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New Z Cam star discovered 

According to Gaia data, Gaia16akr appears to be a Z Cam star. The light curve indicates a standstill occurred between MJD 2454100 and 2454400.


Vital statistics from VSX:

J2000.0
19 25 54.82 -46 19 03.5 (291.47842 -46.31764)

Variability type
UGZ:

Mag. range
15.5 - 19.0 CV

AAVSO UID
000-BLX-412 

Constellation
Telescopium




T CrB currently bright

Is a nova eruption imminent?

1700 day AAVSO light curve

Although some observers are getting excited about the recent bright state of T CrB, this is actually well explained in Munari et al. 2016, New Astronomy 47, 7.

So, is T CrB ready to erupt again soon? Probably not, according to Munari et al. 

The last paragraph of the paper says, "There is an intriguing parallelism between SACT-2015 and what Hachenberg & Wellmann (1939) observed in 1938. The super-active state they caught occurred ∼70 years past the 1866 nova outburst, and SACT-2015 is occurring ∼70 years past the 1946 nova outburst. Is therefore everything in place for a new nova outburst in 2026, again ∼80 years past the last eruption?"

We may be getting closer to the next big event, and due to the unpredictable nature of recurrent novae T CrB certainly deserves vigilant monitoring in the coming years.



It’s all about the  standstills, those episodes where the star gets stuck at a mid-point between maximum and minimum. If it doesn’t exhibit standstills it isn’t a Z Cam star.






AM Her stars in need of further investigation








Data from Catalina Real Time Survey 
Drake et al. 2009, ApJ, 696, 87

Northern CVs brighter than 17th magnitude here.

Southern CV's brighter than 17th magnitude here.



ACTIVITY AT A GLANCE

New outbursts and unusual activity reported in the last 72 hours

Last updated 13:25 UT May 03, 2016

YYYYMMDD

20160503
EX Dra
V416 Dra

20160502
GY Hya
X Leo
NSV 4838

20160501
BP CrA
BR Lup



# indicates a noteworthy or unusual outburst
 
'Activity At A Glance' is gleaned from observations reported to AAVSO MyNewsFlash, BAAVSS-Alert, CVnet-Outburst, VSObs-share and VSNET-outburst. We sincerely thank all the observers who contribute timely observations and reports of activity to these email lists.

RECENT PAPERS ON CVs


For new papers on CV's see arxiv.org astro-ph



Authors: C.A. Hill, C.A. Watson, D. Steeghs, V.S. Dhillon, T. Shahbaz


Authors: Ashley Pagnotta, David Zurek


Authors: E. Mason, S.B. Howell


Authors: Joseph Patterson (1), Arto Oksanen (2), Jonathan Kemp (3), Berto Monard (2), Robert Rea (2), Franz-Josef Hambsch (2), Jennie McCormick (2), Peter Nelson (2), William Allen (2), Thomas Krajci (2), Simon Lowther (2), Shawn Dvorak (2), Jordan Borgman (1), Thomas Richards (2), Gordon Myers (2), Caisey Harlingten (4), Greg Bolt (2) ((1) Columbia Univ., (2) Center for Backyard Astrophysics, (3) Middlebury Coll., (4) Harlingten Obs.)