September 2025 - vsnet-outburst - ooruri.kusastro.kyoto-u.ac.jp

[vsnet-outburst 31560] Outbursts 18/09/2025
by Rod Stubbings 19 Sep '25

19 Sep '25

Outbursts and selected activity. object YYMMDD(UT) mag code remarks AQLFO 250918.503 135 Stu.RASNZ active CAROQ 250918.691 139 Stu.RASNZ active CHAST 250918.687 136 Stu.RASNZ outburst CMADM 250918.703 146 Stu.RASNZ outburst ERIAH 250918.694 156 Stu.RASNZ active HYIWX 250918.483 120 Stu.RASNZ re-brightened superoutburst NORHP 250918.519 144 Stu.RASNZ active OCTAA 250918.571 148 Stu.RASNZ active OPHV2051 250918.499 143 Stu.RASNZ active ORIBI 250918.713 146 Stu.RASNZ active ORICN 250918.715 128 Stu.RASNZ active ORIV1159 250918.712 144 Stu.RASNZ outburst PEGHX 250918.660 139 Stu.RASNZ active PICVAR2008 250918.674 134 Stu.RASNZ outburst PYXVZ 250918.722 130 Stu.RASNZ outburst SERUZ 250918.552 129 Stu.RASNZ active TRADV 250918.525 128 Stu.RASNZ outburst NSV 35 250918.565 151 Stu.RASNZ outburst DDE 76 250918.677 140 Stu.RASNZ outburst DDE 77 250918.519 138 Stu.RASNZ active MASTER OT J142023.47-485540.0 250918.493 135 Stu.RASNZ active * WX Hyi went into outburst on 14/09/2025. Never fully faded and now re-brightened. Looks like a superoutburst. HYIWX 250914.475 123 HYIWX 250915.478 130 HYIWX 250917.458 138 HYIWX 250918.483 120 -- 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 31559] Outbursts 17/09/2025
by Rod Stubbings 19 Sep '25

19 Sep '25

Outbursts and selected activity. object YYMMDD(UT) mag code remarks AQLFO 250917.441 135 Stu.RASNZ outburst AQRQU 250917.423 160 Stu.RASNZ outburst CAROQ 250917.658 138 Stu.RASNZ active CHAST 250917.472 143 Stu.RASNZ active ERIAH 250917.635 147 Stu.RASNZ active HYIWX 250917.458 138 Stu.RASNZ active NORHP 250917.475 140 Stu.RASNZ outburst OCTAA 250917.467 148 Stu.RASNZ active OPHV2051 250917.481 139 Stu.RASNZ active ORIBI 250917.676 146 Stu.RASNZ outburst ORICN 250917.678 128 Stu.RASNZ active PAVGS 250917.630 153 Stu.RASNZ active PEGHX 250917.521 134 Stu.RASNZ active PICVAR2008 250917.640 <154 Stu.RASNZ SERUZ 250917.509 128 Stu.RASNZ active SGRV730 250917.506 140 Stu.RASNZ outburst NSV 11274 250917.599 156 Stu.RASNZ active DDE 77 250917.585 138 Stu.RASNZ active MASTER OT J142023.47-485540.0 250917.399 134 Stu.RASNZ outburst TCP J21091443-0917104 250917.419 153 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 31558] Outbursts 14/09/2025
by Rod Stubbings 15 Sep '25

15 Sep '25

Outbursts and selected activity observed. object YYMMDD(UT) mag code remarks AQLFO 250914.488 146 Stu.RASNZ active ARAV793 250914.514 149 Stu.RASNZ active CAROQ 250914.415 138 Stu.RASNZ outburst CENMU 250914.394 131 Stu.RASNZ outburst CENV342 250914.394 149 Stu.RASNZ outburst CENV1040 250914.403 132 Stu.RASNZ outburst CHAST 250914.641 143 Stu.RASNZ active CMAPU 250914.715 118 Stu.RASNZ outburst ERIAH 250914.673 136 Stu.RASNZ active HYIWX 250914.475 123 Stu.RASNZ outburst OCTAA 250914.472 148 Stu.RASNZ active OPHV2051 250914.501 133 Stu.RASNZ outburst ORICN 250914.705 126 Stu.RASNZ active PAVGS 250914.628 146 Stu.RASNZ active PEGHX 250914.683 129 Stu.RASNZ active PUPUY 250914.722 136 Stu.RASNZ outburst PUPBX 250914.721 150 Stu.RASNZ outburst SCOV478 250914.520 154 Stu.RASNZ active SERRY 250914.506 148 Stu.RASNZ outburst SERUZ 250914.546 139 Stu.RASNZ outburst TUCVW 250914.468 158 Stu.RASNZ active VOLSY 250914.414 146 Stu.RASNZ outburst NSV 11274 250914.613 141 Stu.RASNZ outburst DDE 77 250914.539 134 Stu.RASNZ outburst TCP J21091443-0917104 250914.437 147 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 31557] Outbursts 14/09/2025
by Rod Stubbings 14 Sep '25

14 Sep '25

Outbursts detected on 14/09/2025 object YYMMDD(UT) mag code remarks ARAV793 250913.619 149 Stu.RASNZ outburst ERIAH 250913.701 142 Stu.RASNZ outburst OCTAA 250913.699 148 Stu.RASNZ outburst ORICN 250913.709 127 Stu.RASNZ outburst PAVGS 250913.679 150 Stu.RASNZ outburst TUCVW 250913.693 156 Stu.RASNZ outburst ASASSN-14JE 250913.653 150 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 31556] ASASSN-25dt: new SU UMa-type dwarf nova
by tonny.vanmunster＠gmail.com 12 Sep '25

12 Sep '25

Dear colleagues, ASASSN-25dt was discovered by the ASAS-SN Survey (Ohio State University) on 2025 Sep 05.3 at mag 14.5 V/g. The quiescent counterpart is a 20.1 g mag Pan-STARRS1 object, implying an outburst amplitude of ~5-6 mag. I have just completed the analysis of my unfiltered CCD observations of ASASSN-25dt, obtained on 2025 Sep 10/11 and Sep 11/12 at CBA Extremadura Observatory. The data were acquired under (mostly) clear skies with a 0.40-m f/5.1 telescope and a Moravian G2-4000 CCD. The Sep 10/11 light curve showed only irregular, small-amplitude variability. However, the Sep 11/12 light curve clearly exhibits superhump modulations with an amplitude of 0.27 mag. Period analysis with ANOVA, Lomb-Scargle, Generalized-Lomb-Scargle and PDM methods (Peranso 3.1) yields a combined superhump period of 0.0605 +/- 0.0008d. The object was measured at mag CV = 15.9 on Sep 12th. Image calibration and photometry were carried out with the latest release of Phoranso. These results establish ASASSN-25dt as a new SU UMa-type dwarf nova. Follow-up observations are encouraged. 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

[vsnet-outburst 31555] TCP J21091443-0917104 (=ASASSN-25dq): new SU UMa-type dwarf nova
by Yusuke Tampo 08 Sep '25

08 Sep '25

TCP J21091443-0917104 (=ASASSN-25dq): new SU UMa-type dwarf nova NMW Survey discovered TCP J21091443-0917104 at 12.4 mag on 2025 08 22.8877 UCT. They suspected it could be a new UV Cet star based on its coincidence with the bright Gaia object (Gaia DR3 6896395696896704000; G=14.44, Plx=3.12 +/-0.04 mas). https://vsx.aavso.org/index.php?view=detail.top&oid=10867963 http://www.cbat.eps.harvard.edu/unconf/followups/J21091443-0917104.html S. Brincat and J. Hambsch have reported the time-resolved observations. Combining the observations by W. Goltz on AAVSO, I obtained a single-peak variation with a period of 0.05887(3) d, from the outburst maximum. ZTF light curve also shows a slow decline over the last two weeks, which is unlike a UV Cet star but agrees with a dwarf nova outburst. https://alerce.online/object/ZTF21abtlwbr Thus TCP J21091443-0917104 is most likely a new SU UMa-type dwarf nova. Considering its relatively short superhump period and expected large amplitude of outburst, the Gaia object can be a foreground star. The object is currently g=14.2 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

2025

2024

2023

2022

2021

vsnet-outburst September 2025