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Andy WilsonKeymaster
Thank 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/10871/137743Andy WilsonKeymasterI 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.Andy WilsonKeymasterHi 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,
AndyAndy WilsonKeymasterMany thanks to WOLAS. The local society I joined many decades ago when my interest in astronomy began.
AndyAndy WilsonKeymasterThe ‘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,
AndyAndy WilsonKeymasterMany 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,
Andy- This reply was modified 2 months ago by Andy Wilson.
- This reply was modified 2 months ago by Andy Wilson.
Andy WilsonKeymasterMany 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,
Andy- This reply was modified 2 months ago by Andy Wilson.
Andy WilsonKeymasterHi 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)- This reply was modified 2 months, 1 week ago by Andy Wilson.
3 August 2024 at 5:05 pm in reply to: Need help with instrumental response for low-res spectroscopy #624070Andy WilsonKeymasterI 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
- This reply was modified 3 months, 3 weeks ago by Andy Wilson.
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Andy WilsonKeymasterHave 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
Andy WilsonKeymasterThe problem has now been fixed. Members should now be able to edit their posts.
AndyAndy WilsonKeymasterGary 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.
AndyAndy WilsonKeymasterI 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.
AndyAndy WilsonKeymasterHi 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
Andy WilsonKeymasterGrrr. 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
Andy WilsonKeymasterHi Ian,
In that case I would not bother. At this time, other BAA Exoplanet observers are just submitting to Exoclock.
Exoclock was not in existence when I made the amendments to allow the BAA Photometry Database to accept Exoplanet observations. As I understand it, the Exoclock project has plans in place to keep the data publicly available for at least 50 years. I’m not involved in Exoclock so I can’t guarantee this, but it appears they have a solid approach to data retention and accessibility.
Cheers,
AndyAndy WilsonKeymasterHi Ian,
If you can easily do it then yes. It can be useful to have it in more than one database to ensure longevity of the data. However, Exoclock is what matters, as the master database for this data.
The difficulty you may find is converting the output from HOPS into one of the file formats used by the BAA. If that is difficult, then don’t bother.
We have some Exoplanet data in the photometry database. This was uploaded a few years ago, prior to Exoclock.
Best wishes,
Andy Wilson, BAA Photometry Database Manager4 July 2024 at 9:30 am in reply to: How to make a correction to observations submitted to the BAAVSS Database? #623653Andy WilsonKeymasterIan, thanks for pointing Max in the right direction.
As far as possible the webpages are designed so users can edit and delete observations themselves. There can be occasions where a more complex edit/delete is needed, and I can help with those.
Andy
BAAVSS Database SecretaryAndy WilsonKeymasterHi Giovanni,
I know from my work with the BAA Office that there have been significant problems with posting the Journal to some European countries since the UK left the EU. I am almost certain that is what has been going on here, as several European members have been in contact with the BAA Office.
I suggest you contact the Office at the below link, or from the contact details on the back page of all the Journals.
https://britastro.org/home/about-us/contact-us
They can pass this information onto the Journal printing and mailing company. There may be something they can do. Ultimately, they can send replacement copies if needed, though those too have the risk of getting stuck in the post.
You should have a reply from the Office within a couple of days at most. So here post again if you don’t get a response and I can chase it up.
There is of course the online copy of the Journal, though many of us prefer a hard copy to read.
Best wishes,
AndyAndy WilsonKeymasterI see the June Journal has now been published, with the Newsletter announcing the Journal sent by Janice McClean this morning. You can see it on the website homepage or access it from the Publications menu, noting you have to be logged in to view the full Journal.
My hardcopy of the Journal often arrives a few days after it has been published on the website.
Best wishes,
Andy -
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