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It makes sense to me, and I understand your frustration at recording a <169 star when your nearly at 20, but the sequences for many stars are embedded into the DB, so if you report a negative value of <196 when the listed sequence ends at 169, then that observation might be rejected. Not all stars sequences are entered into the DB, and I’m not sure about SV Ari, but it might be. If it isn’t, and you enter <196 with a sequence code for a sequence which ends at 169, then that observation will be accepted but will cause some confusion when the data is looked at.
You might report such an observation with a different sequence number (one which you have designed yourself). This would then be flagged as an unknown sequence, but it would make it into the DB. Then in 20 years time or so when SV Ari wakes up again, you could monitor the outburst using the recognised sequence of the day – by which time the limit might be in the 20’s.
The less confusion in the DB, the better for all concerned.
Happy Christmas…
Gary
You should report the faintest star visible (recorded) which is measured on the sequence you are using. Adding fainter stars of your own means you are altering the official sequence, and the data might not be accepted into the VSSDB (depends on the object – I think).
If you wish to help extend the sequence to SV Ari beyond 169, then you should have a chat with Jeremy.
Gary
Is there a photograph of Birmingham anywhere? I mention him in my talk on historical novae, and always show his lunar crater as I can’t locate – anywhere – an image of the man himself.
Thanks,
Gary
I’d urge visual observers to add this object to their programme during this active, high brightness state if you can get through mag 15. I’ve been monitoring HR Lyr since the early 1990’s, and on June 29 this year I recorded it at 15.1 visual – the brightest I’ve ever seen it. Now is an excellent opportunity to actually see this historical Nova for yourself.
Gary
I saw the local midnight pass last night in Brum – by pure chance! Looked away from the eyepiece and there they were, appearing out of a bank of high cloud by CrB and heading over to Lyr. Impressive in Bins too. Several got very bright (+1.0 and brighter) . They appeared to come over in three waves. Quite a sight.
Gary
This snippet of info. was posted to VSNET today by Keisuke Isogai…
“The object faded to 16.4 mag on May 5. This object will (or has already)
show a long-term rebrightening with a duration of about 10 days. We will
be able to observe superhumps in the rebrightening phase. Because the
superhump period in the rebrightening may be different from that in the
main superoutburst, continuous observations are encouraged.”Gary
AL Com has dropped two magnitudes in just two days. I had a 16.3 estimate last night in a cloud break. Typical UGWZ behaviour. I wonder if it will pop back up?
Gary
Mike,
Your correct – there isn’t a lot out there on AL Com. There is this from 2001 which you might find interesting…
First detection of the growing humps at the rapidly rising stage of dwarf novae AL Com and WZ Sge Ishioka et al…
https://www.aanda.org/articles/aa/pdf/2002/03/aadj293.pdf
You will probably need to read up on UGSU or UGWZ stars to find a direct reference to AL Com. Taichi Kato et al has written a series of papers entitled “Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae” in which AL Com is included. I think there are currently nine papers in this series so far.
Hopefully the observations are being reported to the VSS database – although a look this morning suggests that some haven’t been uploaded yet. So far we have M. Joslin and myself visual and I. Miller, M. Mobberley and R. Pickard CCD – with Miller and Pickard reporting time series. I envisage a report on the outburst once it’s over appearing in a future VSS Circular.
Gary
I’m continuing to monitor it visually, and my last observation was Apr 25.98 UT at 14.2 so it’s fading gradually now.
Very probably the magnitude will drop quickly once it gets just below 15ish, but this might not be the end of the outburst. UGWZ stars very often (but not always) have ‘echo’ outbursts or rebrightenings. AL Com has a history of this. Since 1995, three of the outbursts detected have showed this phenomenon, but the 1995 one was the best. It was the first outburst of AL Com observed with the ‘new’ CCD’s, and showed two rebrightenings after the primary outburst had finished. One rebrightening was seen in each of the 2013 and 2015 outbursts.
The light curve shown here is of the 1995 outburst, and was compiled by me during my BAAVSS directorship from observations from observers around the world. The two post outburst events can be seen clearly.
So, if your following AL Com at the moment and you lose it either visually or with your CCD, continue to monitor for a couple of weeks longer. There is no guarantee it will brighten again but it just might…
Gary
The scopes are C14’s.
The value of unfiltered measurements is immense. See the number of papers in the BAAJ or other (professional) journals which contain unfiltered data from amateurs to see just how important they are.
Simple patrolling for outbursts for example – deeper images unfiltered or less exposure time. Time series observations during outburst are just as valuable unfiltered – it’s the period and amplitude which are important here, not necessarily the intrinsic brightness. And of course, an unfiltered observation is better than no observation at all!
Gary
I’ve picked it up a few times at minimum with the old BRT and new COAST telescopes, unfiltered and 60-80 seconds exposure varying between 18.5-19.5. It has quite a range at quiescence ~18.5-21.00. Seen a few outbursts visually too. More exciting than ogling the galaxy 😉
Gary
You might also try it’s alternate designation of IRAS 051853227.
There are a few pages where it’s listed in Kenyons classic book ‘Symbiotic Stars’. If you contact me off-list, I’ll copy the relevant pages for you – but the book is still available and it’s worth owning.
Good luck,
Gary
David,
If there is any fog to be burned off, it’s concentrating on Birmingham first but alas it just predicts. I too want to see ASASSN-19de (easier to write than the TCP designation).
Good luck
Gary
I remember seeing it in the late 1970’s visually with a 10inch F6.5 newtonian. It could have been 1978-79 but I’m having trouble locating that observation in my files (which is why I’m late to the discussion). I do recall that it was a very difficult observation to make, with the separation at or near maximum distance I think. If I find my notes, I’ll come back. Don’t think I dreamt it!
Gary
