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Yes, I did think of trying SOHO but also drew a blank so perhaps I was looking in the wrong place on their website. Thanks for giving me the correct link.
Thanks Alex. Seems I’ve had a bit of a blind spot as far as that image is concerned as I regularly look at Spaceweather but for some reason I just scrolled down looking for images while entirely failing to notice that of the Sun prominently displayed to the left! Doh!!
The possibility of me joining the Council in order to foster further debate on the matter has been suggested before but I am inherently against “single issue” candidates. One should wish to join the Council in order to further the development of the Association, not just to argue a specific point.
Yes, I would entirely agree that the issue is likely to be low down on anyone’s priority list (including mine!) but I do wonder whether the current system, with its tendency to generate pointless ballots, is in some way responsible for the low voting numbers. Some (such as myself) may not vote at all because they realise that parts of the election are un-necessary anyway and others might be put off by the way that the elections for Council members and Trustees interact, with the additional complication caused by elections whose outcome is a foregone conclusion only adding to the confusion.
And while the issue might be low-priority, surely it is such a simple thing to understand and correct that it should not need a Parliamentary Enquiry to quickly resolve?
I am utterly flabbergasted that the BAA Council should have voted to retain the current voting system, let alone by a large majority. Did the Council members actually understand what they were voting for? That is, in the case where the number of candidates for a post does not exceed the number of vacancies, to retain an utterly pointless ballot whose outcome is known in advance. Merely transferring the ballot online does not change this simple fact.
Frankly, words fail me.
As I have already responded, the lack of people coming forward is not the issue I am trying to deal with by my suggstion of not enforcing a ballot whose result is already known. Apart from the fact that fewer people offering to stand will almost certainly result in additional occasions where there are no more nominees than are required to exactly fill the posts up for election, the two are entirely separate. Persuading people to stand is a matter of advertising and persuasion whereas the removal of un-necessary ballots is a constitutional matter. Hopefully, a resolution to change the Constitution in this way can be presented to the next AGM (I assume this is the way to do it) and be voted through very rapidly as it is surely simply common sense to not require an essentially pointless exercise.
It wasn’t the issue of cost that was the reason for my suggestion but rather the pointlessness of holding a ballot whose outcome is already known. The steady decrease in numbers of members putting themselves forward for offices and for Council is indeed worrying but is really an issue peripheral to my suggestion. I would be very happy to see ballots having to be held because so many nominations had been received but as that does not seem to be the case at present I still believe that my suggestion would be a worthwhile amendment to the Constitution, and maybe the corollary (to publish interim lists of nominees) might just encourage more people to put themselves forward when they see they might just have a sensible chance of being elected due to the low number of current nominations. Worth a try, surely?
I think you might have mis-understood my objection to the current situation James. I have absolutely no objection to anyone being nominated for any post or position, and I would agree with you that to have many nominations is eminently desirable for a number of reasons. However, once all nominations are in, if there are no more nominees than the number of posts of that type to be elected (i.e. one for officers, five for Trustee and five for non-Trustee Council Member) then those nominees should simply be deemed elected without further ado because that is going to be the outcome anyway. To ask the members to indulge in a ballot whose outcome is already certain does seem rather pointless. And I am certainly not suggesting any sort of “Buggins Turn” i.e. merely arranging for some favoured candidate to step into a post.
My suggestion does, of course, require an open and transparent nomination process, with the nominees published well in advance of the vote so members have an opportunity to nominate further persons (for any post) if they so wish. I may have missed such an announcement but I don’t think this is current practice, which may in some way suggest that “Buggins Turn” might be operating if, surprise surprise, there is only one nominee for a post when the voting forms come out.
I also entirely agree but felt I had to reply to what I believed was an overly political post by the previous contributor (now not visible). Maybe I should not have been dragged into doing so in an equally political way, but felt I could not let it go without comment.
The well-known and very popular program WinJUPOS might suit your needs. It will show any planet at its correct phase at any time & date, optionally with the unilluminated sector shown as well (in a darker colour), and one can then print or (more usefully) save the image for conversion into a template. It may be found at http://jupos.org/gh/download.htm
Delighted to hear it Giovanni! If there’s one thing we British excel at, it’s occasions like this. A superb display of precision ceremonial coupled with excellently played and sung music, setting off a majestic and solemn service.
Long Live King Charles and Queen Camilla!
Anyone who saw this week’s edition of the BBC series ‘Inside the Factory’ will have gained a little more insight into StarGazy Pie. For those who wish to educate themselves via iPlayer, the relevant section of the programme starts at the 17 minute mark. It would seem that, although the story about Tom Bawcock is almost certainly apochryphal, the Pie itself could well date back several centuries. Still doesn’t make it any more appetising though.
SteveH
And a Merry Christmas & Happy New Year to you also Alan!
I hope that the light you see over the coming week will be from not just stars & planets but also from twinkly illuminations, glowing candles, burning brandy on the plum pudding and the glow on the cheeks of family & friends! Just don’t start talking about all the photons flying about!!
With very best regards,
Steve
Hello yet again Alan,
The ultimate problem in understanding photons is that, as implied by Andrew and sort of stated in the Muthukrishnan paper, they don’t actually exist! Not as usually understood in explanations of optical phenomena, anyway. They are just one way of looking at light, which can be useful in some situations but not in others. In the end, as is also shown in the paper, everything depends on a) the maths and b) what you are trying to deduce from your observations. However, mere mortals who are not quantum physicists need models on which to base their understanding, so as long as you don’t think too hard about the ultimate nature of light and carefully pick the scenarios in which you use one or the other, the wave and particle (i.e. photon) models provide reasonable, if not exactly rigorous, explanations of such things as the excitation of molecules involved in retinal detection or photosynthesis. So don’t despair entirely!
But yes, as you say, often the closer you look the less definite things become – an example of the Heisenberg Uncertainty Principle!
Please do pass on anything I have said to your grandson. I believe it to be accurate at a “non-specialist” level so hopefully it won’t lead him down incorrect paths. However, I doubt whether a more detailed discussion than that in this forum thread would be considered appropriate as a Tutorial, as it is really in the realm of physics rather than astronomy.
As to the status of the observer in the observing process, I have read articles discussing the effect of variation of colour discrimination between observers on the observation of coloured binary stars but, as you say, little else. Still, now that most observations are done with electronic devices perhaps the poor old human observer will become a seriously endangered species!
Best regards,
Steve
Hello again Alan,
I put the quotation marks in because the word absorbed is usually employed in the sense of water being absorbed into a sponge, and that is not really what happens in the case of retinal stimulation or photosynthesis as it implies that the absorbed object stays within the absorber, albeit perhaps in some altered physical form. The danger here is in thinking of photons as objects, like little snooker balls. They in fact have no corporeal form, being merely packets of pure energy. When the amount of energy a photon carries matches the energy required to excite a molecule it encounters to a higher energy state the photon ceases to exist and the energy it carried is transferred to the molecule (all molecules vibrate and flex to some exent and the higher energy states correspond to modes of greater vibration or flexion). In its turn, the molecule can then pass on that energy to another molecule (dropping back to its original state as it does so) and so on. The end result of such a chain of transfers is often the production of a new molecule, the additional energy perhaps being used to overcome a repulsive force between constituent parts of the new molecule which would prevent that molecule being formed were it not for the intervention of the photon down the line.
Therefore, because a photon ceases to exist when it is “absorbed”, we do not embody every star etc. that we observe because the very act of seeing it destroys the photons coming from it. Again, the danger is to imagine photons as little balls which somehow lodge within us – not so! We do, of course, embody “star stuff” a different way, in that we are constructed from elements only produced in supernovae, but that is another subject entirely!
Steve
P.S. No, not involved in setting the Christmas Quiz but I am always open to being asked!
Hi Alan,
The simple answer is that the photons are “absorbed” by the process which stimulates the receptors in the retina. This process requires energy, which is supplied by the photons – which are basically just little packets of energy. In a similar way, photons incident upon a green leaf are absorbed by the chlorophyll molecules in the leaf to excite them to the higher energy level required to begin the cascade of processes involved in photosynthesis.
The reason the photons are able to travel through the eye without being absorbed is that quantum theory says they must be entirely absorbed, or not at all. For something to absorb a photon thus requires the absorber to have two energy levels separated by exactly the amount of energy contained within the photon. This is not true for the “interior substance” of the eye but is true for the retinal cells – something which evolution has honed throughout aeons. Moreover, because light of different colours corresponds to photons of different energies, discrete sets of retinal cells have evolved to respond to different energies/colours – hence our ability to see in colour. “Colour” is merely an artifact of our perception though – much like the false-colour renderings of the images from Hubble and JWST. Given this, different eyes see colour differently. Even within the human population increased sensitivity to both infra-red and ultra-violet light is not unknown. For example, evolution has given Schrodinger’s Cat greater sensitivity to low light, which is important for hunting at dusk, but a lesser sensitivity in the red. Assuming said Cat is actually alive, that is. Oh, sorry, I wasn’t supposed to mention said feline, was I? I promise no mention of singularities or higher-order infinities though.
Hope that is both non-PhD understandable and generally helpful!
Steve
Hi Andy,
Thanks for that. As the problem seems to be connected with the infamous spam folder, could you let me know where this is to be found please, and if a “release” can be actioned by a contributor rather than an administrator? That might at least enable the situation to be rescued even if the cause may not be clear.
Steve
Bad news! This is getting silly. Having spent quite a time typing a reply in the Partial Eclipse thread I tried to submit but it was refused as by this time the system had apparently logged me out. I thus logged in again and the Submit seemed to work but when I tried to do an edit my reply simply disappeared, as before, but the summary claimed the last reply was from me – true, but my reply was not listed. I thus tried yet again using the same text (saved as a precaution!) but then persistently got the error message “Deprecated: Function get_option was called with an argument that is deprecated since version 5.5.0! The “blacklist_keys” option key has been renamed to “disallowed_keys”. in /home/baaweb/baa_website_2021/britastro/wordpress/wp-includes/functions.php on line 5665″. At which point I gave up. What on earth is going on?
Steve
Well, after the saga of the disappearing edits and the successful outcome of my “Mars occultation” project, plus all the other diversions life throws at one, where were we? Ah yes – the problem of different diameters for Sun and Moon.
On which topic, I can but say “Yes, you are quite right”. I have to confess that I committed the cardinal error of looking for the answer before fully analysing the problem! The analyses of the general problem on the Internet all seem to take the centre-to-centre distance as the variable parameter rather than the chord distance, which does indeed result in some rather involved calculations – sometimes involving integration between limits! Conversely, using the chord distance and the w-sin(w) formula makes the extension to unequal diameters almost trivial, and I agree with your answer.
Using this principle in my spreadsheet, I also agree that the result for f=0.99253 is 18.08%. Interestingly, if I use the values 1201 and 845 for the Sun diameter and chord length respectively (instead of 1200 and 846) together with f=0.99253, the result is 17.955%, or a magnitude of 0.29093, compared to the online answer of 17.960% and 0.29098, which is exceedingly close and tends to confirm my estimate of “accurate to 1 pixel”. I am thus still happy with my result as it agrees with the online answer to within a variation of 1 pixel whether the online calculator used the f factor or not.
As to the operative limit of the formula, do you not mean “until w or W is GREATER THAN pi”? Fortunately, if f=1 this can never happen as when the angle is pi the event is an exact total eclipse and the formula gives the correct answer of 100% and 1.00 for the obscuration and magnitude. If f<1 the formula can indeed fail as we are then heading for an annular eclipse, for which the chord length actually decreases at some point and then becomes undefined during the annular phase of the eclipse. If f>1 the formula seems to give sensible answers until the chord length is equal to the Sun’s diameter i.e. the case which would be an exact total eclipse if f=1, after which it will give wrong answers becuase, as in the case of an annular eclipse, the chord length will decrease as the Moon moves further over the Sun’s disc. The formula will thus give reducing values of obscuration whereas it is of course increasing. Further analysis required, I think!
Steve
I had exactly the same problem as Duncan at the end of November, not once but twice. Both times, the edit was very soon after the initial submission. The first time, I realised I had attached the wrong file so hit “Edit” to see if I could change it but that simply caused the initial post to disappear. Having re-typed the reply and submitted it I then wanted to add some text so tried another edit but got the same result – a vanished post. Luckily, having been alerted to the problem the first time round, I had taken a copy of the text this time so could start again.
Steve
*** Tried an edit again. Seemed OK this time!
*** What “spam filter”, by the way?
