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

[vsnet-outburst 31699] TCP J02191736+2857158: rebrightening
by Keisuke Isogai 31 Aug '26

31 Aug '26

TCP J02191736+2857158: rebrightening As expected, this object is now showing a rebrightening. The peak brightness should be ~15.0-14.8 mag. The rebrightening will be long-duration or multiple-type. Further observations are strongly encouraged. The observations are reported by Josch Hambsch, David Messier, Filipp Romanov, Hubert Delafay, Pavol A. Dubovsky, Moriyama-san, Sano-san, Itoh-san, and Stephen M. Brincat. On 2026/08/05 2:29, Hiromasa Hoke via vsnet-alert wrote: > dear all, > > This object was at ~16 mag around BJD 2461257.5 and is expected to have entered a rapid fading phase. However, similar objects have shown rebrightening, and a similar rebrightening is predicted for this object within the next 2–3 days. Continued follow-up observations are highly encouraged. > > On 2026/07/25 9:16, Keisuke Isogai via vsnet-alert wrote: >>> the object has a superhump period of ~0.048(1)d. >> This period of 69 min is below the period minimum. This value and the strong helium-rich spectrum, which we reported to ATel, suggest that this object is an EI Psc-type object showing a WZ Sge-type superoutburst. Such an event is very rare. Further observations are encouraged. >> >> On 2026/07/24 20:24, Hiromasa Hoke via vsnet-alert wrote: >>> 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

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[vsnet-outburst 31703] TCP J18030904+1218140= ZTF18absdcuk: large-amplitude CV outburst, possibly AM CVn-type?
by Yusuke Tampo 31 Aug '26

31 Aug '26

TCP J18030904+1218140= ZTF18absdcuk: large-amplitude CV outburst, possibly AM CVn-type? TCP J18030904+1218140 was discovered by Yuji Nakamura on 2026-08-19.5199 UT at 14.9 mag. Its previous outburst and log decline in 2018 were detected as ZTF18absdcuk. The VSX lists the r=21.1 mag star as the quiescent counterpart; thus the outburst amplitude is ~6 mag. https://alerce.online/object/ZTF18absdcuk https://vsx.aavso.org/index.php?view=detail.top&oid=10875986 Sano-san has reported the time-resolved observations for ~1.5 hours on 2026-08-20 UT. The light curve shows possible modulations with a period of 0.0288 d (41.5 min) with a double-peaked profile (early superhumps?). The optical spectrum obtained by the SAAO Lesedi telescope on 2026-08-19 UT shows a blue continuum with no prominent emission or absorption lines. Time-resolved photometry is strongly encouraged to confirm the periodicity and determine whether this is an AM CVn star or not. Best regards, Yusuke -- ---------------------------------------------- Yusuke TAMPO / 反保雄介 Postdoc fellow South African Astronomical Observatory / University of Cape Town EMAIL: tampo(a)kusastro.kyoto-u.ac.jp ALT. EMAIL: yusuke(a)saao.ac.za ----------------------------------------------

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[vsnet-outburst 31712] Outbursts 29/08/2026
by Rod Stubbings 29 Aug '26

29 Aug '26

Outbursts 29/08/2026 object YYMMDD(UT) mag code remarks CHAST 260829.393 135 Stu.RASNZ outburst HYIWX 260829.421 140 Stu.RASNZ outburst INDTU 260829.391 143 Stu.RASNZ outburst SGRV730 260829.413 146 Stu.RASNZ outburst LMC V3434 260829.375 142 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/

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[vsnet-outburst 31710] Activity (2026-08-25,26)
by Hiroyuki Maehara 26 Aug '26

26 Aug '26

Visual magnitude estimates by VSOLJ members object YYYYMMDD(UT) mag code CYGSS 20260824.541 <114 Mhh.VSOLJ CYGSS 20260825.509 110 Mhh.VSOLJ CYGSS 20260826.522 91 Mhh.VSOLJ SGEV488 20260825.506 71 Mhh.VSOLJ SGEV488 20260826.516 71 Mhh.VSOLJ Observer: Hiroyuki Maehara (Okayama, Japan) Instruments: 8cmR, 4.2cmB(10x)

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[vsnet-outburst 31709] SCOV390 brightening
by Tadashi Kojima 25 Aug '26

25 Aug '26

object YYYYMMDD(UT) mag SCOV390 20260615.677 137 SCOV390 20260810.447 129 SCOV390 20260825.437 120 Observer: Tadashi Kojima (Tsumagoi,Gunma, Japan) Instruments:fl=300mm lens+Canon EOS6D digital camera

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[vsnet-outburst 31708] ATel #18008; Spectroscopic Observation of PNV J19450648+1822422: Likely a Classical Nova?
by Yusuke Tampo 25 Aug '26

25 Aug '26

ATel #18008; Spectroscopic Observation of PNV J19450648+1822422: Likely a Classical Nova? From ATel; https://www.astronomerstelegram.org/?read=18008 PNV J19450648+1822422 was originally discovered by the NMW-TexasTech survey. Its position coincides with a known eclipsing binary candidate in Gaia, with an orbital period of 9.9011 d. Thus, time-resolved observations may reveal eclipses during its decline as the photosphere recedes. http://www.cbat.eps.harvard.edu/unconf/followups/J19450648+1822422.html https://vsx.aavso.org/index.php?view=detail.top&oid=10762522 See also the case of U Sco and its eclipses during the nova eruption; Muraoka et al 2024 https://arxiv.org/abs/2402.06347 Best regards, Yusuke -- ---------------------------------------------- Yusuke TAMPO / 反保雄介 Postdoc fellow South African Astronomical Observatory / University of Cape Town EMAIL: tampo(a)kusastro.kyoto-u.ac.jp ALT. EMAIL: yusuke(a)saao.ac.za ----------------------------------------------

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[vsnet-outburst 31701] ASASSN-26ew: new SU UMa-type dwarf nova, possibly WZ Sge-type
by Yusuke Tampo 24 Aug '26

24 Aug '26

ASASSN-26ew: new SU UMa-type dwarf nova, possibly WZ Sge-type ASASSN reported the discovery of ASASSN-26ew at 14.73 mag on 2026-08-13.82 UT. The archival ASASSN light curve shows that this had the outburst maximum on 2026-08-07.9 UT around 13.7 mag. The likely counterpart is the Bj=22.2 mag star in the GSC v2.4.2 catalogue; thus the outburst amplitude is ~8.5 mag. https://vsx.aavso.org/index.php?view=detail.top&oid=10875981 The SAAO Lesedi telescope observed ASASSN-26ew on 2026-08-18 and 2026-08-19. The light curve shows clear ordinary superhumps with a period of 0.05677(3) d and an amplitude of 0.15 mag. Thus ASASSN-26ew is a new SU UMa-type dwarf nova. Given its short superhump period and large outburst amplitude, this is a good candidate for a WZ Sge-type dwarf nova. The optical spectrum, also observed with the Lesedi telescope on 2026-08-18 UT, shows the Balmer absorption lines and superposed narrow emission core in Hα. Follow-up observations are encouraged. Best regards, Yusuke -- ---------------------------------------------- Yusuke TAMPO / 反保雄介 Postdoc fellow South African Astronomical Observatory / University of Cape Town EMAIL: tampo(a)kusastro.kyoto-u.ac.jp ALT. EMAIL: yusuke(a)saao.ac.za ----------------------------------------------

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[vsnet-outburst 31704] Outbursts 23/08 2026
by Rod Stubbings 23 Aug '26

23 Aug '26

Outbursts 23/08/2026 object YYMMDD(UT) mag code remarks CAPSY 260823.400 132 Stu.RASNZ outburst CENMU 260823.413 129 Stu.RASNZ outburst CENV342 260823.412 146 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/

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[vsnet-outburst 31702] Outbursts 20/08/2026
by Rod Stubbings 21 Aug '26

21 Aug '26

Outbursts 20/08/2026 object YYMMDD(UT) mag code remarks ERILT 260820.719 155 Stu.RASNZ outburst PAVGS 260820.696 155 Stu.RASNZ outburst NSV 11274 260820.695 155 Stu.RASNZ outburst SSS 100511:061754-362655 260820.729 153 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/

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[vsnet-outburst 31700] MAXI J1750-327: X-ray nova outburst
by Keisuke Isogai 17 Aug '26

17 Aug '26

MAXI J1750-327: X-ray nova outburst According to ATels, the X-ray nova MAXI J1750-327, a possible black hole binary, is undergoing an outburst. An optical counterpart has also been detected in outburst. https://www.astronomerstelegram.org/?read=17963 https://www.astronomerstelegram.org/?read=17974 The following ATel reports the magnitudes of g ~ 18.3 and i ~ 16.3 on Aug 14. And the coordinates are 17:50:03.038 -32:42:45.43. https://www.astronomerstelegram.org/?read=17971 Time-series photometry may reveal modulations. Thus, follow-up observations are strongly encouraged. Because of the high extinction toward this Galactic-plane target, Rc- or Ic-band observations are recommended for small telescopes.

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