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Hi David,
I have just approved one of the posts and deleted the duplicate.
It is difficult to know why it was classed as spam, but it could be to do with the “provided funds” text, given all the requests for funds scams out there. Though if this post gets approved then perhaps not..
Best wishes,
AndyHi Gordon,
There are no silly questions 🙂
For those who have joined in the past few years, your subscription becomes due on the day of the year you joined. For those who joined many years ago, the annual subscription always ran from 1st August to 31st July the next year.
Reminder emails are sent to every member who has provided an email address, about 95% of members. Those who have not given an email address are sent letters. The reminder emails are sent before the renewal is due, then several after payment was due if the member has not renewed.
Gordon, you can login to SheepCRM to see your renewal date. If you are not logged into the BAA website then click:
Login -> Renew Membership
If you are logged into the BAA website then:
Account -> My membership
You use the same password that you use for the BAA website but you have to login separately to SheepCRM.
I won’t give out specific details on the forum, but Gordon’s subscription is not due for a few months.
Best wishes,
Andy (BAA Systems Manager)The meeting recording has now gone live on the BAA YouTube channel. If you watch it directly on YouTube then you will be able to jump to each of the talks using the time links in the event description.
https://youtu.be/9vNO2gI3RVA
Unfortunately the slides are not properly displayed on the recording until 15 minutes into the meeting. We were hoping to have this fixed but unfortunately it has not proved to be possible.
Best wishes,
AndyHi Ian,
I am glad that did the trick.
Yes, there is no way you can tell that is from two telescopes. Shows excellent agreement between the setups.
Cheers,
AndyIt is a bit hidden away. When you are logged in, navigate to the forum home page. Next to create new message is personal messages.
https://britastro.org/community/forum/personal-messages
It can also be a little tricky to find some people depending on the name they have used.
Making this more accessible and easy to use, is on the list of things to do to the website.
Andy
Hi Ian,
I have implemented a change to the BAA Photometry Database that should resolve this problem.
The upload now checks the Julian date, object, observer id, filter (visual observations are automatically recorded as no filter), location and instrument.
This does mean it is just a little easier to upload duplicate observations, especially as the instrument and location are free format fields. However, it should be rare that someone comes back to upload observations at a later date but with very slightly different entries for these fields.
I should add that while I have tested this for a variety of scenarios, I can’t check all possible scenarios. Hopefully it won’t cause problems for other observers. There is a chance it has slowed down the upload processing, but hopefully any impact will not be noticeable.
One final thought. For an observation to be flagged as a duplicate, the Julian dates must be coincident in time to better than a tenth of a second. That is certainly possible, but I thought I’d mention it as my expectation would be for a few seconds or tenths of seconds between the timing of images with different setups, with just a few occasions where they agree to better than a tenth of a second.
Best wishes,
AndyHi Ian,
Yes, I manage the BAA Photometry Database. You can contact me here and also at my email address.
When I created the online database I did not foresee a single observer submitting observations of the same star in the same filter made at the same time from different locations or telescopes. The previous offline database had a problem with duplicated and even multiple sets of the same observations, so it seemed a good idea to prevent duplicates being added. I have heard of this doing the job correctly in the past but this is the first time for this scenario where it creates a problem.
I will need to give this a little bit of thought and remind myself of the precise details of the database and the code that performs the checks. The location and telescope were not historically populated for all data. They were designed as descriptive fields and are not built into the checks to prevent duplicates. It may be possible to make a tweak, so one or both of these are included in future checks but I need to spend a little time checking into this before implementing any changes.
There is a simple fix, which is to provide you with two observer codes and logins. The observer logins are tied to a single observer code, and the observer code is one of the key fields used by the duplicate check. This would not be as neat a solution, as it would split your observations into two observers. So it is probably worth giving this a few days as I may be able to easily make a change to the duplicate check.
Best wishes,
AndyI suspect the drop in the blue magnitude is due to the material cooling as the ejecta of the supernova expands. Taking a first approximation of a black body, then the shorter frequency blue light will reduce first as the explosion cools. You can see the effect in Robin’s spectra animation from a few days ago.
With the caveat that I am not an expert on supernova, so someone else may be able to jump in to confirm or refute this notion.
AndyApologies to Nick, I accidentally deleted his light curve of SN 2023ixf. Now added back after Nick sent me a copy.
As an admin I have delete and detach links, next to the link to view attachments. I must have hit one of those when trying to view his light curve.
It is great seeing all the photometry and spectroscopy of this supernova.
Andy
Hi,
How do you calculate its magnitude please ?Hi Kwong,
A variety of software packages can do photometry, including some image processing packages such as MaxIm DL. If the software you are already using doesn’t have the ability to calculate magnitudes, then I would opt for a free package that is easy to use, unless you are sure you will get into photometry of variable stars, exoplanets or asteroids.
There is a list of some software packages at the top of this page on submitting to the BAA Photometry database.
https://britastro.org/vssdb/notes_submissions.php
I’ve not tried them all, but MuniPack might be the easiest to get started with.
The trick is you have to measure the magnitude of the target star (the supernova) as well as several comparison stars. The comparison stars need to be carefully chosen, to avoid variable stars and to ensure they themselves have a robust magnitude. The AAVSO chart plotter is the perfect place for this.
The other key point. The supernova and none of the comparison stars must be over exposed as that would cause the calculation to go wrong. A good rule of thumb is for the peak counts in any pixel of those stars should be at most 2/3rds the full well capacity of your camera.
Good luck with your observations.
Andy (BAA Variable Star Section Database Secretary)
Here is a link to the AAVSO chart. For those who haven’t used them before you can adjust the size and orientation by clicking plot other chart, and access the magnitudes of the labelled comparison stars by clicking photometry table for this chart.
https://app.aavso.org/vsp/chart/?star=SN%202023ixf&fov=60&maglimit=14.5&resolution=150&north=up&east=left
AndyI saw it visually through a 10-inch last night and it was very obvious. I estimated it at magnitude 11.8. I don’t consider myself a seasoned visual observer so being close to a V magnitude of 12 sounds about right.
AndyHi Paul,
I have sent you an email where I have included the BAA Office who manage the donations.
At present we use Square to take donations. The same service we use for the BAA shop and telephone payments. I have tested the donation page just now and it was working on Chrome, Firefox, MS Edge and Safari, running on Windows 11 and macOS Ventura. I wonder if it was a temporary glitch or whether something in your browser might be blocking the Square site, link below.
https://checkout.square.site/merchant/MLW65481JK36P/checkout/SL5VCCR2YENEZGEKFZPD6AGH
Best wishes,
AndyI have received confirmation from the venue that they successfully made the recordings, apart from a problem with the slides not being recorded at the start. They are hoping to be able to fix this. They need to get everything together and make some edits, with an expected timeframe of a week or two before they are with us to add to the BAA YouTube channel.
AndyHi Paul,
Yes, you are missing something.
If we loaded the AAVSO data at a point in time, it would slowly become out of date. This would then generate errors rather than warnings for those charts during observation uploads. When you provide a chart recognised by the BAA database, it then checks the comparison stars match, their magnitudes, and checks the photometry calculation. So adding data that becomes out of date would cause bigger problems than just accepting a warning message.
The whole point of the charts in the BAA database is to allow checks and recalculations. As the AAVSO use numbered comparison stars based on the magnitude, this means star 102 in a chart at one point in time, can be replaced by a different star later. That would corrupt the calculations giving incorrect results. I would not implement a system that I know would give incorrect results under realistic scenarios.
It is much simpler to accept the explanation that you can ignore the chart warning if you don’t expect the chart to be present, as per the user guide for the database.
https://britastro.org/photdb/help/WarningAndErrorInvestigation_UserGuide.htm
Best wishes,
AndyHi Paul,
Sorry this is causing you hassle. The point is these ‘warning’ messages are very useful to a large number of our observers. A ‘warning’ simply means ‘can you take a quick look at this to make sure it is expected’. It allows you to proceed with adding the data as only the observer has the knowledge of whether to expect a recognised chart or the other warning messages that are generated. When the upload generates an ‘error’ message then that means something is wrong and it won’t let the upload proceed.
We do have some AAVSO charts in the database. These tend to be older charts before they implemented their latest chart system, or charts created at a specific point in time. When I created the database I had discussions with the AAVSO about getting a copy of their chart data to add to our database. The problem is their charts are not static. A chart ID is not guaranteed to generate the same chart when entered at a later date, as any changes to the AAVSO chart database will result in the same ID giving a slightly different chart.
The chart is particularly important to the visual observers as the BAA database can recalculate magnitudes to the latest sequence. It can actually do that for digital as well as visual observations where sufficient information is provided, though we currently only have it turned on for visual observations.
As a final note, I would point out the AAVSO charts are fantastic and used by many BAA observers. It is just the BAA database cannot use them for more detailed processing as their chart IDs do not uniquely identify the comparison stars and their magnitudes.
Best wishes,
AndyHi Paul,
I successfully use a Quark Chromosphere with a Williams Optics 66 and 81mm refractors for visual observing. I use a UV/IR filter.
While this works, it isn’t quite a quick grab and go setup as I have to wait for the Quark to reach the right temperature and sometimes tweak it to get the view at its best.
Best wishes,
AndyHi Paul,
I believe these charts are designed for use by visual observers. There the simplicity of a single decimal place is beneficial to the visual observer.
Cheers,
AndyFor those who are going, I have added some information about car parking sent to me by Hazel Collett.
https://britastro.org/event/baa-spring-meeting
Best wishes,
Andy
