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Rob_K
26-01-2016, 11:27 AM
Recurrent nova LMC V1341 has erupted but is fading fast. The OGLE sky survey first announced the eruption in ATel #8578:
http://www.astronomerstelegram.org/?read=8578

Follow-up ATels #8586 & #8587 include spectroscopy and other details:
http://www.astronomerstelegram.org/?read=8586
http://www.astronomerstelegram.org/?read=8587

It's a very interesting object. I'm in my seventh year of observing it, just waiting for that little star to appear so it was pretty exciting when OGLE's announcement came even if I missed it (near Full Moon dammit). I thought there had only been two previous eruptions (1968 & 1990) but it turns out there have been two others, one recovered from ASAS archival data (2002) and one that was well-recorded in OGLE data (2010). Neither of these was observed at the time. The nova is very fast and can be missed easily. The 2010 eruption was certainly in a gap in my observations, Full Moon again!

The Swift team (ATel #8587) say:
"This eruption is the fifth recorded following 1968, 1990, 2002 and 2010, suggestive of a recurrence period of ~6 years. If confirmed, this system has the third shortest recurrence time after M31N 2008-12a (6 or 12 months) and M31N 1963-09c (5 year period), and is the closest of these short recurrence interval novae.... We also encourage searches of archival observations to find any missed eruptions focusing particularly on a recurrence period of approximately 6 years."

Lessons learnt:
* Forget the 20+ years, next eruption could be sooner than you think!
* Keep a high cadence of observing - weekly isn't good enough, at least with my gear.
* Ignore Moon phases, if I can get it under Full Moon as it's fading then bright outburst is no problem at all (not a pretty pic competition LOL).

Anyway, ugly pic attached, click to full size if necessary. :P

Cheers -

Tropo-Bob
26-01-2016, 01:45 PM
Good work on your persistence over many years, and now that something has happened, thanks for sharing with us all. I did not even know that this was a recurring Nova (maybe I have depended too much on Burnham's Handbooks for such information.)

I followed T Pyxis for many years and I was a thrilled to independently discover it had brightened some years ago. The fact that many tens (or maybe even hundreds) of amateurs discovered this before me did not lessen the thrill.

Rob_K
26-01-2016, 02:07 PM
Thanks Bob - the thrill of the hunt gets me and I image lots of fields looking for new novae and recurrent novae eruptions. I get really excited when discoveries are announced, so much so that I suspect that the old ticker mightn't handle it if I actually fluked discovering something myself! :astron: :scared2:

That must have been fantastic observing T Pyx without knowledge of what others had done before! :thumbsup:

Cheers -

Andrew Pearce
26-01-2016, 02:22 PM
Hi Rob

I remember getting only two observations of it back in 1990 before it faded. It's certainly an elusive bugger! Great to see it again and your image is almost exactly as it appeared visually.

I wonder if this is a recurrent nova or a WZ Sge type star with such frequent outbursts. I've never really understood what separates the two classes.

Cheers
Andrew

Rob_K
26-01-2016, 02:57 PM
Thanks Andrew. It would be magic to see it visually but by the time I got the alert the nova was already below the limiting magnitude of my little scope, even in a dark sky. I image the nova fields because you always hope that you catch these objects on the rise before they become visual objects, and my imaging is pretty basic with a DSLR & lens so easy & quick to do. The earlier the alert, the more valuable I suppose. But it's always fantastic to get a 'new star' in the eyepiece! :thumbsup:

As far as its type, the professionals have taken spectra over several eruptions now and are quite satisfied with the nova classification, so that'll do me! :lol:

Cheers -