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AAVSO Alert Notice 705: Rare outburst of the WZ Sge star PQ Andromedae (Nova And 1988)

29 May 2020

AAVSO Forum threads (scroll to the bottom of a thread for latest posts):
- Cataclysmic Variables:
- Time Sensitive Alerts:

Observers are encouraged to participate in the AAVSO forums listed above for this event, and to visit the AAVSO CV Section webpage. Also, observers can find AAVSO-related information on current CV activity at

Event: Rare outburst of the WZ Sagittae-type dwarf nova PQ Andromedae ("Nova" Andromedae 1988)

Discovered by: Kenji Hirosawa (Aichi, Japan)

Discovery magnitude: 10.48 cG (using 20cmL (FL 1000mm) + CANON X9)
Discovery date: 2020 May 28.77633 UT

Coordinates (2000.0): R.A. 02 29 29.57   Decl. +40 02 39.8  (from VSX page)

Discussion: PQ And was discovered as Nova And 1988 on March 21 by David McAdam (Telford, UK; IAUC 4570). It was presumed to be a nova (IAUC 4620) but as the spectrum was lost after initial review it was not available for additional study.

PQ And is now known to be a WZ Sge-type system (UGWZ+ZZ/GWLIB) and may be a period bouncer (Patterson et al. 2005, Publ. Astron. Soc. Pac., 117, 922). Previous outbursts were found by G. A. Richter on archival photographic plates taken in 1938 and 1967 (1990, IBVS No. 3546).

Observing recommendations: Time series are requested; the orbital period is 0.0560 d (80.6 min) so the cadence should be determined accordingly. Filtered photometry is preferred. PQ And is presently a morning target and difficult to observe, but observations made now are very important to capture superhump development.

Spectroscopy is also requested.

Observations reported to the AAVSO:
2020 Mar. 16.84030, <14.0 (E. Muyllaert, Oostende, Belgium);
19.81460, <14.5 (C. Allen, Farjestaden, Sweden);
22.85830, <14.5 (Allen);
Apr. 25.83472, <11.9 (P. Schmeer, Saarbrücken-Bischmisheim, Germany);
May. 28.77633, 10.48 cG (K. Hirosawa, Aichi, Japan; discovery (via [vsnet-alert 24302], see Note a);
29.07990, 10.3 (Muyllaert; confirmation);
29.088, 10.5 (G. Poyner, Birmingham, UK);
29.09375, 10.7 (Schmeer);

Charts: Charts with comparison stars for PQ And may be created using the AAVSO Variable Star  Plotter (VSP). Please be sure to check VSP to make certain you have the latest version.

Submit optical observations: Please submit photometry and visual observations to the AAVSO International Database using the name PQ AND.

Submit spectroscopic observations: Please submit spectroscopy reports to the AAVSO Spectroscopy Database (AVSpec).

a. Hirosawa's original discovery announcement stated the date incorrectly as 20200528.27633 in [vsnet-alert 24301].

Congratulations to Kenji Hirosawa on his discovery of this rare outburst!

This Alert Notice was compiled by Elizabeth O. Waagen.

PGIR20dkk: possible nova in Sagittarius

V1363 Cyg in outburst! (brightening since April 26)

PNV J17120009-4017560: possible nova (12.7 mag) in Scorpius
(spectroscopy and multiband photometry are *still* required!)

AAVSO Alert Notice 703: 

TCP J21040470+4631129 spectroscopy and photometry urgently requested

1 April 2020

AAVSO Forum threads (scroll to the bottom of a thread for latest posts):

- Campaigns and Observation Reports:

- Cataclysmic Variables:

- Spectroscopy:

Dr. Juan Echevarria (Instituto de Astronomia, UNAM) has requested AAVSO observers' assistance in carrying out spectroscopy and photometry of the WZ Sagittae-type cataclysmic variable TCP J21040470+4631129, which is undergoing a superoutburst.

Dr. Echevarria asks spectroscopists "for direct images with a narrow filter at  and nearby continuum."

Photometry in V (multiple observations per night) is also requested, as most large ground-based telescopes are closed at present. TCP J21040470+4631129 is a morning object, but knowing the magnitude is crucial so photometry is essential.

Please continue spectroscopy and photometry of TCP J21040470+4631129 at least through the end of April 2020.

This Alert Notice is complementary to the request for photometry by Dr. Boris Gänsicke in AAVSO Alert Notice 702. Observers are reminded that knowing the V magnitude of TCP J21040470+4631129 is essential to that campaign. Dr. Echevarria asked that this message from Dr. Gänsicke be included here:

"HST/COS far-ultraviolet spectroscopy of [TCP J21040470+4631129] are scheduled for 10 April 2020 17:15:48 – 23:05:48 UT. The COS far-ultraviolet detector has a limited dynamical range, and over-illumination risks permanent damage. Therefore, the standard procedure to observe highly variable sources is to have daily monitoring in place to ensure that the target remains quiescent in the 24h prior to the HST observations. Given that TCP has just entered an outburst, it is now mission-critical to closely monitor the flux level over the next ten days, so that STScI can gauge whether it is safe to observe TCP. Given the way HST operates, the schedule cannot be altered at this point, and should TCP remain too bright, or the monitoring be insufficiently dense, HST will observe a blank piece of sky instead, resulting in the loss of four space-craft orbits.”

TCP J21040470+4631129 has a range in V of 8.4–18.1. The most recent observations submitted to the AAVSO International Database include:

2020 Mar. 28.18190 UT, 15.170 V +/-0.024 (S. Dufoer, Brussels, Belgium);

28.18318, 15.173 V +/-0.084 (Dufoer);

30.15139, 15.4 CV (K. Wenzel, Grossostheim, Germany);

30.16976, 15.144 V +/-0.017 (F. Dubois, Zillebeke, Belgium);

30.17125, 15.491 B +/-0.019 (Dubois);

30.17275, 14.758 R +/-0.022 (Dubois);

30.17426, 14.346 I +/-0.046 (Dubois);

31.47796, 11.115 CV +/-0.004 (D. Denisenko, Moscow, Russian Fed.);

Apr. 01.01507, 10.638 B +/-0.020 (D. Boyd, Wantage, Oxon, UK);

01.01558, 10.774 I +/-0.022 (Boyd);

01.01598, 10.799 R +/-0.027 (Boyd);

01.01627, 10.826 V +/-0.018 (Boyd);

01.054, 10.6 TG (R. Fidrich, Budapest, Hungary);

Coordinates (J2000):  R.A. 21 04 04.68   Dec. +46 31 14.5

Charts with comparison stars for TCP J21040470+4631129 may be created using the AAVSO Variable Star Plotter (VSP).

Please submit spectroscopy reports to Dr. Echevarria at <> and to the AAVSO Spectroscopy Database (AVSpec).

Please submit all photometry observations to the AAVSO International Database using the name TCP J21040470+4631129.

This Alert Notice was compiled by Elizabeth O. Waagen.

AAVSO Alert Notice 702: 

TCP J21040470+4631129 to be observed with HST

27 March 2020

AAVSO Forum threads (scroll to the bottom of a thread for latest posts):

- Campaigns and Observation Reports:

- Cataclysmic Variables:

Dr. Boris Gaensicke (University of Warwick) has requested AAVSO assistance in monitoring the WZ Sge-type dwarf nova TCP J21040470+4631129 (Cygnus) in support of observations scheduled with the Hubble Space Telecope for 2020 April 10, 17:30:39 – 23:05:48 UT.

AAVSO observations are essential to know the state of TCP J21040470+4631129 in order to ensure that the system is NOT in outburst when observed with HST. AAVSO observations made 24 hours before the HST observing time will be used to make a go/no-go decision; AAVSO data will be used in the analysis of the resulting HST data.

Nightly snapshots in V are requested beginning now and continuing through April 13. Intensive monitoring is requested April 7-10. During the period of intensive observations, prompt submission of observations will be essential. The most critical need for a positive observation is the night of April 9/10 (as early on the morning of April 10 as possible). Visual observations are also welcome.

TCP J21040470+4631129 has a range in V of 8.4-18.1. Its last major outburst occurred in July 2019, when it reached magnitude 8.293 V, and was followed by several re-brightenings, the most recent of which occurred in December 2019. The most recent observation of TCP J21040470+4631129 in the AAVSO International Database shows it at magnitude 15.3 CV on 2020 Feb. 22.20486 UT (K. Wenzel, Grossostheim, Germany).

Coordinates (J2000): R.A. 21 04 04.68  Dec. +46 31 14.5

Charts with a comparison stars for TCP J21040470+4631129 may be created using the AAVSO Variable Star Plotter (VSP).

Please report all observations to the AAVSO International Database using the name TCP J21040470+4631129.

This Alert Notice was compiled by Elizabeth O. Waagen.

The Z CamPaign

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.

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.


Last updated 06:35 UT on 4 June 2020

New outbursts and unusual activity reported in the last 72 hours


HO Del (UGSU, normal outburst)

QW Ser
SDSS J100515.39+191108.0

Current superoutbursts (since ...)
PQ And :# (20200528; UGWZ:, first recorded outburst since discovery in 1988)
RZ LMi (20200513; UGSU, ER UMa subtype, precursor outburst 20200510–11)
GP CVn (20200511, UGSU)
CS Ind (20200511, UGSU)
MS Lyn (20200511, UGSU)
RX Vol (20200511, UGSU)
IR Gem (20200509, UGSU)
Gaia20cfj (20200509)
SDSS J124058.03-015919.2 # (20200429; AM CVn star, 4 rebrightenings, Psh= 0.02598(5) d) 

Z Cam-type dwarf novae at standstill
HL CMa (since 20191106 or earlier)
Z Cam (since 20181012)
V2837 Ori (20191106–20191123; IW And star, eclipsing, Porb= 0.2761069 d)
CK Eri (20190925–20191029, outburst 20191030; IW And star?)
RX And (20190614–20190714)
V507 Cyg (20190403–20190706, IW And star)
AT Cnc (20190212 – 20190603)
1RXS J062954.6-033520 (20190228–20190316)
UY Pup (20181129–20181217)

# indicates a noteworthy or unusual outburst
:  indicates confirmation required
'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.


03 June 2020

For new papers on CV's see astro-ph

M. D. Stritzinger (Aarhus), F. Taddia (Aarhus), M. Fraser (Dublin), T. M. Tauris (Aarhus), C. Contreras, S Drybye, L. Galbany, S. Holmbo, N. Morrell, A. Pastorello, M. M. Phillips, G. Pignata, L. Tartaglia, N.B. Suntzeff, J. Anais, C. Ashall, E. Baron, C. R. Burns, P. Hoeflich, E. Y. Hsiao, E. Karamehmetoglu, T. J. Moriya, G. Bock, A. Campillay, S. Castellon, C. Inserra, C. Gonzalez, P. Marples, S. Parker, D. Reichart, S. Torres-Robledo, D. R. Young

O. Segura Montero, S.H. Ramirez, J. Echevarria

Susanne M Hoffmann, Nikolaus Vogt, Philipp Protte

Taichi Kato, Yasuyuki Wakamatsu, Naoto Kojiguchi, Mariko Kimura, Ryuhei Ohnishi, Keisuke Isogai, Keito Niijima, Tomohiro Yoshitake (Kyoto U), Yuki Sugiura, Sho Sumiya, Daiki Ito, Kengo Nikai, Hanami Matsumoto, Katsura Matsumoto, Tonny Vanmunster, Franz-Josef Hambsch, Hiroshi Itoh, Julia V. Babina, Oksana I. Antonyuk, Alex V. Baklanov, Elena P. Pavlenko, Berto Monard, Shawn Dvorak

Susanne M. Hoffmann

E.Pavlenko, K. Niijima, P. Mason, N.Wells, A. Sosnovskij, K. Antonyuk, A. Simon, N. Pit, C. Littlefield, H. Itoh, S. Kiyota, T.Tordai, P. Dubovsky, T.Vanmunster, G. Stone, T. Kato, A. Sergeev, V. Godunova, E. Lyumanov, O. Antonyuk, A. Baklanov, Ju. Babina, K. Isogai, Ya. Romanyuk, V.Troianskyi, V. Kashuba

J. Casares, T. Muñoz-Darias, D. Mata Sanchez, P.A. Charles, M.A.P. Torres, M. Armas Padilla, R.P. Fender, J. Garcia-Rojas

G. J. M. Luna (1,2), T. Nelson (3), K. Mukai (4,5), J. L. Sokoloski (6,7) ((1) CONICET-Universidad de Buenos Aires, Instituto de Astronomía y Física del Espacio (IAFE), (2) Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Buenos Aires, Argentina, (3) Department of Physics and Astronomy, University of Pittsburgh, (4) CRESST and X-ray Astrophysics Laboratory, NASA Goddard Space Flight Center, (5) Department of Physics, University of Maryland, Baltimore County, (6) Columbia Astrophysics Lab, Columbia University, (7) Large Synoptic Survey Telescope Corporation)

Bradley E. Schaefer, David Boyd, Geoffrey C. Clayton, Juhan Frank, Christopher Johnson, Jonathan Kemp, Ashley Pagnotta, Joseph O. Patterson, Miguel Rodriguez Marco, Limin Xiao

Taichi Kato (Kyoto U), Elena P. Pavlenko, Nikolaj V. Pit, Kirill A. Antonyuk, Oksana I. Antonyuk, Julia V. Babina, Aleksei V. Baklanov, Aleksei A. Sosnovskij, Sergey P. Belan, Yutaka Maeda, Yuki Sugiura, Sho Sumiya, Hanami Matsumoto, Daiki Ito, Kengo Nikai, Naoto Kojiguchi, Katsura Matsumoto, Pavol A. Dubovsky, Igor Kudzej, Tomas Medulka, Yasuyuki Wakamatsu, Ryuhei Ohnishi, Takaaki Seki, Keisuke Isogai, Andrii O. Simon, Yaroslav O. Romanjuk, Alexsandr R. Baransky, Aleksandr V. Sergeev, Vira G. Godunova, Inna O. Izviekova, Volodymyr A. Kozlov, Aleksandr S. Sklyanov, Roman Ya. Zhuchkov, Alexei G. Gutaev, Vasyl O. Ponomarenko, Volodymyr V. Vasylenko, Ian Miller, Kiyoshi Kasai, Shawn Dvorak, Kenneth Menzies, Enrique de Miguel, Stephen M. Brincat, Roger D. Pickard

Keisuke Isogai, Taichi Kato, Akira Imada, Tomohito Ohshima, Naoto Kojiguchi, Ryuhei Ohnishi, Franz-Josef Hambsch, Berto Monard, Seiichiro Kiyota, Hideo Nishimura, Daisaku Nogami

G. Ramsay, M. J. Green, T. R. Marsh, T. Kupfer, E. Breedt, V. Korol, P.J. Groot, C. Knigge, G. Nelemans, D. Steeghs, P. Woudt, A. Aungwerojwit

Luis Alberto Canizares, Peter Garnavich, Colin Littlefield, Joshua Pepper, Allyson Bieryla, Supachai Awiphan, Siramas Komonjinda

Anna F. Pala, Linda Schmidtobreick, Claus Tappert, Boris T. Gänsicke, Andrea Mehner

G. J. M. Luna, K. Mukai, J. L. Sokoloski, T. Nelson, P. Kuin, A. Segreto, G. Cusumano, M. Jaque Arancibia, N. E. Nunez

Mariko Kimura et al

M. J. Darnley, S. Starrfield

Mariko Kimura, Keisuke Isogai, Taichi Kato, Kenta Taguchi, Yasuyuki Wakamatsu, Franz-Josef Hambsch, Berto Monard, Gordon Myers, Shawn Dvorak, Peter Starr, Stephen M. Brincat, Enrique de Miguel, Joseph Ulowetz, Hiroshi Itoh, Geoff Stone, Daisaku Nogami

Joseph Patterson et al.

Paula Szkody, Mark E. Everett, Zhibin Dai, Donald Serna-Grey

John R. Thorstensen, Frederick A. Ringwald, Cynthia J. Taylor, Holly A. Sheets, Christopher S. Peters, Julie N. Skinner, Erek H. Alper, Kathryn E. Weil

Mariko Kato (Keio Univ.), Izumi Hachisu (Univ. of Tokyo), Hideyuki Saio (Tohoku Univ.)

E. Aydi, K. L. Page, N. P. M. Kuin, M. J. Darnley, F. M. Walter, P. Mróz, D. Buckley, S. Mohamed, P. Whitelock, P. Woudt, S. C. Williams, M. Orio, R. E. Williams, A. P. Beardmore, J. P. Osborne, A. Kniazev, V. A. R. M. Ribeiro, A. Udalski, J. Strader, L. Chomiuk

Michael M. Shara, Trisha F. Doyle, Ashley Pagnotta, James T. Garland, Tod R. Lauer, David Zurek, Edward A. Baltz, Ariel Goerl, Attay Kovetz, Tamara Machac, Juan Madrid, Joanna Mikolajewska, J. D. Neill, Dina Prialnik, Doug L. Welch, Ofer Yaron

J.M Hameury & J.P Lasota

V. V. Lukin, K. L. Malanchev, N. I. Shakura, K. A. Postnov, V. M. Chechetkin, V. P. Utrobin

Authors: A. F. Pala, B. T. Gänsicke, D. Townsley, D. Boyd, M. J. Cook, D. De Martino, P. Godon, J. B. Haislip, A. A. Henden, I. Hubeny, K. M. Ivarsen, S. Kafka, C. Knigge, A. P. LaCluyze, K. S. Long, T. R. Marsh, B. Monard, J. P. Moore, G. Myers, P. Nelson, D. Nogami, R. Pickard, G. Poyner, D. E. Reichart, D. Rodriguez Perez, M. R. Schreiber, J. Shears, E. M. Sion, R. Stubbings, P. Szkody, M. Zorotovic

Liam K Hardy, Martin J McAllister, Vik S Dhillon, Stuart P Littlefair, Madelon C P Bours, Elme Breedt, Tim Butterley, Anurak Chakpor, Puji Irawati, Paul Kerry, Tom R Marsh, Steven G Parsons, Chris D J Savoury, Richard W Wilson, Patrick A Woudt