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

[vsnet-outburst 31522] Activity (2025-06-04)
by Hiroyuki Maehara 04 Jun '25

04 Jun '25

Visual magnitude estimates by VSOLJ members object YYYYMMDD(UT) mag code HERAH 20250604.542 130 Mhh.VSOLJ LYRAY 20250604.546 140 Mhh.VSOLJ UMASW 20250604.508 114 Mhh.VSOLJ Observer: Hiroyuki Maehara (Okayama, Japan) Instruments: 30cmL

1 0

[vsnet-outburst 31521] Outbursts 3-4 /06/2025
by Rod Stubbings 04 Jun '25

04 Jun '25

Outbursts and selected activity. object YYMMDD(UT) mag code remarks AQLDH 250604.571 127 Stu.RASNZ outburst AQLFO 250604.572 154 Stu.RASNZ active ARABF 250603.409 146 Stu.RASNZ outburst ARABF 250604.440 150 Stu.RASNZ active CAROQ 250603.405 144 Stu.RASNZ outburst CAROQ 250604.535 143 Stu.RASNZ active CENNN 250604.582 153 Stu.RASNZ active CENV342 250604.544 156 Stu.RASNZ active CENV485 250604.590 144 Stu.RASNZ superoutburst CHAST 250603.417 143 Stu.RASNZ active CHAST 250604.544 143 Stu.RASNZ active CMAHL 250603.379 116 Stu.RASNZ active INDTU 250604.559 143 Stu.RASNZ outburst MICCM 250604.560 149 Stu.RASNZ active OCTDT 250603.419 134 Stu.RASNZ superoutburst PICAR 250603.399 130 Stu.RASNZ outburst PICAR 250604.456 132 Stu.RASNZ active PUPBX 250603.385 142 Stu.RASNZ outburst PUPBX 250604.417 145 Stu.RASNZ active SCOV598 250603.410 153 Stu.RASNZ outburst SCOV598 250604.412 147 Stu.RASNZ active TRADV 250603.363 132 Stu.RASNZ outburst TRADV 250604.433 137 Stu.RASNZ active VIRQZ 250603.384 144 Stu.RASNZ active NSV 11274 250604.456 147 Stu.RASNZ outburst CRTS J124507.8-381322 250604.587 130 Stu.RASNZ active MASTER OT J142023.47-485540.0 250604.426 128 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 31520] Activity 03/04-06-2025
by Laslo Kočmaroš 04 Jun '25

04 Jun '25

Type of observation: Visual Instrument: Dobson 355/1650 Location: Zrenjanin, Serbia Object YYYYMMDD Mag Observer AQLKX 20250603.985 <14.0 Laszlo Kocsmaros BOOCR 20250603.817 <14.2 Laszlo Kocsmaros BOOTT 20250603.822 <14.3 Laszlo Kocsmaros BOOUZ 20250603.819 <14.3 Laszlo Kocsmaros CRBT 20250603.976 <9.8 Laszlo Kocsmaros CYG1504 20250604.017 <14.2 Laszlo Kocsmaros CYGEM 20250604.003 12.7 Laszlo Kocsmaros CYGSS 20250604.014 11.2 Laszlo Kocsmaros CYGV1028 20250604.023 <14.2 Laszlo Kocsmaros CYGV503 20250604.010 13.8 Laszlo Kocsmaros CYGV516 20250604.010 <14.2 Laszlo Kocsmaros CYGV632 20250604.015 <14.3 Laszlo Kocsmaros HERAH 20250603.844 12.6 Laszlo Kocsmaros HERV844 20250603.980 <14.1 Laszlo Kocsmaros LYRAY 20250603.835 13.6 Laszlo Kocsmaros LYRCY 20250603.935 <13.9 Laszlo Kocsmaros LYRLL 20250603.931 <14.2 Laszlo Kocsmaros MISV1448 20250604.026 <14.2 Laszlo Kocsmaros OPHV426 20250603.999 12.2 Laszlo Kocsmaros SGERZ 20250603.992 <14.4 Laszlo Kocsmaros VULVW 20250603.994 13.3 Laszlo Kocsmaros Regards, Laszlo Kocsmaros

1 0

[vsnet-outburst 31519] TCP J20131357+1154031: new SU UMa-type dwarf nova, possibly WZ Sge-type
by Yusuke Tampo 03 Jun '25

03 Jun '25

TCP J20131357+1154031: new SU UMa-type dwarf nova, possibly WZ Sge-type K. Itagaki discovered TCP J20131357+1154031 on 2025-05-19 UTC at 14.7 mag (unfiltered). The outburst amplitude is ~8.4 mag. https://www.aavso.org/vsx/index.php?view=detail.top&oid=10848625 SAAO/Lesedi telescope, Josch Hambsch, and Sano-san have reported the time-resolved observations. Josch's observations after 28 May show single-peaked variation with a period of 0.05797(6) d, likely an ordinary superhump. No clear modulations were presented before this. Thus TCP J20131357+1154031 is a new SU UMa-type dwarf nova and a good candidate for a WZ Sge-type dwarf nova, given its late appearance of ordinary superhumps. 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 31518] ASASSN-25ce: new WZ Sge-type dwarf nova
by Yusuke Tampo 02 Jun '25

02 Jun '25

ASASSN-25ce: new WZ Sge-type dwarf nova ASAS-SN discovered ASASSN-25ce on 2025-05-28 UTC at 12.26 mag. The Gaia counterpart is G~20.7 mag thus the outburst amplitude is ~8.5 mag. The SAAO team and Berto Monard reported the time-resolved observations. These light curves show a double-peak modulation with an amplitude of ~0.1 mag and a period of ~0.05537(1) d. The 5-sec resolution observations by the SAAO/Lesedi telescope also show QPO-like modulation with 5--10 min. Hence, ASASSN-25ce is a new WZ Sge-type dwarf nova, possibly with a relatively higher inclination, while no clear eclipses are present. Further 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 0

[vsnet-outburst 31517] Outbursts 31/05/2025
by Rod Stubbings 31 May '25

31 May '25

Outbursts and selected activity. object YYMMDD(UT) mag code remarks AQLFO 250531.611 137 Stu.RASNZ outburst CARQU 250531.670 158 Stu.RASNZ outburst CENNN 250531.609 144 Stu.RASNZ outburst CENV342 250531.588 144 Stu.RASNZ active CENV485 250531.599 142 Stu.RASNZ outburst CHAST 250531.454 145 Stu.RASNZ active CMAHL 250531.360 113 Stu.RASNZ active CNCGZ 250531.369 151 Stu.RASNZ active CRABP 250531.478 147 Stu.RASNZ outburst HYAV392 250531.580 148 Stu.RASNZ active LEOX 250531.371 126 Stu.RASNZ active MICCM 250531.615 149 Stu.RASNZ active MUSDQ 250531.607 152 Stu.RASNZ outburst NORHP 250531.380 132 Stu.RASNZ outburst OCTDT 250531.647 120 Stu.RASNZ outburst PAVAS 250531.483 150 Stu.RASNZ outburst PICAR 250531.433 131 Stu.RASNZ outburst PUPUY 250531.397 140 Stu.RASNZ active PUPCL 250531.425 152 Stu.RASNZ outburst PUPHO 250531.399 142 Stu.RASNZ active RETVAR2005 250531.358 136 Stu.RASNZ outburst SERUZ 250531.573 130 Stu.RASNZ outburst SERQW 250531.461 149 Stu.RASNZ active SGRV3774 250531.469 150 Stu.RASNZ outburst VIRQZ 250531.372 100 Stu.RASNZ outburst ASASSN-16GG 250531.639 139 Stu.RASNZ outburst ASASSN-20PV 250531.587 143 Stu.RASNZ outburst 2nd rebrightening. CRTS J124507.8-381322 250531.603 124 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 31516] ASASSN-25ca: new SU UMa-type dwarf nova
by Yusuke Tampo 30 May '25

30 May '25

ASASSN-25ca: new SU UMa-type dwarf nova ASAS-SN reported ASASSN-25ca on 2025-05-20 at g=14.1. https://www.aavso.org/vsx/index.php?view=detail.top&oid=10848671 Berto Monard and Josch Hambsch reported the time-resolved observations of ASASSN-25ca. Their observations on 29 May show ordinary superhumps with a period of 0.0588(1) d. Observations on 27 May also show a hint of superhumps but the baseline was too short. Thus, ASASSN-25ca is a new SU UMa-type dwarf nova, and could be a WZ Sge-type based on its short superhump period, large outburst amplitude, and lack of previous outbursts. 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 31515] ASASSN-25bz: new SU UMa-type dwarf nova
by Yusuke Tampo 28 May '25

28 May '25

ASASSN-25bz: new SU UMa-type dwarf nova ASASSN-25bz (=AT 2025lkr) was discovered at 14.8 mag on 20 May by ASAS-SN. The suggested outburst amplitude is ~8 mag according to the VSX. ASAS-SN reported to the TNS that this could be a classical nova based on its low Galactic latitude b~-2.0 deg. https://www.aavso.org/vsx/index.php?view=detail.top&oid=10848672 I obtained the time-resolved observations of ASASSN-25bz with the SAAO/Lesedi telescope on 26 and 27 May. Its light curve shows a prominent ordinary superhump with an amplitude of 0.15 mag and a period of ~0.0561(1) d (1-d aliases are possible). The optical spectrum obtained on 23 May with the SAAO/Lesedi telescope is dominated by Balmer absorption lines. Thus, I conclude that ASASSN-25bz is a new SU UMa-type dwarf nova. The system is around 15.6 mag. 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 31513] TCP J18513997+3522412: large-amplitude modulation, possibly eclipsing WZ Sge-type dwarf nova?
by Yusuke Tampo 27 May '25

27 May '25

TCP J18513997+3522412: large-amplitude modulation, possibly eclipsing WZ Sge-type dwarf nova? TCP J18513997+3522412 was discovered by Y. Nakamura on 22nd May at 13.7 mag (unfiltered). The counterpart star in Pan-STARRS1 is r~20.5 mag, and thus the outburst amplitude is 6.8 mag. http://www.cbat.eps.harvard.edu/unconf/followups/J18513997+3522412.html https://www.aavso.org/vsx/index.php?view=detail.top&oid=10848644 Sano-san reported the time-resolved observations of this object. Although the baseline was just one hour, the light curve shows a large-amplitude modulation of ~0.35 mag. This is likely either an ordinary superhump in a SU UMa-type dwarf nova or even a large-amplitude early superhump + eclipse in an eclipsing WZ Sge-type dwarf nova. Further time-resolved observations with longer baselines are encouraged. Best regards, Yusuke -- ---------------------------------------------- South African Astronomical Observatory, Postdoc fellow 反保雄介 Yusuke TAMPO MAIL: tampo(a)kusastro.kyoto-u.ac.jp MAIL: yusuke(a)saao.ac.za ----------------------------------------------

1 1

[vsnet-outburst 31512] TCP J02472889+6758170 = Gaia DR3 517539710877791488
by Yusuke Tampo 26 May '25

26 May '25

TCP J02472889+6758170 = Gaia DR3 517539710877791488 The NMW team discovered this transient at 13.0 mag (unfiltered), which is associated with the known variable star Gaia DR3 517539710877791488 with ~18.0 mag. They suggest that this could be an AM CVn star in outburst. Its blue color in the Pan-STARRS1 image also supports this suggestion, and TCP J02472889+6758170 is at least a CV in new outburst. http://www.cbat.eps.harvard.edu/unconf/followups/J02472889+6758170.html https://www.aavso.org/vsx/index.php?view=detail.top&oid=2841325 Time-resoved observations are encouraged. Best regards, Yusuke -- ---------------------------------------------- South African Astronomical Observatory, Postdoc fellow 反保雄介 Yusuke TAMPO MAIL: tampo(a)kusastro.kyoto-u.ac.jp MAIL: yusuke(a)saao.ac.za ----------------------------------------------

1 0