(cba:news) July-August 2019 stars (Joe Patterson) [2019-07-05T20:58:02Z]

Hi CBAers,

Here's an accounting of July-August stars, sorted by "program type".

DQ HER STARS (intermediate polars). Many are in the sky now, and the 
world has issued us the task of keeping track of them.  That means 
nightly 2-4 hour time series.  In most cases the periods are already 
decently known; next up is to measure the period *changes* (and for 
those of you new to the CBA, that's been our job for years).  In many 
cases, just *occasional* coverage is needed; no need to crazy on one 
star, unless you fine one you love - in which case, *definitely* go 
crazy on it!

The stars in question are AO Psc, V1223 Sgr, V4743 Sgr, NY Lup, V2069 
Cyg, V2306 Cyg.  Leave DQ Her itself to Lew Cook; he's the master of 
that star.

SUPERSOFT BINARIES.  v617 Sgr, for sure.  Maybe V Sge (excellent starter 
star, if you're altogether new to the CBA).  Maybe IM Nor.

RECENT NOVAE.  v1494 Aql, V1974 Cyg, V4743 Sgr, NR TrA (faint).  Maybe 
V1500 Cyg.  Unlike the advice given for the DQ Her stars, these stars 
are generally best served by saturation coverage.  Go "as long as you 
can, as often as you can".  The DQs are different because their spin 
periods are *short* - they communicate a lot of information in just a 
few hours.

MAXIE.  The and only.  MAXI J1820+070.  The scattered reports now say 
V~18.6.  Worth keeping an eye on.  The star is full of surprises.

That's the menu.  Lotta stars getting into good shape for publication. 
Maxie, very soon.  AM CVn, soon.  HP Lib, maybe a hundred more hours of 
close study.

joe


AM CVN STARS.  Just to finish up HP Lib.  Can't recommend any others at 
this time.  Most are very faint (19 or fainter).  But I'll spend a few 
days stodying the roster.

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