Tau-Herculids: Observing Report

In 1995 The comet 73P/Schwassmann-Wachmann suddenly increased in brightness and broke up. This event was unexpected and due to its orbit being close to Earth the possibility of a future encounter with its debris could result in a meteor shower. Joe Rao wrote one such paper back in 2020 and many of us meteor observers were interested in the conclusion we could see something in 2022. As the time drew closer many more articles like this one in EarthSky further fueled the anticipation that something might happen.

Fast forward to Saturday May 28th and I was facing a problem: the weather forecast looked poor for eastern Kansas. During the week before I was carefully watching the weather and the Clear Sky Chart(s) for my area. By Sunday it was clear the models were predicting accurately and my area would be cloudy. Monday the 30th was the latest and last model run I would check on the Clear Sky Charts. South-central Kansas looked good with no clouds forecast through 1AM. Fortunately I had been researching a destination and had a spot picked out.

Late Monday afternoon I headed down to Kingman Kansas, about 45 miles west of Wichita. Outside that town to the west is Kingman State Fishing Lake and Wildlife Area which has its own Clear Sky Chart. It took about 3 1/2 hours driving to end up at my chosen spot. Thirty minutes later I was setup and waiting to observer the Tau Herculid (TAH) meteor shower. It could be just one meteor or it could be much more.

Waiting for darkness. Two cameras and SQM meter ready to go.

As true darkness neared, before I was officially observing, I saw three TAH meteors. This was a good sign! Any other year that maybe what one would see all night out of this practically unknown meteor shower. Once astronomical darkness had started I was officially observing. The night sky was reasonably good with a lot of moisture and atmospheric extinction near the horizon. My overhead SQM readings averaged 6.4 visual limiting magnitude, certainly a decent location despite the light domes from nearby towns.

The meteor shower was good but there was not an epic outburst of meteors that could have been possible (but was unlikely). For the Tau Herculid meteor shower this was an exceptionally active night, an outburst. And that was the point of this adventure, on this night Earth passed through a stream of debris from a very recent comet breakup. The model predictions that we would encounter some material from the 1995 break up turned out to be correct.

My actual observing report is filed here at the IMO. I recorded a total of 32 TAH meteors that night. Its possible I under counted the TAH meteors as I was a bit uncertain in some cases as the radiant area seemed pretty large. Meteors most often had short trails but I was surprised how bright many were compared to what I expected. During my night out I had two cameras running and based on @JAtanackov’s suggestion I ran one camera with a narrower FOV lens than I normally use. This 50mm/f1.4 lens was stopped down to 1.8 and captured a number of Tau Herculid meteors that likely would not have shown up very well using my wider angle lens. A quick review of the 700+ images captured on that camera shows one very bright meteor with an interesting sequence of images which I will post later.