- vsnet-outburst - ooruri.kusastro.kyoto-u.ac.jp

[vsnet-outburst 31602] HW Boo
by Gary Poyner 23 Dec '25

23 Dec '25

The UGSU star HW Boo is in bright outburst, possibly a superoutburst, the first one since March 2024... Dec 17.447 17.678V Dec 18.540 17.500V Dec 21.535 13.911V AAVSOnet DSO-35, Fort Davis, Texas. Gary -- ------------------------------------------------------ Gary Poyner FRAS garypoyner(a)gmail.com www.variablestars.co.uk

1 0

[vsnet-outburst 31601] ASASSN-22nd (=AT2025ahnc= ZTF25acibbkf =ASASSN-25fb); a new fast-decaying outburst
by Yusuke Tampo 19 Dec '25

19 Dec '25

ASASSN-22nd (=AT2025ahnc= ZTF25acibbkf =ASASSN-25fb); a new fast-decaying outburst GOTO, ZTF, and ASASSN have detected a new outburst from a known CV candidate ASASSN-22nd. https://vsx.aavso.org/index.php?view=detail.top&oid=2345330 https://www.wis-tns.org/object/2025ahnc https://lasair-ztf.lsst.ac.uk/objects/ZTF25acibbkf/ https://asas-sn.osu.edu/sky-patrol/coordinate/19517db9-fb36-4d9c-a94d-2ca87… This outburst shows a fast decay, approximately 1 mag/d. Considering its large amplitude(>7mag), relatively short outburst cycle (~3 years), and fast decay of the outburst, this outburst could be a precursor outburst of a dwarf nova superoutburst, or even from an AM CVn star. Although the system is currently faint (~18.5 mag in ATLAS), if the system returns to a bright state, time-resolved photometries will be encouraged. Best regards, Yusuke -- ---------------------------------------------- South African Astronomical Observatory, Postdoc fellow Yusuke TAMPO / 反保雄介 EMAIL: tampo(a)kusastro.kyoto-u.ac.jp ALT. EMAIL: yusuke(a)saao.ac.za ----------------------------------------------

1 0

[vsnet-outburst 31600] Outbursts 16,17/12/2025
by Rod Stubbings 17 Dec '25

17 Dec '25

Outbursts and selected activity. object YYMMDD(UT) mag code remarks CENMU 251216.671 134 Stu.RASNZ active CENV342 251216.624 154 Stu.RASNZ active CENV803 251216.680 136 Stu.RASNZ active CNCSY 251216.701 113 Stu.RASNZ outburst ERIBF 251216.494 138 Stu.RASNZ active ERIBF 251217.476 139 Stu.RASNZ active GEMUV 251216.620 150 Stu.RASNZ active HYAV392 251216.662 143 Stu.RASNZ active INDTT 251216.471 131 Stu.RASNZ active INDTT 251217.462 131 Stu.RASNZ active OCTAA 251216.599 148 Stu.RASNZ outburst ORIBI 251216.500 142 Stu.RASNZ active ORIBI 251217.542 141 Stu.RASNZ active ORICN 251216.501 137 Stu.RASNZ outburst ORICN 251217.543 134 Stu.RASNZ active ORICZ 251217.549 134 Stu.RASNZ outburst PICAR 251216.487 157 Stu.RASNZ outburst PICAR 251217.489 132 Stu.RASNZ active PUPBV 251216.522 136 Stu.RASNZ outburst PUPBV 251217.535 138 Stu.RASNZ active PUPBX 251217.534 150 Stu.RASNZ outburst PUPCL 251216.524 143 Stu.RASNZ active PUPCL 251217.535 148 Stu.RASNZ active PUPHO 251216.521 139 Stu.RASNZ outburst PUPHO 251217.553 140 Stu.RASNZ active PYXVZ 251216.574 132 Stu.RASNZ outburst PYXVZ 251217.560 151 Stu.RASNZ active TUCVW 251216.596 158 Stu.RASNZ outburst ASASSN-14FF 251216.492 148 Stu.RASNZ outburst ASASSN-14FF 251217.478 151 Stu.RASNZ active -- Rod Stubbings Tetoora Road Observatory Victoria, Australia Honorary Associate member Astronomical Society of Australia Telescope: "Infinity" 22" f/3.8 stubbo(a)dcsi.net.au http://rodstubbingsobservatory.wordpress.com/

1 0

[vsnet-outburst 31594] ASASSN-25eq: new WZ Sge-type dwarf nova, likely a period bouncer
by Yusuke Tampo 17 Dec '25

17 Dec '25

ASASSN-25eq: new WZ Sge-type dwarf nova, likely a period bouncer ASASSN discovered ASASSN-25eq on 2025-11-13.18 UT at 15.07 mag. Then it brightened to g=14.0 mag on 2025-11-15. The VSX lists g=21.9 mag as the counterpart, hence the outburst amplitude is ~8 mag. https://vsx.aavso.org/index.php?view=detail.top&oid=10868208 https://asas-sn.osu.edu/sky-patrol/coordinate/579ca10e-176d-4c3b-958f-03a39… Josch Hambsh and Berto Monard have reported the time-resolved observations of ASASSN-25eq. The light curve shows a 1-mag dip around 2025-11-25 UT. After this dip, clear superhumps are present, with a period of ~0.0645 d. There is no clear modulation before the dip. Thus, ASASSN-25eq is a new WZ Sge-type dwarf nova, with a double-superoutburst feature often observed in a period bouncer system. See e.g. https://ui.adsabs.harvard.edu/abs/2018PASJ...70...47K/abstract Given the absence of clear early superhumps, ASASSN-25eq is presumably a face-on system. A spectrum taken with the Mookodi/Lesedi telescope on 16 Nov. is dominated by Balmer absorption lines, which supports this interpretation. Time-resolved observations are encouraged. Best regards, Yusuke -- ---------------------------------------------- South African Astronomical Observatory, Postdoc fellow Yusuke TAMPO / 反保雄介 EMAIL: tampo(a)kusastro.kyoto-u.ac.jp ALT. EMAIL: yusuke(a)saao.ac.za ----------------------------------------------

1 1

[vsnet-outburst 31598] TCP J07454958-2442056: most likely a WZ Sge-type dwarf nova
by Yusuke Tampo 15 Dec '25

15 Dec '25

TCP J07454958-2442056: most likely a WZ Sge-type dwarf nova TCP J07454958-2442056 was discovered by Yuji Nakamura on 13th Oct 2025 at 14.0 mag (unfiltered). According to VSX, the outburst amplitude is ~8.2 mag. https://vsx.aavso.org/index.php?view=detail.top&oid=10868099 Josch Hambsch and Sjoerd Dufoer have reported the time-resolved observations of this source. The light curve shows possible superhumps with a period of ~0.055 d, although I cannot conclude due to its faintness and 1-d aliases. Given its large outburst amplitude, almost 40-d outburst duration, and short superhump period, TCP J07454958-2442056 is most likely a new WZ Sge-type dwarf nova. Note that the system has already faded below the detection level of ATLAS. https://fallingstar-data.com/forcedphot/queue/3502597/ Best regards, Yusuke -- ---------------------------------------------- South African Astronomical Observatory, Postdoc fellow Yusuke TAMPO / 反保雄介 EMAIL: tampo(a)kusastro.kyoto-u.ac.jp ALT. EMAIL: yusuke(a)saao.ac.za ----------------------------------------------

1 0

[vsnet-outburst 31597] Outbursts 10/12/2015
by Rod Stubbings 11 Dec '25

11 Dec '25

Outbursts and selected activity. object YYMMDD(UT) mag code remarks CAROQ 251210.546 142 Stu.RASNZ active CENMU 251210.640 123 Stu.RASNZ outburst CENNN 251210.630 140 Stu.RASNZ outburst CENV803 251210.672 136 Stu.RASNZ outburst CHAST 251210.543 138 Stu.RASNZ outburst CMADM 251210.522 148 Stu.RASNZ active CMAHL 251210.521 119 Stu.RASNZ active CMISV 251210.676 132 Stu.RASNZ active CNCGZ 251210.658 132 Stu.RASNZ outburst ERIBF 251210.484 131 Stu.RASNZ active ERILT 251210.483 156 Stu.RASNZ active ERIPS 251210.661 127 Stu.RASNZ outburst GEMUV 251210.687 147 Stu.RASNZ outburst HYAV392 251210.642 148 Stu.RASNZ outburst HYIVW 251210.498 96 Stu.RASNZ active INDTT 251210.474 129 Stu.RASNZ active ORICN 251210.516 138 Stu.RASNZ active ORIV1159 251210.514 145 Stu.RASNZ active PAVV548 251210.478 148 Stu.RASNZ active PEGHX 251210.463 133 Stu.RASNZ active PEGIP 251210.461 125 Stu.RASNZ active PUPUY 251210.593 138 Stu.RASNZ active PUPCL 251210.591 155 Stu.RASNZ outburst PUPHO 251210.623 143 Stu.RASNZ active ASASSN-14GR 251210.488 151 Stu.RASNZ active ASASSN-14HQ 251210.506 157 Stu.RASNZ active NSV 35 251210.531 150 Stu.RASNZ active DDE 77 251210.492 136 Stu.RASNZ outburst -- Rod Stubbings Tetoora Road Observatory Victoria, Australia Honorary Associate member Astronomical Society of Australia Telescope: "Infinity" 22" f/3.8 stubbo(a)dcsi.net.au http://rodstubbingsobservatory.wordpress.com/

1 0

[vsnet-outburst 31596] Outbursts 9/12/2025
by Rod Stubbings 10 Dec '25

10 Dec '25

Outbursts and selected activity. object YYMMDD(UT) mag code remarks CAROQ 251209.521 141 Stu.RASNZ outburst CMADM 251209.491 144 Stu.RASNZ outburst CMAHL 251209.490 119 Stu.RASNZ active CMISV 251209.542 132 Stu.RASNZ outburst ERIBF 251209.486 134 Stu.RASNZ outburst ERILT 251209.454 156 Stu.RASNZ outburst HYIVW 251209.457 94 Stu.RASNZ active INDTT 251209.452 126 Stu.RASNZ outburst ORICN 251209.506 131 Stu.RASNZ active ORIV1159 251209.490 140 Stu.RASNZ outburst PAVGS 251209.478 150 Stu.RASNZ outburst PAVV548 251209.480 143 Stu.RASNZ outburst PUPUY 251209.494 137 Stu.RASNZ outburst PUPBX 251209.492 154 Stu.RASNZ outburst PUPHO 251209.497 143 Stu.RASNZ active ASASSN-14GR 251209.448 150 Stu.RASNZ outburst ASASSN-14HQ 251209.515 149 Stu.RASNZ outburst NSV 35 251209.510 150 Stu.RASNZ outburst -- Rod Stubbings Tetoora Road Observatory Victoria, Australia Honorary Associate member Astronomical Society of Australia Telescope: "Infinity" 22" f/3.8 stubbo(a)dcsi.net.au http://rodstubbingsobservatory.wordpress.com/

1 0

[vsnet-outburst 31595] ASASSN-25en: new SU UMa-type dwarf nova
by Yusuke Tampo 02 Dec '25

02 Dec '25

ASASSN-25en: new SU UMa-type dwarf nova ASASSN discovered ASASSN-25en on 2025-11-03 UT at 14.94 mag. The outburst amplitude in the VSX is ~7.5 mag. https://vsx.aavso.org/index.php?view=detail.top&oid=10868163 Josch Hambsch and Itoh-san have reported the time-resolved observations. The light curve after 2025-11-11 UT shows a single-peaked superhump with a period of either 0.06003(3) or 0.06390(3) d. Thus, ASASSN-25en is a new SU UMa-type dwarf nova. The rapid decline from the outburst was observed around 2025-11-21 UT. Best regards, Yusuke -- ---------------------------------------------- South African Astronomical Observatory, Postdoc fellow Yusuke TAMPO / 反保雄介 EMAIL: tampo(a)kusastro.kyoto-u.ac.jp ALT. EMAIL: yusuke(a)saao.ac.za ----------------------------------------------

1 0

[vsnet-outburst 31593] Outbursts 26/11/2025
by Rod Stubbings 27 Nov '25

27 Nov '25

Outbursts and selected activity. object YYMMDD(UT) mag code remarks APSV394 251126.483 144 Stu.RASNZ outburst CAROQ 251126.494 141 Stu.RASNZ active CHAZ 251126.451 128 Stu.RASNZ active CHAST 251126.454 142 Stu.RASNZ outburst CMADM 251126.573 150 Stu.RASNZ active CMAHL 251126.572 119 Stu.RASNZ active DORBC 251126.446 149 Stu.RASNZ active ERIXZ 251126.499 151 Stu.RASNZ active ERIAH 251126.497 138 Stu.RASNZ active HYIVW 251126.444 126 Stu.RASNZ outburst HYIVW 251126.492 123 Stu.RASNZ HYIVW 251126.569 120 Stu.RASNZ INDTU 251126.474 140 Stu.RASNZ active INDCS 251126.480 118 Stu.RASNZ active OCTDT 251126.481 146 Stu.RASNZ active PUPBV 251126.570 138 Stu.RASNZ active PUPBX 251126.569 153 Stu.RASNZ active PUPHO 251126.576 144 Stu.RASNZ active SGRV730 251126.440 142 Stu.RASNZ outburst TUCVW 251126.487 156 Stu.RASNZ outburst VOLSY 251126.493 150 Stu.RASNZ active NSV 35 251126.485 150 Stu.RASNZ outburst DDE 76 251126.467 150 Stu.RASNZ active SSS 100511:061754-362655 251126.461 149 Stu.RASNZ active -- Rod Stubbings Tetoora Road Observatory Victoria, Australia Honorary Associate member Astronomical Society of Australia Telescope: "Infinity" 22" f/3.8 stubbo(a)dcsi.net.au http://rodstubbingsobservatory.wordpress.com/

1 0

[vsnet-outburst 31592] TCP J06364062+3318310: new SU UMa-type dwarf nova
by tonny.vanmunster＠gmail.com 26 Nov '25

26 Nov '25

Dear colleagues, TCP J06364062+3318310 was discovered by K. Sokolovsky et al. (NMW Survey) on 2025 Nov 17.99 at mag 13.6CV. The quiescent counterpart is a 21.3 r mag star, implying an outburst amplitude of ~8 mag. I have just completed the analysis of my unfiltered CCD time-series observations of TCP J06364062+3318310, obtained on 2025 Nov 25/26 at CBA Extremadura Observatory. The data were acquired under clear skies with a 0.40-m f/5.1 telescope and a Moravian G2-4000 CCD camera. I also obtained observations on several nights prior to Nov 25/26, but those did not reveal any obvious modulation. In contrast, the Nov 25/26 light curve clearly shows regular superhump modulations with an amplitude of 0.30 mag. A period analysis using ANOVA, Lomb-Scargle, Generalized-Lomb-Scargle and PDM methods (Peranso 3.1) yields a combined superhump period of 0.0661 +/- 0.0008d. The object was measured at mag CV = 15.3 on Nov 26th. Image calibration and photometry were carried out using the latest release of Phoranso, which enabled simultaneous photometry of several additional variable stars in the same field of view. These results establish TCP J06364062+3318310 as a new SU UMa-type dwarf nova. Further follow-up observations are strongly encouraged to refine the superhump period and study its evolution. I will submit my observations to AAVSO, CBA and VSNET for further analysis. With kind regards, Tonny --- Tonny Vanmunster CBA Belgium Observatory CBA Extremadura Observatory http://www.cbabelgium.co <http://www.cbabelgium.com/> m PERANSO : The Light Curve and Period Analysis Software http://www.peranso.co <http://www.peranso.com/> m PHORANSO: Photometric Reduction and Analysis Software http://www.phoranso.com <http://www.phoranso.com/>

1 0