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We should indeed be making it more affordable for young people to join. In fact I wrote to the President at the time to suggestion a lower rate for young people, but it was many years before it came to pass. Which is why I proposed a motion at the 2023 SGM, seconded by Nick James, not to increase the young person’s membership rate (as reported in the current Journal).
I was present at 2023 SGM when we voted not to increase the young person’s membership rate and I thought that this was a good thing at the time. Now with the proposed changes to the by-laws we, as membership, will not be able to do this and it is something that also worries me. I know that often not many people turn up to vote at these SGMs but I am sure if a rate change was contentious enough people would attend.
As far as honorary memberships go it seem to me that it looks a bit like fiddling at the edges of a bigger problem to do with the future survival of the BAA. Unless it becomes a financial burden I don’t see that this should be changed out of hand just because it appears as low hanging fruit. Perhaps the BAA needs to face up to larger structural problems. What is the major issue at stake? Is it that it can’t survive longterm on the money it raises through membership? Is it that membership will eventually decline because of its age profile? Is it that it is becoming too large to manage all the things it currently does?
I went out at about 11.30pm last night as the fog had lifted but I can confirm that I didn’t see a single meteor during the 20 mins or so that I stood in the garden. The moon was well up by then which may have hidden fainter ones. I also went out Friday night for about half an hour around 7pm but I only saw one sporadic.
I am slightly at a loss to understand why there hasn’t been much comment on here from the Aurora section about what we saw on Sunday night. From what I have read STEVEs are a relatively new phenomenon which haven’t been well observed and aren’t well understood. I have seen people say that they are difficult to see, but this one wasn’t. It was as clear as a bell and wasn’t limited to either the east or west horizon. It went in a clear arc from the eastern horizon to the western horizon in a continuous band. What is more, each termination at the horizon was associated with a red display of auroral (?) light both east and west. Added to this it appeared to flow from east to west (and never the reverse) with bands moving along its arc. I was surprised that my pictures on the gallery seemed to generate little interest. I uploaded them pretty much as they came out of the camera so the scientific value of them wouldn’t be lost by making alterations.
This article gives some explanation of what a STEVE is https://www.livescience.com/mysterious-aurora-like-phenomenon-steve-appears-during-strongest-solar-storm-for-more-than-half-a-decade.
My latest post has disappeared again due to over editing!! What a nuisance. What I said was that thanks to Grant I think this white arc was a STEVE. I made the point that the red glow in the east to the right of the arc was mirrored in the west by a similar red glow (an aurora?). Also I have calculated that the arc reached a maximum of 60 degrees altitude due north rather than 70 degrees. Further, I would be interested to know if anyone else has seen the fast moving “curtains” travelling along the arc from east to west. They can be best described as bands which were perpendicular to the direction of the arc.
The display seems to have subsided now (20:00 UT) but I just wanted to jot down what I saw whilst it is fresh in my memory. I am in a semi rural location near the Norfolk Broads. Probably about 18:35 I went outside to look at the sky and there was an arc of milky light running almost due east to due west which I thought at first was cloud. I went to grab my camera and the first image I took was at about 18:42. This showed it was definitely an aurora. The arc ran through Perseus in the east, then probably up to 70 degrees above the northern horizon then down to the west. It was quite well defined. Above it in the east near the horizon was a red glow that showed up well in an image. What was really interesting was that as the arc strengthened in intensity curtains of light travelled along the arc from east to west. I was surprised at how quickly they were travelling. I would say that they covered about 15 degrees of arc in a few seconds.
This is only the second big display I have ever seen so my technical knowledge of how to describe it is poor. The arc dissipated about 18:45 and then returned again to the same strength. I took photos until about 19:10. A bit after that I could see some reddish glow due north (my dinner was ready so I had to go in!). Pictures to follow.
Hi David. I didn’t need to be logged in to read this pdf via this link, so I guess it is visible to non members too. Don’t know if this is an issue. Duncan.
Thanks Alex and David. I can see now it is obvious in the pdf version of the journal but it wasn’t very obvious in the printed version. Looking in better light I can now see it but it eluded me this morning. It seemed a bit like a “where’s Wally”. Tonally, it blended into the background or perhaps it is just me.
This star has now returned to its normal range of magnitudes. There is a paper that has appeared in the Astronomical Journal (https://iopscience.iop.org/article/10.3847/1538-3881/ace59d) where the authors have imaged the star during the great dimming using interferometry. They say that they saw an asymmetry in the stars photosphere which suggests a mass ejection of material. This would have cooled and formed a dust cloud that dimmed the star. This is similar to what happened to Betelgeuse in 2020.
Thanks very much for your detailed news item about the comet. I did try to find it Sunday morning but even though we have had some “clear skies” we have been plagued by hazy conditions and there was too much murk near the horizon to make it possible to view anything. I will try again, weather permitting, when it moves round to the evening sky in a few days time.
That’s a pretty amazing picture and a fantastic tail only marred by the curse of the satellite trail.
Thanks Nick. I did see this other forum post but I missed the detail about it remaining close to the sun. When I first read it I thought it was a discussion about visual comet finders versus automated surveys. I think it would be useful to have a specific news item that just describes what is going on with this comet in slightly more layman’s terms. Clearly some people are getting good pictures of it but it means getting up an hour before twilight?
I think it is annoying that this comet is getting heralded in the press as yet another comet for the general public to see but it sounds like it is anything but easy to follow.
I was very sorry to miss this meeting but I had a prior engagement that would have been difficult to break. I hope to join you all another time!
I was pleased to see that Z UMa has been highlighted in a recent facebook post. I have added the light curve of this variable star from this post below. As described, in the last year the maxima have become nicely double peaked and it has been suggested that this is due to the interaction of the two main periods of pulsation of this star. However, how does this square with the analysis of John Greaves that after 1995 there is little evidence for two pulsation periods in the data (see my earlier posts on this topic)?
I wondered if the timescales for the evolution of the double peak fit in with the two periods of 194.0 and 204.8 days that John measured before 1995. If you imagine that the two pulsation periods start out in phase, then after one period of each the peak of the 194.0 day pulsation will be ahead of the 204.8 day pulsation by 204.8 – 194.0 = 10.8 days. After n such periods, the shorter pulsation would be ahead by n x 10.8 days. Looking at the light curve for the star you can see that for the last double peak (September 2022 to November 2022) the two humps were separated by about 3 months or roughly 60 days. This would seem to imply that the two periods would have been in phase n = 60/10.8 ~ 6 periods earlier and this certainly seems feasible looking at the light curve.
So how often would we expect double peaks to be occurring if the two periods of 194.0 and 204.8 days persist? The simple linear addition of two sine curves of the same amplitude but different periods of A and B would result in another sine curve of period 2AB/(A+B) which in this case would be 199.3 days but the amplitude of this would be modulated by a cosine curve of 2AB/(A-B) which is 7,358 days or about 20 years. However, a cosine curve passes through zero twice every period, so the “beat” frequency is half this, i.e. every 10 years. This is only a very rough guide because I am sure that the behaviour is not linear but it seems reasonable given what I said in my earlier posts about how often double peaks occur. Interestingly, the amplitude of the light curve variations does decrease as a double hump approaches.
What is says to me is that we really need more accurate measurements of the light curve to better see what is going on. Have the two pulsation periods begun to die out as John says or are they being hidden in the noise of the data? Perhaps we need regular digital detector monitoring over the next 20 or 30 years to decide this. Anyone fancy this?
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