weather bestowed clear skies for us to observe this wonder.

Jim Twellman

#Broemmelsiek Park