RA/DEC (2000)
23:20:30.538 +12:14:30.25
350.1272419 +12.2417361
Type
SLSN-I
Redshift
0.11
Related AstroNotes: 2025-277
Reporting Group
GOTO
Discovering Data Source
GOTO
Discovery Date
2025-08-28 23:50:06.432
TNS AT
Y
Public
Y
Discovery Mag
19.8
Filter
L-GOTO
Reporter/s
M. Pursiainen, G. Ramsay, K. Ackley, M. Dyer, J. Lyman, K. Ulaczyk, D. Steeghs, D. Galloway, V. Dhillon, P. O'Brien, K. Noysena, R. Kotak, R. Breton, J. Casares, L. Nuttall, B. Godson, T. Killestein, A. Kumar, D. O'Neill, on behalf of GOTO collaboration

Spectra

 SN_2025whv - 2025-09-04 02:33:01 LT / SPRAT (ZTF)z=
 SN_2025whv - 2025-08-31 03:54:08 NOT / ALFOSC (GOTO)z=
Show H at z=vexp= km/s
Show He at z=vexp= km/s
Show He II at z=vexp= km/s
Show C II at z=vexp= km/s
Show C III at z=vexp= km/s
Show C IV at z=vexp= km/s
Show N II at z=vexp= km/s
Show N III at z=vexp= km/s
Show N IV at z=vexp= km/s
Show N V at z=vexp= km/s
Show O at z=vexp= km/s
Show [O I] at z=vexp= km/s
Show O II at z=vexp= km/s
Show [O II] at z=vexp= km/s
Show [O III] at z=vexp= km/s
Show O V at z=vexp= km/s
Show O VI at z=vexp= km/s
Show Na at z=vexp= km/s
Show Mg at z=vexp= km/s
Show Mg II at z=vexp= km/s
Show Si II at z=vexp= km/s
Show S II at z=vexp= km/s
Show Ca II at z=vexp= km/s
Show [Ca II] at z=vexp= km/s
Show Fe II at z=vexp= km/s
Show Fe III at z=vexp= km/s
Show Å at z=vexp= km/s
Show Å at z=vexp= km/s
Show Å at z=vexp= km/s
Show Å at z=vexp= km/s
Show Tellurics 
Show Galaxy lines at z=
Show WR-WN at z=vexp= km/s
Show WR-WC/O at z=vexp= km/s
   Binning factor: (rounded to nearest integer >1)
Mouse hovers at WL: 0 (rest),0 (observed)

Light curves

 ATLAS-TDO_ATLAS-05_wide
 ATLAS-STH_ATLAS-03_cyan
 GOTO-N_GOTO-1_L
 P48_ZTF-Cam_r
 P48_ZTF-Cam_g
   
Pointer position (MJD, Mag, Abs.Mag): (0.00, 0.00, 0.00)
Spectra
ID Obs-date (UT) Tel / Inst Exp-Time Observer/s Reducer/s Group Spectrum ascii file Spectrum fits file Spec. Type Assoc. Groups End prop. period Remarks
21996 2025-09-04 02:33:01 LT / SPRAT 2000 LTRobot D. Perley ZTF tns_2025whv_2025-09-04_02-33-01_LT_SPRAT_ZTF.ascii Object
21933 2025-08-31 03:54:08 NOT / ALFOSC I. Worssam, M. Pursiainen I. Worssam, M. Pursiainen GOTO tns_2025whv_2025-08-31_03-54-08.072_NOT_ALFOSC_GOTO.dat Object
Light Curves
Filter Tel / Inst Obs-date range JD Range Photometry
wide-ATLAS ATLAS-TDO_ATLAS-05 2025-08-25 03:42:45 - 2025-08-25 03:42:45 2460912.65469 - 2460912.65469 1
Photometry
ID Obs-date JD Mag. / Flux Err Lim. Mag./Flux Units Filter Tel / Inst Exp-time Observer/s Remarks
514735 2025-08-25 03:42:45 2460912.65469 19.93 ABMag wide-ATLAS ATLAS-TDO_ATLAS-05 90 Robot [Last non detection]
cyan-ATLAS ATLAS-STH_ATLAS-03 2025-08-29 22:20:41 - 2025-08-29 22:20:41 2460917.43103 - 2460917.43103 1
Photometry
ID Obs-date JD Mag. / Flux Err Lim. Mag./Flux Units Filter Tel / Inst Exp-time Observer/s Remarks
514736 2025-08-29 22:20:41 2460917.43103 19.206 0.143 19.62 ABMag cyan-ATLAS ATLAS-STH_ATLAS-03 30 Robot
L-GOTO GOTO-N_GOTO-1 2025-08-27 23:50:53 - 2025-08-28 23:50:06 2460915.493671 - 2460916.493132 2
Photometry
ID Obs-date JD Mag. / Flux Err Lim. Mag./Flux Units Filter Tel / Inst Exp-time Observer/s Remarks
514115 2025-08-28 23:50:06 2460916.493132 19.8 0.2 ABMag L-GOTO GOTO-N_GOTO-1 180
514114 2025-08-27 23:50:53 2460915.493671 20 ABMag L-GOTO GOTO-N_GOTO-1 180 [Last non detection]
r-ZTF P48_ZTF-Cam 2025-07-31 08:57:41 - 2025-07-31 08:57:41 2460887.8733912 - 2460887.8733912 1
Photometry
ID Obs-date JD Mag. / Flux Err Lim. Mag./Flux Units Filter Tel / Inst Exp-time Observer/s Remarks
514858 2025-07-31 08:57:41 2460887.8733912 19.4794 0.0579654 ABMag r-ZTF P48_ZTF-Cam
g-ZTF P48_ZTF-Cam 2025-07-31 07:36:49 - 2025-09-01 08:00:27 2460887.8172338 - 2460919.8336458 2
Photometry
ID Obs-date JD Mag. / Flux Err Lim. Mag./Flux Units Filter Tel / Inst Exp-time Observer/s Remarks
514859 2025-09-01 08:00:27 2460919.8336458 18.694 0.0869422 ABMag g-ZTF P48_ZTF-Cam
514857 2025-07-31 07:36:49 2460887.8172338 20.9227 ABMag g-ZTF P48_ZTF-Cam [Last non detection]
AT Reports
ID Time received (UT) Sender Reporter/s Reporting group Disc. Data Source RA DEC Discovery date (UT) Discovery Mag. Filter Related files AT Type Host name Internal name Assoc. Groups End prop. period Remarks ADS Bibcode Unreal Auto classification
268914 2025-09-01 11:12:49 Fritz Jacob Wise (LJMU),Christoffer Fremling (Caltech),Daniel Perley (LJMU) et al. ZTF ZTF 23:20:30.538 +12:14:30.25 2025-07-31 08:57:40.999 19.4794 r-ZTF PSN ZTF25abmjfcf ZTF N
268853 2025-09-01 09:12:37 ATLAS_Bot1 J. Tonry,L. Denneau,H. Weiland et al. ATLAS ATLAS 23:20:30.533 +12:14:30.10 2025-08-29 22:20:40.992 19.206 cyan-ATLAS PSN ATLAS25kui ATLAS N
268570 2025-08-30 06:38:45 GOTO_bot M. Pursiainen,G. Ramsay,K. Ackley et al. GOTO GOTO 23:20:30.518 +12:14:30.03 2025-08-28 23:50:06.432 19.8 L-GOTO Other GOTO25gnw GOTO This transient was discovered with the assistance of the GOTO Kilonova Seekers Citizen Scientists on Zooniverse. The candidate was flagged by volunteers: Svetoslav Alexandrov, Mayahuel Torres Guerrero, M.T. Mazzucato, Henryk Krawczyk, Íris Eduarda Forcel Roncada 2025TNSTR3453....1P N
Classification Reports
ID Time received (UT) Sender Classifier/s Group Classification Redshift Spectra Related files Assoc. Groups End prop. period Remarks ADS Bibcode
21996 2025-09-08 17:55:28 ZTF_Bot1 J. Sollerman, D. Perley (LJMU), A. Mehla, M. Chu, K. R. Hinds, C. Fremling (Caltech) on behalf of the Zwicky Transient Facility (ZTF) ZTF SLSN-I 0.11 1 ZTF 2025TNSCR3621....1S
Spectra
ID Obs-date (UT) Tel / Inst Exp-Time Observer/s Reducer/s Group Spectrum ascii file Spectrum fits file Spec. Type Assoc. Groups End prop. period Remarks
21996 2025-09-04 02:33:01 LT / SPRAT 2000 LTRobot D. Perley ZTF tns_2025whv_2025-09-04_02-33-01_LT_SPRAT_ZTF.ascii Object
21933 2025-08-31 08:54:32 David O'Neill I. Worssam, M. Pursiainen, D. O'Neill, J. Lyman, T. Killestein, K. Ackley, M. Dyer, K. Ulaczyk, D. Steeghs, D. Galloway, V. Dhillon, P. O'Brien, G. Ramsay, K. Noysena, R. Kotak, R. Breton, J. Casares, L. Nuttall, B. Godson, A. Kumar on behalf of GOTO collaboration GOTO SN Ia-91T-like 0.1 1 GOTO Reasonable matches to SN Ia and SN Ia-91T-like at z~0.1. 91T-like matches are favoured owing to the template epochs being a closer approximation of the light curve (approaching peak), the inferred current absolute magnitude of M ~ -19.4 mag, and the relatively weak Si II. 2025TNSCR3484....1W
Spectra
ID Obs-date (UT) Tel / Inst Exp-Time Observer/s Reducer/s Group Spectrum ascii file Spectrum fits file Spec. Type Assoc. Groups End prop. period Remarks
21933 2025-08-31 03:54:08 NOT / ALFOSC I. Worssam, M. Pursiainen I. Worssam, M. Pursiainen GOTO tns_2025whv_2025-08-31_03-54-08.072_NOT_ALFOSC_GOTO.dat Object

Comments

TNS
System

Object coordinates updated

Object coordinates updated according to AT-report 268914 of Group ZTF
Previous RA, DEC: 23:20:30.533, +12:14:30.10 (350.12722, +12.2416945455)
Updated RA, DEC: 23:20:30.538, +12:14:30.25 (350.1272419, +12.2417361)

TNS
System

Object coordinates updated

Object coordinates updated according to AT-report 268853 of Group ATLAS
Previous RA, DEC: 23:20:30.518, +12:14:30.03 (350.127159, +12.241676)
Updated RA, DEC: 23:20:30.533, +12:14:30.10 (350.12722, +12.2416945455)