PQ And in very rare outburst

Forums Variable Stars PQ And in very rare outburst

Viewing 20 posts - 21 through 40 (of 43 total)
  • Author
    Posts
  • #582541
    Gary Poyner
    Participant

    There is now a short and pretty basic PQ And page residing on the BAAVSS website   https://britastro.org/vss/PQAnd.htm

    Hopefully I’ll add to it as the outburst progresses, so if you have anything you’d like to share (spectrum, time series photometry etc.   I’m not asking for much am I) then please send it to me and I’ll add it.   

    And please don’t forget to add your observations of PQ And to the BAAVSS database

    Gary

    #582542
    Jeremy Shears
    Participant

    Good to see people overcoming the odds and securing successful observations of PQ And. I managed to see it this morning at about 02.25 BST. I decamped with my 12 cm refractor to a field a mile away and it’s far too low from my obsy as you can see from the angle of my telescope in the dawn sky.

    #582543
    Dr Paul Leyland
    Participant

    “this morning at about 14.25 BST.”

    I hope you mean 04:25 BST, or dawn comes remarkably late where you live 😉

    #582546
    Rob Januszewski
    Participant

    Obtained this rather ‘noisy’ image in the predawn sky, using a 102mm refractor mounted on top of my 10″ SCT.

    Rob Januszewski

    #582547
    Gary Poyner
    Participant

    Hello Rob,

    Good to see you’ve finally got to it after all these years!  Quite something isn’t it!

    Gary

    #582548
    Gary Poyner
    Participant

    Further to my #2 post above, our VSS director suggested I post a photo of my scope in PQ And mode.   Well here it is.  My trusty 30 year old battered 22cm dobby doing a balancing act on a table, but it does get me to view over the hedge.  I often do this for stars low in the north which my 51cm in the observatory can’t get at.  In the past it’s been on milk crates, house bricks etc. and even poked out of the bedroom window – much to my wifes’ disgust on a cold winters morning 🙂

    The cat didn’t show up this morning, so this is one I made earlier…

    Gary

    #582549
    Rob Januszewski
    Participant

    Hello Gary,

    Yes, great to catch a rare event like this. After 18 clear nights during May most of which have been exceptionally good quality I’m absolutely exhausted but just had to give it that extra half an hour to observe this.

    Rob

    #582550
    Nick James
    Participant

    That doesn’t look very stable Mr. Poyner. The cat looks to be a Brummie relative of bagpuss.

    #582551
    Gary Poyner
    Participant

    No it isn’t very stable Nick, but with careful handling it works fine – you just have to be patient!  Without it I wouldn’t have seen PQ And at all! 

    And if these pesky NLC’s keep away from Brum, I’m hopeful of continued use for a while longer yet!

    Bagpuss is a Brummie.  Thought everyone knew that.

    #582563
    Robin Leadbeater
    Participant

    OK  here are the spectra for 2020-05-29 and 30.   

    Apart from the hot continuum there is nothing common between them so unfortunately  the details are probably just noise. They were taken at 5 deg altitude (air mass 10) in a bright sky though so to be honest it was a surprise to get anything

    #582564
    Jeremy Shears
    Participant

    My goodness, Robin! You have certainly given this your best efforts. As you say, remarkable that you got anything given the circumstances!

    #582568
    Tim Haymes
    Participant

    PQ was at alt 8deg, and managed a sequence of FITS from 1.30 to 3 am BST.  BUT I dont know what to do with the data.    However i have a memamsured image giving a R mag of 10.5 using UCAC4. I dont know how one gets V mag with a filter. Where do you get the ensemble photometry data for V (or G)?   My image is attached (single image in Astrometrica).. I hope
    The browser is not playing ball.

    #582569
    Tim Haymes
    Participant

    Here goes. Ah! it seem to take a long time before its available to insert.   I may have made a second comment…sorry

    #582570
    Graeme Coates
    Participant

    Someone (ahem…) years ago decided to build the observatory due south of my wife’s office – not sure she’d be happy with a demolition job to have half a chance of an observation of this one! (I think even then, there’s a large ash tree that might get in the way!)

    #582572
    Jeremy Shears
    Participant

    Nice work, Tim! Looks like you solved your problem, but just to say I use V-band comparison star data from the AAVSO VSP. Comps for PQ And are listed here. If you used a V-filter on your camera (which I assume is monochrome?), the resulting mags are quoted as CCD-V. If unfiltered they would be CCD-CV.

    Thanks for tackling this star!

    #582573
    Jeremy Shears
    Participant

    I have poor horizons from my obsy, Graeme. But I’m lucky enough to have a second, portable, set up with an AZEQ6 mount which enables me to decamp to more favourable observing locations for special events like this.

    #582578
    Jeremy Shears
    Participant

    An Astronomer’s Telegram, ATel #13776, from the Kyoto group publishes a spectrum taken on June 2. This “showed Balmer absorption lines with emission cores, which are typically seen in dwarf nova outbursts. There are no signals of O III, which were reported in the 1988 outburst”, although they question the 1988 conclusion.

    #582581
    Robin Leadbeater
    Participant

    With the help of Thomas Bayes perhaps I can now claim to have previously detected both the Balmer H beta absorption with emission core and H alpha emission 😉

    My rectified spectrum from 2020-05-30 (red) overlaid on the spectrum published in the Atel

    (I also see the problem of not being able to insert images. I had to press “preview” before I got the “insert”  option)

    Robin

    #582592
    David Swan
    Participant

    This implicit reference to posterior probability in Bayesian statistics is just the sort of intellectual high-brow stuff one would expect on our forum 🙂

    #582689
    Gary Poyner
    Participant

    PQ And is undergoing it’s first rebrightening today after fading to 16.6CV on June 25.  Latest observations reveal 13.45V on June 26.45 (M. Mobberley).  This could be the first of several rebrightenings (or the only one), so please stick with it for the next few weeks if possible.

    The field is getting slightly easier in the morning sky now, so any observations made please report them to the VSS.

    Thanks and good luck,

    Gary

Viewing 20 posts - 21 through 40 (of 43 total)
  • You must be logged in to reply to this topic.