(cba:news) August stars, redux... plus CI Aql and the nova project

[Joe Patterson]

Oops, the eyes are not what they used to be!... and they were never that 
good anyway.  As Damien suspects, the proper names are FO Aqr and V1223 
Sgr. Good to know someone has high standards (evident in his photometry 
too).

Also, I omitted one critical star, which I would rate as the highest 
priority for August-September observing: the recurrent nova CI Aql.  I 
stopped thinking about this star years ago, after learning that its 
orbital period is long (~16 hours).  But others, wiser than I, 
recognized that as far as recurrent novae are concerned, it's definitely 
in the "short Porb" class.  Eclipsing too, and on the celestial equator. 
Those should award very high CBA points.  So it really should be one of 
our faves, and now is the season.  I'm really eager to see CBA data on it.

While long observations are very desirable for this 16-hour star, don't 
get too frisky with airmass (i.e., you probably should observe the 2.0 
airmass limit).

We'll be getting some interesting papers out on "old novae" this year, 
and it would be good to start thinking about light curves of "old novae" 
(long past outburst).  Now that ASAS-SN, ZTF, etc. are revealing so many 
dwarf novae, the novae are getting somewhat neglected.  Since each nova 
takes years to play out its particular messages, while each dwarf nova 
is a matter of days-to-weeks, that's understandable.  But in my opinion, 
the incremental knowledge we get from novae is now much higher (per 
observing hour, say)  As the seasons march on, I'll discuss priorities 
re nova targets.

Koji Mukai has a very famous online bible for intermediate polars, and 
recently updated one on recent novae too:

https://asd.gsfc.nasa.gov/Koji.Mukai/novae/novae.html

Only a few of these stars will ever graduate to become CBA targets - 
they're typically quite faint, in Sco-Sgr, highly reddened, etc.  But 
for those special interest in novae, this belongs as one of the revered 
texts.

joe



-------- Forwarded Message --------
Subject: Re: (cba:news) august stars
Date: Fri, 31 Jul 2020 15:36:19 -0400
From: Damien Lemay <damien.lemay at globetrotter.net>
To: Joe Patterson <jop at astro.columbia.edu>

Hi Joe,

Two questions:

1- Could it be FO Aqr instead of FQ Aqr (type PVTELI)?

2- V1223 --- from which constellation?

Damien


On 2020-07-30 9:01 a.m., Joe Patterson wrote:

> 2. Intermediate polars (DQ Her stars).  Right up our alley to measure 
> period change, since we have baselines of 5-20 years.  The ones needing 
> just occasional observation are FQ Aqr and AO Psc. 

V1223 is more
> interesting since it has been much more active this year, and a 
> still-unsettled question is the connection between brightness and period 
> change.  It will take some patience to settle this.
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