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I have recently joined the Variable Star section. I have successfully used ASTAP to create a valid format file for uploading (BAAVSS and AAVSO).
However, I also use AstroImageJ and I have struggled (so far) in using the BAA Photometry Spreadsheet 2.11 to convert the AIJ measurements table into the BAA required format.
The AIJ measurements file appears to be imported into the AIJ tab of BAA_Photometry_Spreadsheet_2.11.xlsm ok but the Calculation and Results tabs do not seem to want to update any details and leave the pre-existing WASP example data.
Some fields in the BAAVSS and AAVSO calculated tabs have data from my AIJ measurement table but most fields appear to have old WASP dataThe BAA VSS database manager, Andrew Wilson has been very helpful but suggested I reach out to the community
I wonder if there’s any members who are experienced in using AIJ with the BAA Photometry Spreadsheet who might be able to assist in a walk-through as I suspect I’m doing something fundamentally wrong (eg via a Zoom call or other method)?
Relevant files attached for info.
Many thanksIn reply to: Astrofest 2024
Hi Dominic, Amazing! I transferred to Alan Knapp’s group in 2002 (or thereabouts) in the twilight of my career with Philips, avoiding redundancy in the process. I eventually took redundancy and early retirement when what was left of the lab moved to Cambridge in 2008. A sad end to what was part of a prestigeous institution that was up there (almost) with Bell labs. I had many interesting projects and conference/business trips over the years since I joined, in 1973, what was then the Mullard Research Laboratory. My happiest time was through the 1980’s to early 90’s modelling silicon power devices, computing power was increasing according to Moore’s law and the models could therefore become more and more detailed so I’m very familiar with solving thousands of sparse profiled matrix equations. I still have the software to do this (if you’re interested). It can solve (in principle) via LU decomposition any number of equations in any number of dimensions to any level of “fill in” all the way up to a direct solver using various iteration methods developed in the 1980’s (conjugate gradients, bi-conjugate gradients etc). I posted some of my work on the “legacy page” of my website http://www.thewhightstuff.co.uk.
Back to spectroscopy: I think you are referring to the principle of detailed balance in your last reply and that is what I used to determine the Einstein B coefficients but they vary too strongly between the Balmer series lines to reproduce my measurements. They are also temperature independent whereas my measurements, over a number of stars, definitley show a temperature dependance hence the reasoning leading to my equation A.4.12. Another pleasing feature of my model is that all calculated internal parameters have believeable values, the impact parameter for pressure calculation is approximately 8 Bohr radii and photon cross-sections are of the order of 10 Bohr areas.
I suppose I am looking for someone who would look at my model and say “yes this is how a ball of gas in thermal equilibrium would look spectroscopically” or “no it isn’t because….”, whether it’s a good model of any particular star is a separate question though the Sun looks to be well modelled in it’s gross features. I realise this is a big imposition on anyone so if it is of interest to you please continue this discussion via my email address ken.whight@btinternet.com and if you still live in the South East or are attending Astrofest it would be great to meet up. if it’s not of interest then thank you very much for taking the trouble to comment.
Regards
Ken WhightIn reply to: Astrofest 2024
Hi Ken,
Interesting that you worked at Philips Research. Our paths may well have crossed in the early 2000s, when I did three summer internships at PRL. At the time I was torn between a career in astronomy versus joining Philips, but the decision was made for me when PRL closed down. Just in case the world wasn’t already small enough – I’m guessing you worked in Alan Knapp’s group? His wife taught me chemistry at school…
As you say – you can get a long way by assuming local thermal equilibrium. How far is an interestingly controversial question. Without any independent way of measuring the physical conditions and composition of a star, it’s hard to verify exactly how accurate models are.
It’s a very long time since I’ve looked at these kinds of calculation, but I think the jigsaw piece you’re missing is Kirchoff’s Law. From memory, this has the consequence that any plasma that is in equilibrium for the polychromatic case is also in equilibrium with regard to emission and absorption at every monochromatic wavelength of light. The result is that you never need to solve the polychromatic case. You solve the equilibrium equations monochromatically for every wavelength you’re interested in. As I recall, if you’re interested in solving for the equilibrium occupation probabilities of the quantum states, your monochromatic equations give you a bunch of (thousands of) simultaneous equations that you can solve with a big (sparse) matrix inversion operation. You should end up with something resembling a Boltzmann distribution.
The oscillator strengths reflect the fact that transitions are more likely between quantum mechanical states with similar wavefunctions – which give rise to strong lines – versus those with very dissimilar wavefunctions – which give rise to weak “forbidden” lines. But calculating wavefunctions is somewhere between difficult and impossible, and numerical approximation often don’t seem to resemble reality particularly well. Hence the tendency to use empirical lab measurements.
Best wishes,
Dominic
In reply to: map of light pollution trends
See a presentation on this at the 2018 joint BAA/AAVSO meeeting
https://britastro.org/event/baa-aavso-joint-meeting-on-variable-stars
Mario Motta – American Medical Association statement on street lighting
There could be a video of it somewhere on the website
In reply to: map of light pollution trends
I tried pointing out to the local lighting officer and my County Councillor that lower colour temperature LEDs were better, as they reduced scattered light in hazy/foggy conditions
You would probably have more success going on social media saying blue LED lighting causes cancer. (Unlike with 5G there is apparently some evidence to support this and has caused some towns in the US to rip out their recently installed blue LEDs in favour of lower temperature versions. See a presentation on this at the 2018 joint BAA/AAVSO meeeting). Failing this, pointing out the effect on wildlife might gain more traction among the general public, particularly if yo have any green councillors
In reply to: BAA song
OK, I’ve given this a go, and I found the words are extremely difficult to fit to the tune, especially the final line of each quatrain. The secret is to put the main stresses there on the B of ‘British’ and the A of ‘Association’. The final word has to be sung ‘As-so-ci-a-tion’, not, as printed in 1924, ‘Associ-a-ti-on’
To get a unified rendition of it, with a group, one would need to print up an accented copy of the words, similar to what church choirs use for singling psalms.
It would work best, exactly as the report says, with one person singing all the words, and the rest joining in only on the choruses consisting of repeats of the last pair of lines in each quatrain.
If people are serious about this, I’ll offer to conduct a rehearsal.
In reply to: BAA song
Everyone else would need ear protection if I were to join in.
Only dogs like my singing; they howl along with me.
In reply to: Roger Pickard
A great shock. Roger was a great help to me when I joined the VSS, never treating any of my novice requests as trivial. I have a treasured memory from some years ago when I came over from Australia and attended a Christmas meeting chaired by Roger as President. As proceedings got under way, to my amazement Roger gave me a formal welcome. How pleasantly surprised I was!
A sad loss. Roger will be greatly missed.
In reply to: Roger Pickard
I would like to thank Dr Shears for informing the VSS group of the passing of Roger Pickard. It is always sad when somebody reaches this time in their lives. Rodger helped me when I joined the section a few years ago and although I only met him on a few occasions he was a gentleman. Maybe Rodger wanted us to be informed in this way.
In reply to: IAU for amateur astronomers?
As mentioned by Martin, the IUAA had their General Assembly in Dublin in 1978. Also there, Patrick Moore gave a public lecture in the Mansion House. I remember it well, as this was my first time to attend an astronomical talk! I am afraid I cannot remember the actual title of Patrick’s talk. I did not attend the excellent IUAA event itself as I had not yet joined the IAS.
Quite a few of the IAS members were involved with the IUAA. My memory was that James Kelly, Ciaran Kilbride, Eamonn Ansbro & Vincent Deasy were the IAS representatives.
The IAUU had very laudable ambitions of setting up worldwide observing sections. However, one problem was they were overlapping (in part) with organisations like the BAA and the AAVSO etc which were already doing a good job.
John
In reply to: Scrapping Honorary Membership !
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?
In reply to: Scrapping Honorary Membership !
The complexity of administration that Andy alludes to is very much the point here, and very much in the thinking of the Working Group that recommended this package of changes, and also in the considerations of the Trustees and Council, who have discussed this several times in the last year. The income aspect is quite significant, as this is around 10% of the membership that is paying no subs, but also what needs to be considered is paying for the staff time to administer a complex system. That’s primarily what we are trying to grapple with. Also very apparent, as Andy mentioned, is the lack of volunteers, that means paid staff must do ever more tasks to run the Association.
Some have asked that we honour 50 discontinuous years of membership rather than only 50 continuous years. I cannot imagine how that could possibly work. Membership data over the years has been held on several different systems, manual and computerised. The current on-line database only goes back a few years. People who have lapsed then rejoined probably have multiple membership numbers. Marrying this information up, where people change numbers, addresses and even names, to prove whether someone has or has not subscribed to the BAA discontinuously for 50 years, would be an administrative nightmare. Maintaining the system we have is bad enough!
Though I can see how people who expected to reach honorary status soon might feel a bit disappointed, I must say I struggle to understand some of the solutions that have been proposed here. ‘Honorary’ means unpaid, free. That’s what the word means, and what we are considering here: whether or not to continue to give free membership to those who achieve 50 years continuous membership. Abolishing the honorary membership does not mean not honouring those members who reach this milestone, whether it be by publishing their names in the Journal, congratulating them in a meeting, or giving them a certificate or a badge (though I’m not sure if the cocoa thing was a joke or not).
I hope plenty of people come to the SGM in January. Last January only between 30 and 40 people attended the meeting, as I recall, about half of those, Council members. Not all Council members attend the London meetings, as some are in remote corners of the UK, but they can still participate and vote in Council meetings by Zoom. However, ordinary members cannot vote in a meeting remotely, they have to be present. This raises the possibility in my mind that a vote in Council could be overturned in the SGM by a smaller and less representative selection of the membership than voted in Council. This would be very unsatisfactory. But if plenty of people turn up to the SGM, there is no such issue.
In reply to: End of Schools’ eligibility to be Member Societies.
The plan is for the BAA to continue to have Affiliated Societies. However, they would not be a paid type of membership that receives the Journal.
Depending on how this is handled, this could open up Affiliated Societies status to more societies.
On a related topic, the BAA also has a library category of membership. Unless an individual joins to share the Journal, this might be a way to separate Affiliated Society status from paid membership while giving a route to receive the Journal.
In reply to: Scrapping Honorary Membership !
I, too, am not far off my 50th anniversary. Whilst it might have been nice to have a free membership, it does seem odd in this day and age that I should pay nothing, yet people just joining would pay the full rate. It seems neither fair nor necessary. This is especially the case considering the financial deficit that the Association has been running for many years (fortunately counteracted by the benevolence of former members who have left legacies).
The BAA has been a central and constant theme of my life. I’d like to think that if you cut me in half you would read the Association’s name running though me like a stick of rock. That for me is the honour.
I actually applied for membership at Christmas 1973 (where did those 50 years go?) and was elected in early 1974. However, I was an impecunious schoolboy so had to drop out for a couple of years, rejoining in 1978. So that is when my continuous membership starts. 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).
By all means bring the motion to continue Honorary Memberships – and thanks for starting such an engaging debate – but I won’t be supporting it. But I would support Gary’s proposal for free Horlicks at meetings!
In reply to: Scrapping Honorary Membership !
I am following the debate with interest and I can see both sides. (I joined in 1969 and so am now four years into my honorary membership.) As an honorary member and being overseas I gladly contribute 21 pounds per annum to continue to have a paper copies of publications mailed to me – but these mailings are out of pocket expenses for the BAA and do not contribute to the general running expenses.
Many years ago members could purchase a life membership by an upfront payment but this was discontinued because it became simply a wager as to how long you would last.
My feelings on attaining my 50 years standing was one of achievement, rather like my 65 years involvement with local clubs, my near 50 years observing and timing lunar occultations, and when I finally built it, my 44 year old observatory. I am still active and contribute to two sections of the BAA, one of them intermittently since the late 60’s/early 70’s. Now age 81, I certainly agree that with some luck and good management, retired people have the money to easily afford the membership fee and much more, but that is not the point. It is simply the recognition. Even your motoring clubs like RAC (here anyway) give out gold memberships after 50 years. (You just have to live long enough!)
To sum up, I feel it would be reasonable to honour this class of 50 year plus members, and even reward their loyalty by a reduction in membership fee – I think half fee was suggested, and this should cover the obvious administration expenses – and I am happy to also pay any extra postage as I presently do. Clearly we must cut our cloth to fit the current circumstances and I believe that with the internet, the residual effects of the Covid pandemic, and the the ready availability of you tube and zoom meetings, we have largely lost the comradarie that we once had when we could only reasonably pursue our interests by joining a club, attending meetings to listen and make friends, and borrow books from their library.
Our local club, much like the BAA is shrinking and only half the size it was in the early space age, composed of an ageing membership (very few under 50 years old), with key individuals engaged in their own narrow fields of interest as I am. Having some mobility problems myself I have attended meetings by zoom only in recent years.
I can’t see that it will be getting any better. Same goes for the club instruments available for loan – no-one seems interested any more. Instant gratification by the internet is so quick and easy.
Even my wife of 56 years is not helping. When in a moment of candour (maybe being a bit pompous), I said to her that I would like to leave something behind in the field – she said ‘You mean like a cow?’ I was puzzled until she added “Well it leaves something behind in the field too.’
So I think we should rely on BAA council to come up with a solution to honour our long standing members but not have the shifting demographics place an unfair burden on the rest of the association. As for obtaining new and younger members might I suggest an earlier British tradition called ‘Press Ganging’?In reply to: Scrapping Honorary Membership !
Concerning the ageing demographics, I note that this problem is not exclusive to the BAA or to astronomical societies, but it is visible in most membership societies operating on traditional models, across all activities and hobbies. The young generation is much less interested in joining societies than the immediate post-war generations were. They get their information and social interactions in different ways.
We have a Diversity Working Group which is looking at the whole issue of what the BAA should do to broaden its appeal – not just to young people, but (the bigger issue really) to women, and to minorities. It will report to Council shortly, and hopefully some suggestions will get taken forward and do some good.
Young persons’ membership rates are already less than half the full rates, and I’m not convinced offering free memberships would get us more participation from young people.
However we remain a democratic organisation, and if someone wished to propose (and someone else second) such a proposal at the SGM, it would be voted on, and the Trustees and Council would be bound by the result. Similarly, someone could propose that we continue to give the free membership to those with 50 years’ continuous membership, and, if the meeting so voted, we would.
David Arditti
PresidentIn reply to: Scrapping Honorary Membership !
I and a number of my contemporaries joined the BAA in our teenage years or our 20s, then as impoverished students our memberships lapsed until when in our 30s or later we had more spare time for our hobby and could afford the annual subscription. None of us are eligible for Honorary Membership and I guess that 50 continuous years will become a rarity.
Proposals to support younger members – and retain them – are welcomed.
Alex.
In reply to: Scrapping Honorary Membership !
I am some way off the ‘bus pass’ membership though it is a small future incentive when I have looked at options for my membership.
I’m not a member of a local society but many BAA members are. What strategies do they use for increasing younger/active participation?
The joining page doesn’t list 26 categories and I’m surprised there are so many. I propose maybe three payment rates even if many categories.
Why not let the ‘benefactor’ membership bed in for a year or so before making even more changes?In reply to: Scrapping Honorary Membership !
Being only two years away from my 50 year membership of the BAA I am left feeling a little deflated by this anouncement of the scrapping of honorary membership by the Trustees. It is not the subscription money that I would have saved if my membership became honorary and therefore free, but it will be the lost feeling of pride and achievement that missing out on the award of an honorary membership by the Association that I have been proud to have belonged to for most of my adult life. Also I look back at the list of previous honorary members and I would have felt an extra pride that I would have joined their ranks. The sending of a certificate will not engender that same feeling of pride. I will not stop being a member of the BAA, my intention is to remain a member for the rest of my life. Now I suppose, looking forward, my main achievement may be to have an obituary published in the JBAA! I have been an active member of the BAA for almost 50 years and have participated in most of the BAA’S activities and contributed to its publications over those years. I was not asked about this decision before it was made,perhaps a rethink my be appropriate before it is sanctioned and ratified. Perhaps it is right that we recognise members who have been supportive of the BAA for so long. We are not a Association who are bereft of funds, both currently and going forward so why can’t we honour our long standing members in this way. I would be happy to send my membership fee to the BAA as a benefactor after being awarded an honorary membership.It is the recognition, by the Association, of long participation and continuous membership that is important to me not the free membership.
Denis BuczynskiIn reply to: New membership categories
I’ll try to answer this.
We are proposing removing affiliated societies as a category of membership. Thereafter they will not pay anything to the BAA, and will not receive the publications. However, we anticipate that many societies will still wish to be affiliated because they wish to be associated with the name of the BAA, and will view it as a mark of their standing or credibility. Council would only approve the affiliation of properly-constituted societies.
The members of affiliated societies would still be welcome at BAA meetings. For meetings where there is a ticket fee, it is possible we could continue to offer lower prices to affiliated society members than to the general public, but that will be decided on a case-by-case basis. We’d be free to offer other benefits to them not yet decided. I hope we would give affiliated societies publicity on our website and in the Journal. I think Section Directors would still be happy to give advice to members of affiliated societies (though speaking as Director of the E&T Section, it is my policy to give more time to people whom I know have subscribed to the BAA individually).
What Bill says about the Journal distributed through a local society is interesting. Most societies I know have abandoned maintaining a lending library, and, if affiliated, they don’t really know what to do with the Journal and Handbook, they are typically just kept by the Secretary. It would of course be possible for an official of the society to join in his or her own name, get refunded by the society, and donate the publications to the society – which is the same as happens now, but using different words.
David Arditti
President
British Astronomical Association
Supporting amateur astronomers since 1890
