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It was fantastic to see Michael Woodman in person, and really great that many members of his family were able to attend the presentation of his Butterworth Award.
While it is a shame not to have consistency, I think in general it is a good policy to give Observing Sections as much autonomy as possible. The Observing Sections are the heart of the BAA, and are run by experts in their field doing world class observing and research.
The Variable Star Section is a good example of why it can be useful to make a Circular public. I know that professional astronomers read it. If it were behind a pay wall then that might not happen. Having the professional researchers read the Circular benefits the members who contribute to the Section.Hi Nick,
You need to be logged into the website to download the Solar Section Newsletters. I suspect that if you login then that will solve the problem.
https://britastro.org/document_folder/baa-document-store/sections/solar-section
Best wishes,
AndyI have a 250mm Mewlon. To solve a problem with condensation on the main mirror, I wrap a dew heater band around the back of the scope, near the main mirror cell. During the winter months I leave it on constantly at a low level, turning it off before observing. I have found this works well at preventing any moisture from forming on the optical surfaces or within the telescope tube. It only uses a tiny amount of power.
I also have a tube heater, something like 60W or 80W, set on a timer in the winter. This gives just a little heat to the observatory, but did not stop condensation within the optical tube.
I have a wooden roll off roof observatory.
AndyHi Paul,
With a Digital Subscription you receive everything digitally, including the Handbook. The difference in price between Digital and Paper subscriptions is the cost of printing a posting both the Journals and the Handbook.
Here is the link to the Handbook archive.
https://britastro.org/document_folder/baa-document-store/the-baa-archives/baa-handbooksBest wishes,
AndyThank you all!
I have received official notification of the award of my PhD, after the minor corrections to my thesis were accepted.
I don’t expect anyone to read it, but I thought I would use this opportunity to provide a link to my thesis at the University of Exeter online portal http://hdl.handle.net/10871/137743I think a coalition of organisations with a shared interest in reducing light pollution is an excellent idea. While the CfDS could campaign purely on astronomical grounds, this won’t be important to many people and politicians. Joining forces with others who see the problems of light pollution from other perspectives will strengthen the case for change.
There is no mention of involvement with ‘climate activist’ groups or anything that is likely to be picked up by media as activism. I think you would find the majority of wildlife campaign groups go about their activities in a law abiding way, trying to engage with people rather than causing confrontation. That is certainly how our local wildlife group goes about their work. In fact we had a talk on light pollution this week.Hi Gordon,
I know what you mean, lugging a heavy telescope outside can put me off observing.
Assuming you are using your Televue for visual observing, I wonder if an altazimuth mount would be lighter? You can get manual or ones that track sufficiently for visual observing. Some of the tripods themselves can still be a little heavy, though the whole package should be lighter than an equatorial mount.
The latest smart telescopes look very interesting. I am contemplating buying one of the lighter models. Of course the observing experience will be different. They specialise in Deep Sky targets and none are good for planets. Most can observe the Moon and Sun, though only the full disc.
Best wishes,
AndyMany thanks to WOLAS. The local society I joined many decades ago when my interest in astronomy began.
AndyThe ‘explainable’ bit means it is not a black box. With many kinds of machine learning, you don’t know the precise details of how the input data are transformed into the outputs. I used naive Bayes, which is basically maths. So you can trace the output back through the calculations to the inputs. This means the results can be explained and fully understand in terms of the input data. For my research it means I can understand why a particular object was classed as a young star, or as some other kind of object.
Thanks,
AndyMany thanks for all of the kind words.
Yes, this means I will become a ‘professional astronomer’, a three year position as a ‘Postdoctoral Research Fellow in Astrophysics’. Early career astronomy researchers typically work at a variety of institutions or countries on two to three year contracts with specific research goals.
My research will involve examining spectra taken by the William Herschel Telescope. The main part of my PhD was identifying candidate young stars, using photometry in the optical and infrared. The WHT will obtain follow up spectra for several thousand of these candidate young stars. These spectra will allow me to confirm or refute their nature as young stars.
Best wishes,
AndyMany thanks.
The experience of doing photometry and spectroscopy, learning from fellow BAA members has been invaluable. Both helping with my application to do a PhD, and when it came to analysing observational data. The knowledge I gained from being a member of the Variable Star Section has been especially beneficial to my research into young stars. They are highly variable, and some other types of variable star can share observational features with young stars, so a broad knowledge has been very useful.
I am fortunate to have a 3 year postdoc in star formation starting next month. Then I will switch from being a part-time to a full-time researcher.
Best wishes,
AndyHi Mike,
The team is composed of very experienced spectroscopists active on the spectroscopy forums, so they probably knew of the nova about the same time as Jeremy. Collaborations tend to be by BAA members on observing campaigns and other projects. In fact many of our spectroscopists are active across a variety of international projects.
Cheers,
Andy (with my BAA Spectroscopy Database Manager hat on)I thought I would jump in with an example of how reddening affect can affect a spectrum. This is a spectrum of Brun 818. It is a B6 star behind the Orion nebula. It suffers from about 6.5 magnitudes of reddening in V, causing the slope of the spectrum in the optical to change direction!
To use such a star for response correction is tough. You either need a response corrected spectrum someone else has made, or you have to carefully deredden the spectrum.
If you have a good Miles spectrum that has not been dereddened, then this kind of scenario should be OK. Though with high reddening values you may end up with only a weak signal at the blue end.
On another topic that came up. When selecting the binning region for a spectrum, I stretch the image to make the full top and bottom edges of the spectrum visible. I then set the edge of the spectrum bin to include all of the signal, even the weak parts, while trying not to include any unnecessary background. I suspect this makes little difference, but if you set the binning region too narrow, then there is always a chance this will have a weird affect on the spectrum as you will be cutting out some of the signal.
Andy
Attachments:
Have you looked inside the spectrograph? Given both frames are giving weird results, it makes me wonder if something has been knocked out of alignment.
Another clue could be that bright line in the flat, and the odd short offset calibration lines, both appear at the same vertical offset. That could indicate something seriously out of alignment or light leaking in from outside.
Andy
Gary reported the same problem with the missing edit button. I have reported it to the website developer.
There was a change made on Monday to allow quicker edits, so I wonder if that caused an unexpected problem.
AndyI was very sorry to hear of the passing of Wil Tirion. I still own his wonderful Sky Atlas 2000.0 and Uranometria 2000.0. These were both beautifully presented and very practical. I would look over fields in the day, then take them out to the telescope at night.
Even today with modern planetarium software, I regularly use his Cambridge Star Atlas.
A great loss.
AndyHi Paul,
Is there a good reason why the expiry time is so ludicrously small? Other fora I frequent generally allow somewhere between five minutes and an hour. Long enough to spot speeling misteaks or to add an extra sentence of explanation, but not so long that it seriously distorts any historical perspective.
I think you misunderstood.
You can edit a post for up to something like 10 hours after you originally post it. There is another setting that prevents rapid editing of posts. A standard security measure within the forum, I think to prevent issues in case anyone’s account gets hacked, though this is not an area I have much involvement in. This had originally been set to 10 seconds, which is a bit too long. The website developer has amended this to 2 seconds. So anyone trying to edit within 2 seconds of clicking submit will find it won’t work. If they wait between 2 seconds and 10 hours they will be able to edit their post.
Andy
Grrr. Why can’t we edit posts for at least a short time after posting?
There is a protection measure that was preventing editing within 10 seconds. The website developer has now reduced this to 2 seconds.
Andy
