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We are now 3 months into the HR Lyr campaign and we have a nice light curve of this old nova developing. This can be seen on the VSS website. It has been brightening steadily over the last 3 weeks and is now as bright has it has been for a very long while. It will be interesting to see just how bright it becomes.
Time-resolved photometry continues to show various humps and bumps in the light curve with an amplitude of ~0.15 mag. These appear to be fairly regular for a few cycles (~1.5 h), but they do not appear to be consistent. Moreover the shape of the bumps is quite variable.
A couple of requests:
1. Please keep the once-or twice per night snapshot photometry going. New observers are always welcome, of course.
2. Some really long photometry runs (several hours) over a few nights would help us to understand the short term variations and see whether a coherent signal emerges. Late July onwards would be a good time for this as the nights are becoming longer.
Many thanks to all the observers who have supply visual and CCD photometry:
David Boyd, Walter Cooney, Pavol Dubovsky, Sjoerd Dufoer, Carlo Gualdoni, Kevin Hills, Steve Johnston, Mel Joslin, Paul Leyland, JH Mallett, Ian Miller, Ken Menzies, Martin Mobberley, Roger Pickard, Gary Poyner, Jeremy Shears, Dave Smith, Richard Sabo, Tonny Vanmunster, Ivan Walton
Jeremy Shears
Good to hear you might be able to attend, Eric.
I’m staying in the conference hotel in Grimbergen the Friday and Saturday nights. Which is probably just as well since Grimbergen is well-known for its Trappist beers.
I wonder if anyone else is going from the UK.
Several hours, Grant, probably > 3 (there is a proposed period of 0.1 day, which could set the lower limit for t/series, but I’m doubtful about that). However, such long runs are not possible at these latitudes atm.
We are now one month into the campaign and, whilst it’s still early days, it’s good to see the first data coming in. Many thanks to: David Boyd, Walter Cooney, Sjoerd Dufoer, Ian Miller, Ken Menzies, Martin Mobberley, Roger Pickard and Gary Poyner.
The star has varied between mag 15.4 and 16.2. Time series photometry by Roger Pickard and Ken Menzies has shown various humps and bumps in the light curve, but it’s too early to determine if they are periodic.
With Lyra becoming more accessible in the evening sky, I hope that further observations will begin to flow in. Do feel to join in the campaign. We are looking for nightly snapshot photometry to determine the overall shape of the light curve and well as some multi-hour photometry runs to look for short-term periodicities.
Further details about the campaign can be found here.
Yes, I’m following it from my home observatory, Mike. I had it at mag 14.2 in an unfiltered CCD image last night (Apr 25 at 21.04 UT).
Looks like I’m in for a few cloudy nights, so I hope you are able to be more successful from Arizona
Glad to hear Alan’s talk went down well and to see him looking so well. Wonderful to hear his experiences of a lifetime in astronomy – I’m looking forward to the video.
Thanks Bill. David Portree tells me we can expect some more images of the crater:
“Stand by on that new Blagg crater image – tentative date is 4/25. We have the low-Sun image mosaic I used in the post and some high-Sun images that show mainly brightness variations – if all goes well, the new image (actually a pair taken on successive orbits) will be intermediate between the two, so we’ll see more of the Blagg crater floor and more secondary crater wall slump action (if it exists).”
If I hear more, I’ll let you know.
Lunar occultations could be an interesting project, especially to observe grazing occultations where several members of the AS could be spaced across/along the graze track. Could even be extended to asteroidal occultations.
Many thanks for the reminder, David.
I have now registered for the conference.
I would be interested to learn if any other members will be travelling to the meeting.
I have updated the light curve of this star today and it is available on the VSS website.
In the 3 months of the campaign we have caught 11 of its small outbursts. There is a suggestion that they are stunted outbursts, similar to those seen in some novalike cataclysmic variables, including UU Aqr, in which only a part of the accretion disc goes into outburst.
There is also a curious larger-than-normal fade around JD 2458520 (this was present in data from several observers).
Many thanks to all out observers, the list of which has been growing steadily: Richard Sabo, Ken Menzies, Gary Poyner, David Boyd, Dave Smith, Ian Miller, David Storey, Sjoerd Dufoer, Martin Mobberley, James Boardman, George Fleming, Mel Joslin, William Kautter, Erik Schwendeman, Tamas Tordai and Mario Morales Aimar. Your data have provided a well-sample light curve which I am sure will yield useful results!
The campaign was intended to last 3 months until the end of 2019 Feb, i.e. today. Thus will the campaign is officially ended, observations would also be appreciated after this time. Since this is a circumpolar object and continues to be well positioned for most northern observers. We would like one (or a few) observations per night to define the overall outburst light curve and whether there is a quiescence period between outbursts. In the meantime I will analyse the data received to date.
A summary of what is known about the star and about the campaign is presented in the March edition of the BAA Variable Star Section Circular (page 15) which was issued today.
That’s a really interesting and encouraging observation, David.
i see there is a report on observing the Pup in S&T this month and the author was successful with a 130 mm refractor, although I presume from a more southerly latitude.
Owen,
I’ve used Park-and-Ride facilities in York on a number of occasions and they are very good.
Jeremy
my residence is in a designated conservation area and hence I needed planning permission for my 2.1 Pulsar observatory. Note the house itself is not listed – it is a contemporary construction.
Before I submitted my application I spoke to the planning department and also to neighbours. The main concern was that the obsy should not be visually obtrusive. the planning officer asked whether the building would be white or silver as that might cause problems. I indicated that a number of colours were available including green.
When the approval came through, the only stipulation was that the fibreglass must be green! I considered this to be a result. Since this colour was also favoured by my wife, I was able to proceed.
Very nice work Bill. Your initial experiments show that this is a very promising development. It will be interesting to see how a more sophisticated grating performs with the ZWO camera.
An updated light curve is available on the VSS website.
There is a paper on this impact on ArXiv
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