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

[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 ----------------------------------------------

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[vsnet-outburst 31554] Outbursts 24/08/2025
by Rod Stubbings 25 Aug '25

25 Aug '25

Detected outbursts on 24/08/2025 object YYMMDD(UT) mag code remarks ERIPS 250824.590 130 Stu.RASNZ outburst LUPBR 250824.529 145 Stu.RASNZ outburst SGRV729 250824.417 148 Stu.RASNZ outburst SGRV730 250824.417 148 Stu.RASNZ outburst SGRV1089 250824.418 140 Stu.RASNZ outburst SGRV2276 250824.413 156 Stu.RASNZ outburst SGRV3774 250824.574 149 Stu.RASNZ outburst ASASSN-14GR 250824.678 148 Stu.RASNZ outburst NSV 35 250824.557 150 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/

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[vsnet-outburst 31553] Outbursts 23/08/2025
by Rod Stubbings 24 Aug '25

24 Aug '25

Detected outbursts on 23/08/2025 object YYMMDD(UT) mag code remarks AQLFO 250823.586 137 Stu.RASNZ active AQLV1047 250823.589 150 Stu.RASNZ outburst ARAV793 250823.604 148 Stu.RASNZ outburst ERICK 250823.609 140 Stu.RASNZ outburst HYIWX 250823.611 138 Stu.RASNZ outburst HYIVW 250823.424 103 Stu.RASNZ outburst INDTU 250823.444 142 Stu.RASNZ outburst MENAD 250823.616 152 Stu.RASNZ outburst MUSDQ 250823.419 150 Stu.RASNZ outburst PAVV548 250823.452 138 Stu.RASNZ outburst SERQW 250823.412 148 Stu.RASNZ outburst ASASSN-14IK 250823.455 154 Stu.RASNZ outburst MASTER OT J142023.47-485540.0 250823.435 130 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/

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[vsnet-outburst 31552] Outbursts 19/08/2025
by Rod Stubbings 20 Aug '25

20 Aug '25

Detected outbursts on 19/08/2025 object YYMMDD(UT) mag code remarks CENV803 250819.462 143 Stu.RASNZ outburst HYIDR 250819.567 157 Stu.RASNZ outburst TRADV 250819.545 129 Stu.RASNZ outburst ASASSN-18XU 250819.554 140 Stu.RASNZ outburst NSV 35 250819.616 150 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/

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[vsnet-outburst 31551] Outbursts 18/08/2025
by Rod Stubbings 19 Aug '25

19 Aug '25

Detected outbursts on 18/08/2025 object YYMMDD(UT) mag code remarks CENV373 250818.385 132 Stu.RASNZ outburst CENV485 250818.427 154 Stu.RASNZ outburst SERUZ 250818.585 140 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 31550] Outbursts 17/08/2025
by Rod Stubbings 18 Aug '25

18 Aug '25

Detected outbursts on 17/08/2025 object YYMMDD(UT) mag code remarks APSV394 250817.626 147 Stu.RASNZ outburst CAROQ 250817.420 144 Stu.RASNZ outburst FORAY 250817.649 153 Stu.RASNZ outburst PAVAS 250817.670 150 Stu.RASNZ outburst PAVGS 250817.412 150 Stu.RASNZ outburst VELV383 250817.383 132 Stu.RASNZ outburst VIRHS 250817.377 144 Stu.RASNZ outburst VOLSY 250817.419 146 Stu.RASNZ outburst ASASSN-22GX 250817.615 147 Stu.RASNZ outburst NSV 11274 250817.392 145 Stu.RASNZ outburst DDE 77 250817.644 138 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 31549] Outbursts 13/08/2025
by Rod Stubbings 14 Aug '25

14 Aug '25

Detected outbursts on 13/08/2025 object YYMMDD(UT) mag code remarks AQLKX 250813.440 140 Stu.RASNZ outburst CENV342 250813.385 149 Stu.RASNZ outburst MENTU 250813.418 120 Stu.RASNZ outburst OCTDT 250813.448 132 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 31534] ASASSN-25dc; a new candidate of a WZ Sge-type dwarf nova with the double superoutburst
by Yusuke Tampo 13 Aug '25

13 Aug '25

ASASSN-25dc; a new candidate of a WZ Sge-type dwarf nova with the double superoutburst ASASSN-25dc was discovered by ASAS-SN on 2025-07-13.09 UTC at g=13.07. This outburst is also observed by ATLAS, o~15.2 mag on 2025-07-07.8 UTC and o~13.5 mag on 2025-07-10.9 UTC. The likely counterpart is Gaia DR3 6129070308813533568 with G~21.0 mag, hence the outburst amplitude is ~7.0 mag. This system underwent a short dip on 16-17th July, around 14.5 mag, and is now recovering from the dip. Lesedi telescope at Sutherland, Josch Hambsh, and Berto Monard have reported the time-resolved observations of ASASSN-25dc. PDM analysis using the overall data yields a single-peaked modulation with a period of 0.05991(4) d and an amplitude of 0.03 mag. Combining the 1-mag dip feature on the light curve and short superhump period, ASASSN-25dc can be a similar system to double-superoutburst WZ Sge-type dwarf novae, especially the period-bouncer candidates ASASSN-15jd and ASASSN-16hg (see Kimura et al. 2016,2018). https://arxiv.org/abs/1604.06344 https://arxiv.org/abs/1803.03179 The ongoing second outburst should show the evolution of ordinary superhumps. The hint of ordinary superhumps is seen in the observations on 17th July. 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 ----------------------------------------------

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[vsnet-outburst 31547] Outbursts 11/08/2025
by Rod Stubbings 12 Aug '25

12 Aug '25

Outbursts detected on 11/08/2025 object YYMMDD(UT) mag code remarks ARAAT 250811.502 140 Stu.RASNZ outburst INDTU 250811.404 153 Stu.RASNZ outburst ASASSN-14IK 250811.407 143 Stu.RASNZ outburst LMC V3434 250811.384 144 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 31546] Outbursts 10/08/2025
by Rod Stubbings 10 Aug '25

10 Aug '25

Detected outbursts tonight. object YYMMDD(UT) mag code remarks AQLUU 250810.506 120 Stu.RASNZ outburst ARAV793 250810.519 149 Stu.RASNZ outburst CENV436 250810.387 123 Stu.RASNZ outburst CENV442 250810.386 126 Stu.RASNZ outburst CRABP 250810.377 144 Stu.RASNZ outburst DELHO 250810.501 137 Stu.RASNZ outburst SCOV598 250810.373 148 Stu.RASNZ outburst SERUZ 250810.384 134 Stu.RASNZ outburst SGRV729 250810.372 141 Stu.RASNZ outburst SGRV1830 250810.382 126 Stu.RASNZ outburst TRADV 250810.517 130 Stu.RASNZ outburst ASASSN-14FE 250810.601 138 Stu.RASNZ outburst ASASSN-19CT 250810.388 142 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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