July 2026 - vsnet-outburst - ooruri.kusastro.kyoto-u.ac.jp

[vsnet-outburst 31695] TCP J02191736+2857158: growing superhump
by Hiromasa Hoke 25 Jul '26

25 Jul '26

TCP J02191736+2857158: growing superhump Moriyama-san, Stephen, Funada-san, Peter Starr and Itoh-san reported the observation. According to the data from the last three days, the object has a superhump period of ~0.048(1)d. Further observations during this phase are very important. The current magnitude is ~14mag. best regard, Kyoto University master's grade 2 Hiromasa Hoke

2 1

[vsnet-outburst 31694] TCP J02191736+2857158: possible growing superhump
by Keisuke Isogai 24 Jul '26

24 Jul '26

TCP J02191736+2857158: possible growing superhump Stephen M. Brincat and Itoh-san reported the observations. The object is now showing a possible growing superhump. The period is 0.0585 d, but it may be an alias. Further observations during this phase are very important. The current brightness is ~14 mag.

1 0

[vsnet-outburst 31693] TCP J20354364+6131329: early superhump
by Keisuke Isogai 22 Jul '26

22 Jul '26

TCP J20354364+6131329: early superhump Sahil Purabiya, Raul Michel Murillo, and Itoh-san reported the observations. The object is showing clear double-peaked early superhumps with a period of 0.0579(3) d and an amplitude of 0.03 mag. Thus, this object is undoubtedly a WZ Sge-type object. Judging from the light curve profile, this object would be discovered around the peak of the superoutburst. Continuous observations are encouraged.

1 0

[vsnet-outburst 31692] TCP J20354364+6131329: WZ Sge-type DN candidate
by Keisuke Isogai 20 Jul '26

20 Jul '26

TCP J20354364+6131329: WZ Sge-type DN candidate We posted the optical and spectroscopic observations of TCP J20354364+6131329 to ATel: https://www.astronomerstelegram.org/?read=17912 The large outburst amplitude of ~8 mag and the spectral features suggest that this object is a good candidate for a WZ Sge-type dwarf nova. This object is ~14.0 mag now. Follow-up observations are encouraged.

1 0

[vsnet-outburst 31691] Outbursts 18/07/2016
by Rod Stubbings 19 Jul '26

19 Jul '26

Outbursts 18/07/2026 object YYMMDD(UT) mag code remarks CHAST 260718.440 143 Stu.RASNZ outburst INDTU 260718.453 145 Stu.RASNZ outburst PAVAS 260718.403 153 Stu.RASNZ outburst TRADV 260718.599 130 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 31690] Re: TCPJ15030519+2202041: AM CVn-type dwarf novae
by Keisuke Isogai 18 Jul '26

18 Jul '26

This AM CVn star is ~16 mag now. Last night, this object was faint. So, this object is undergoing the next rebrightening. The typical duration of the rebrightening is about 1-2 days. Follow-up observations during the bright state and continuous monitoring are encouraged. On 2026/06/10 1:47, Josch Hambsch via vsnet-alert wrote: > Last night the target star reached mag 15.8 CV and I have switched to time series again from tonight onwards. Hopefully weather will cooperate. > > Regards, > > Josch > > Am 09.06.2026 um 13:20 schrieb Hiromasa Hoke via vsnet-alert: >> Itoh-san, Funada-san, Sano-san, Kubotera-san, Kirill Sokolovsky, Magnus Larsson, and Josch Hambsch have newly reported the observations. This object has finished its superoutburst. However, AM CVn-type dwarf novae characteristically show rebrigtening before reaching quiescence. Since it is uncertain when this object will re-bright, continuous observation is very important. >> >> Further continuous observations are strongly encouraged. Snapshots are also very welcome. >> >> best regard, >> Hiromasa Hoke >> >> On 2026/05/25 9:56, Hiromasa Hoke via vsnet-alert wrote: >>> TCPJ15030519+2202041: is still in quiescent interval before the second superoutburst >>> >>> Magnus Larsson, and Josch Hambsch have newly reported their observations. According to the data, this object is still in quiescent interval before the second superoutburst. AM CVn-type dwarf novae show the second outburst after an interval of several to more than ten days. Continued observations are encouraged to catch the onset of the second superoutburst. Thus, further snapshots are very welcome. >>> >>> best regard, >>> Hiromasa Hoke >>> >>> On 2026/05/21 17:02, Hiromasa Hoke via vsnet-alert wrote: >>>> TCPJ15030519+2202041: is still in quiescent interval before the second superoutburst >>>> >>>> Itoh-san, Moriyama-san, Hiraga-san, Funada-san, Magnus Larsson, and Josch Hambsch have newly reported their observations. According to the data, this object is still in quiescent interval before the second superoutburst. The current magnitude is 19~20. AM CVn-type dwarf novae show the second outburst after an interval of several to more than ten days. Continued observations are encouraged to catch the onset of the second superoutburst. >>>> >>>> best regard, >>>> Hiromasa Hoke >>>> >>>> On 2026/05/16 18:43, Hiromasa Hoke via vsnet-alert wrote: >>>>> TCPJ15030519+2202041: shows early superhump and rapid decay now >>>>> >>>>> Itoh-san, Moriyama-san, Hiraga-san, Funada-san, Magnus Larsson, and Josch Hambsch have newly reported their observations. According to the data, this object showed an early superhump with an amplitude of 0.03. Furthermore, this object has a superhump period of 0.03041(1). Now, this object shows rapid fading since May 15. AM CVn-type dwarf novae show the second outburst after an interval of several to more than ten days. This is a perfect opportunity to observe the growing superhump, so it is very important to observe this object even if it gets faint. >>>>> >>>>> best regard, >>>>> Hiromasa Hoke

1 0

[vsnet-outburst 31689] Outbursts 17/07/2026
by Rod Stubbings 18 Jul '26

18 Jul '26

Outbursts on 17/07/2026 object YYMMDD(UT) mag code remarks AQLV1141 260717.571 159 Stu.RASNZ outburst AQREG 260717.592 130 Stu.RASNZ outburst ARAAT 260717.389 132 Stu.RASNZ outburst ARAV793 260717.379 153 Stu.RASNZ outburst CAROQ 260717.401 145 Stu.RASNZ outburst CENMU 260717.443 132 Stu.RASNZ outburst CENNN 260717.448 142 Stu.RASNZ outburst CRABP 260717.441 140 Stu.RASNZ outburst ERICK 260717.599 140 Stu.RASNZ outburst ERIPS 260717.635 126 Stu.RASNZ outburst HYAAG 260717.363 144 Stu.RASNZ outburst PAVGS 260717.451 150 Stu.RASNZ outburst PSATY 260717.594 137 Stu.RASNZ outburst SERRY 260717.437 137 Stu.RASNZ outburst TUCVW 260717.463 158 Stu.RASNZ outburst ASASSN-14IK 260717.460 142 Stu.RASNZ outburst ASASSN-14JE 260717.375 146 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 31688] AT2026ryu: new SU UMa-type dwarf nova, likely WZ Sge-type
by Yusuke Tampo 15 Jul '26

15 Jul '26

AT2026ryu: new SU UMa-type dwarf nova, likely WZ Sge-type Rui Min et al discovered AT2026ryu at 14.98 mag on 2026-07-06 15:01:24 UTC. The outburst amplitude is ~8 mag. ZTF also discovered this object as ZTF26abeziup. https://www.wis-tns.org/object/2026ryu https://vsx.aavso.org/index.php?view=detail.top&oid=10875920 Lesedi telescope at SAAO and Itoh-san have reported the time-resolved observations of AT2026ryu. The most recent observations on 14 July with Lesedi show ordinary superhumps with a period of ~0.0571 d. No clear modulations are present in the data on 6 and 7 July. Thus AT 2026ryu is a new SU UMa-type dwarf nova. Given its large outburst amplitude and long waiting time before the emergence of ordinary superhumps, AT 2026ryu is likely a WZ Sge-type dwarf nova. Time-resolved observations are encouraged to improve the period determination. 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 31687] ASASSN-26ea: new SU UMa-type dwarf nova, likely WZ Sge-type
by Yusuke Tampo 15 Jul '26

15 Jul '26

ASASSN-26ea: new SU UMa-type dwarf nova ASASSN-26ea was discovered by ASASSN on 2026-07-5.07 at 16.67 mag. The time-resolved observations by Sjoerd Dufoer show ordinary superhumps with a period of ~0.058 d (other aliases possible). Thus ASASSN-26ea is a new SU UMa-type dwarf nova. Considering its large outburst amplitude (~8 mag according to the VSX) and short superhump period, ASASSN-26ea can be a WZ Sge-type dwarf nova. https://vsx.aavso.org/index.php?view=detail.top&oid=10875918 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 31686] ASASSN-26dv: new SU UMa-type dwarf nova and a candidate period bouncer
by Yusuke Tampo 15 Jul '26

15 Jul '26

ASASSN-26dv: new SU UMa-type dwarf nova and a candidate period bouncer ASASSN-26dv was discovered by ASASSN on 2026-06-23.03 UT at 14.62 mag. After the initial decline, ATLAS and ASASSN light curves showed a short dip around 2026-07-05 UT. https://vsx.aavso.org/index.php?view=detail.top&oid=10875895 The time-resolved observations after this dip by Berto Monard show likely positive superhumps, with a period of ~0.055 d. Thus, ASASSN-26dv is a new SU UMa-type dwarf nova with a possible dip in the outburst plateau, which is often seen in outbursts in period bouncers. Further time-resolved observations are encouraged to establish its superhump period. 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