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Hi Marc,
It is great to see how spectroscopy has grown at the BAA over the past couple of years. The subject being one of the main areas of discussion on the forum, with advice being given to help members get started, as well as some fantastic results being shared.
We also have a spectroscopy database where members can upload their 1D fits format files. Noting a separate login is needed as it runs on different software to the main BAA webpages.
I think Ernst’s proposal for a VV Cep campaign is great. Though I am aware that Ernst has a long running campaign on VV Cep and so I am not sure if it is appropriate to think of it as a BAA campaign. There is a separate thread that Ernst has started on the campaign so probably best to post any questions there so that there is a single place to access the information.
Sadly for me a bank holiday weekend when I actually have time to do some spectroscopy and the forecast is for wall to wall cloud! Oh well, as a UK based amateur astronomer I learned along time ago that large reserves of patience are essential 😉
Best wishes,
Andy
Hi Ernst,
Thanks for the information which is useful to know. I’ll try to get an observing session in soon on VV Cep. If that doesn’t work out then I may use my limited observing time on Be stars which are well suited to an occasional spectrum when time allows.
Best wishes,
Andy
Welcome to the BAA Marc and great to have another spectroscopist! As you have no doubt seen, the spectroscopy forum has been very active.
Andy
That is an interesting campaign Ernst.
I’d like to get involved if I can, though my own observing has been significantly curtailed this year due to other commitments. If things settle down over the Spring/Summer then I’ll add it to my target list so that I can contribute.
Best wishes,
Andy
I concur that it was a great weekend, many thanks to Ann Davies, Alan Dowdell, Roger Pickard, and everyone else who were involved in the organisation.
Tough to pick out the best speaker, but I was very impressed by Prof Giles Hammond stepping in for the Gravitational Waves talk, you really could not tell that he stepped in for someone else. I also enjoyed Dr Poshak Gandhi’s talk on black holes as he engaged with the audience and did not simply use PowerPoint. Lots of other great talks but I won’t list them all.
Andy
Hi Tony,
There is no need to re-classify your objects. I did this as part of the checks that I run, though if you do ever spot anything that should be changed then just let me know.
Just look for the new subtypes when uploading spectra, and also let me know if you need any new ones setting up.
Cheers,
Andy
Hi Nick,
I think you mean the ALPY guide module rather than a separate off axis guider. Though that doesn’t really matter for this discussion.
I assume that you are using the ATIK Titan for guiding. When you say no response, does it take an image which is blank, or can you not even get it to take any image with the Titan? I take it you are pointing your setup at the blank daytime sky for the solar spectrum. Note it should not be pointed at the Sun for a solar spectrum as the reflected light from the sky is easily bright enough. Pointing directly at the Sun would probably fry the guide camera and might do some other damage.
Otherwise you could try other software rather than MaxIm DL for guiding. Though I use MaxIm DL to acquire my spectrum images, I switched to the free PHD2 for guiding as I found it far superior.
Best wishes,
Andy
Hi Kevin,
That is a nice looking spectrum and an interesting story to go with it. A good example that you can get unexpected results with spectroscopy and by digging around in the literature lots of useful and interesting information can be found.
You are getting some great results with your ALPY.
Cheers,
Andy
Hi Tony,
In ISIS (and other amateur packages) this is usually taken account for in the single combined step for instrument and atmospheric response correction.
The approach is take a spectrum of a standard A or B type star that has a spectrum in the Miles or similar database, and that it is at a similar altitude to your target. You use your spectrum along with the one from the Miles database to calculate a combined instrumental and atmospheric response correction. Where this won’t work is if you try to observe a target at a significantly different altitude, or if the sky conditions change. In that case you would need to take a fresh spectrum of an appropriate A or B type star.
When removing individual atmospheric telluric lines then it will be necessary to take a more sophisticated approach. ISIS has another tool which can be used for that but often this step is not needed for the target spectra. I also find this only approximately works rather than giving a really good telluric removal.
Cheers,
Andy
Hi Alun,
As David says, this spectrum would be a welcome addition the BAA Spectroscopy Database, and expect you have others.
The spectra need to be in 1D fits format with the BeSS fields populated. I know BASS can produce this format, so just let me know if you need any pointers. Otherwise just email me a sample 1D fits file when you are ready and I will use that to set you up in the database. I don’t put my personal email address online, but you can email me at vssdbm <at> britastro.org
Cheers,
Andy
That is a nice image for 400 seconds. I will be interested to hear how you get on with that project.
Cheers,
Andy
Hi Alun,
M87 could be a very interesting target. I have no idea whether the features, like the plume or jet, are within reach of our spectroscopes. If they are then the results would be fascinating. The central black hole might show broad emission lines due to fast rotating gas, while a jet might show a big blueshift.
Cheers,
Andy
Hi Alun,
Your reminded me of when I took a spectra of M81 and M82. Like you I was just interested to see what I could see in spectra of galaxies. My setup is for high resolution spectra, so it is very hard to go faint and I just see a small region of the spectrum. M81 was almost entirely noise, while M82 though noisy did have some interesting features I could investigate.
Below are the spectrum and the view through my guide camera. It turns out I had placed the slit on some known HII regions called regions A and D. This allowed me to do a radial velocity calculation that showed a redshift of about 255 km/s.
It is nice to sometimes take a spectrum of an object without preconceptions. Then you can experience the joy of discovery, even if many others have been there before.
Cheers,
Andy
Hi Peter,
This is a fantastic discovery, a system with 7 Earth sized planets! I expect we will learn some of the real science behind this discovery and the future research of this system at the Winchester Weekend. Prof Didier Queloz is giving the Alfred Curtis Memorial Lecture, and he is one of the authors of the Nature paper announcing this latest discovery. Brilliant timing by the meeting organiser!
I agree the media tends to get carried away, and social media even more so. It is a shame as I think the hype can miss the excitement that we do not know everything yet. So there will be lots of discoveries along the way as we learn about this planetary system and others which are no doubt waiting to be discovered.
Cheers,
Andy
Hi Alun,
That is an interesting spectrum. The hydrogen emission lines that you have picked up will be from HII regions within NGC 2903. Doing a little digging around I see that this galaxy has a high star formation rate. So it makes sense that it has a lot of bright clouds of hydrogen which will be forming stars.
Best wishes,
Andy
Hi Tony,
I’ve submitted a few observations to BeSS.
The good news is that the file format is identical to the BAA Spectroscopy Database format. They in fact came up with the format, and we used it as it makes sense to have one format across the different databases.
You can download spectra from the BeSS website, and on the registration screen there is a tool you can use to check your file.
http://basebe.obspm.fr/basebe/Accueil.php
The administrators are very friendly and knowledgeable, but note they can sometimes take a few weeks to respond.
Cheers,
Andy
Hi Paul,
That sounds like it would be an excellent setup for variable star observing. Some BAA observers have started to use Muniwin for variable star photometry as it produces output files in the format for upload into the BAA VSS database.
http://www.softpedia.com/get/Science-CAD/MuniWin.shtml
As well as looking at the VSS website it is worth dropping Roger an email line if you would like to start variable star observing. The section is very active and we are always keen for new members. Of course this forum is also ideal for any questions as there are other people can look at the answers.
Best wishes,
Andy (BAA VSS Database Secretary)
Hi Jack,
That error message indicates that crucial FITS header fields are missing. First out I would double check that it is definitely a FITS file which MaxIm DL created, as I know it can save multiple file types. Otherwise I think something odd that has gone on with your bias, dark and flat processing.
Cheers,
Andy
