2025aico | Transient Name Server

RA/DEC (2000)

11:29:16.364 +20:35:08.26

172.3181846 +20.585629

Type

SN IIb

Redshift

0.00455

Discovery Report Classification Report

Reporting Group

GOTO

Discovering Data Source

GOTO

Discovery Date

2025-12-24 04:50:58.848

TNS AT

Public

Discovery Mag

16.86

Filter

L-GOTO

Reporter/s

D. O'Neill, K. Ackley, M. Dyer, J. Lyman, K. Ulaczyk, D. Steeghs, D. Galloway, V. Dhillon, P. O'Brien, G. Ramsay, K. Noysena, R. Kotak, R. Breton, J. Casares, L. Nuttall, R. Starling, B. Gompertz, B. Godson, T. Killestein, A. Kumar, M. Pursiainen, on behalf of GOTO collaboration

NED SIMBAD DECaLS PanSTARRS-1 SkyMapper VizieR WISE DSS ADS

Light curves

Pointer position (MJD, Mag, Abs.Mag): (0.00, 0.00, 0.00)

Spectra

Select	ID	Obs-date (UT)	Tel / Inst	Exp-Time	Observer/s	Reducer/s	Group	Spectrum ascii file	Spectrum fits file	Spec. Type	Remarks
	22798	2026-01-16 12:57:51	MMT / BINOSPEC		MMT Queue Observers	Nabeel Rehemtulla	ZTF	tns_2025aico_2461057.04017361_MMT_BINOSPEC_ZTF.ascii		Object
Binning factor: (rounded to nearest integer >1) Mouse hovers at WL: 0 (rest), 0 (observed) ▌Show H at z=v_exp= km/s ▌Show He at z=v_exp= km/s ▌Show He II at z=v_exp= km/s ▌Show C II at z=v_exp= km/s ▌Show C III at z=v_exp= km/s ▌Show C IV at z=v_exp= km/s ▌Show N II at z=v_exp= km/s ▌Show N III at z=v_exp= km/s ▌Show N IV at z=v_exp= km/s ▌Show N V at z=v_exp= km/s ▌Show O at z=v_exp= km/s ▌Show [O I] at z=v_exp= km/s ▌Show O II at z=v_exp= km/s ▌Show [O II] at z=v_exp= km/s ▌Show [O III] at z=v_exp= km/s ▌Show O V at z=v_exp= km/s ▌Show O VI at z=v_exp= km/s ▌Show Na at z=v_exp= km/s ▌Show Mg at z=v_exp= km/s ▌Show Mg II at z=v_exp= km/s ▌Show Si II at z=v_exp= km/s ▌Show S II at z=v_exp= km/s ▌Show Ca II at z=v_exp= km/s ▌Show [Ca II] at z=v_exp= km/s ▌Show Fe II at z=v_exp= km/s ▌Show Fe III at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Tellurics ▌Show Galaxy lines at z= ▌Show WR-WN at z=v_exp= km/s ▌Show WR-WC/O at z=v_exp= km/s Remarks
	22686	2025-12-25 14:57:52	Gemini-N / GMOS	600	D. Hung, J. Berghuis	J. Andrews	PASSTA	tns_2025aico_2025-12-25_14-57-51.5_Gemini-N_GMOS_PASSTA.txt	tns_2025aico_2025-12-25_14-57-51.5_Gemini-N_GMOS_PASSTA.fits	Object	Chip gaps still present in spectrum as they were unfortunately placed on NaiD and strong absorption, making mitigation difficult.
Binning factor: (rounded to nearest integer >1) Mouse hovers at WL: 0 (rest), 0 (observed) ▌Show H at z=v_exp= km/s ▌Show He at z=v_exp= km/s ▌Show He II at z=v_exp= km/s ▌Show C II at z=v_exp= km/s ▌Show C III at z=v_exp= km/s ▌Show C IV at z=v_exp= km/s ▌Show N II at z=v_exp= km/s ▌Show N III at z=v_exp= km/s ▌Show N IV at z=v_exp= km/s ▌Show N V at z=v_exp= km/s ▌Show O at z=v_exp= km/s ▌Show [O I] at z=v_exp= km/s ▌Show O II at z=v_exp= km/s ▌Show [O II] at z=v_exp= km/s ▌Show [O III] at z=v_exp= km/s ▌Show O V at z=v_exp= km/s ▌Show O VI at z=v_exp= km/s ▌Show Na at z=v_exp= km/s ▌Show Mg at z=v_exp= km/s ▌Show Mg II at z=v_exp= km/s ▌Show Si II at z=v_exp= km/s ▌Show S II at z=v_exp= km/s ▌Show Ca II at z=v_exp= km/s ▌Show [Ca II] at z=v_exp= km/s ▌Show Fe II at z=v_exp= km/s ▌Show Fe III at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Tellurics ▌Show Galaxy lines at z= ▌Show WR-WN at z=v_exp= km/s ▌Show WR-WC/O at z=v_exp= km/s Remarks Chip gaps still present in spectrum as they were unfortunately placed on NaiD and strong absorption, making mitigation difficult.
	22687	2025-12-25 08:03:14	SOAR / Goodman		R. Cartier/SOAR team	R. Cartier	None	tns_2025aico_2025-12-25_08-03-14_SOAR_Goodman_None.txt		Object
Binning factor: (rounded to nearest integer >1) Mouse hovers at WL: 0 (rest), 0 (observed) ▌Show H at z=v_exp= km/s ▌Show He at z=v_exp= km/s ▌Show He II at z=v_exp= km/s ▌Show C II at z=v_exp= km/s ▌Show C III at z=v_exp= km/s ▌Show C IV at z=v_exp= km/s ▌Show N II at z=v_exp= km/s ▌Show N III at z=v_exp= km/s ▌Show N IV at z=v_exp= km/s ▌Show N V at z=v_exp= km/s ▌Show O at z=v_exp= km/s ▌Show [O I] at z=v_exp= km/s ▌Show O II at z=v_exp= km/s ▌Show [O II] at z=v_exp= km/s ▌Show [O III] at z=v_exp= km/s ▌Show O V at z=v_exp= km/s ▌Show O VI at z=v_exp= km/s ▌Show Na at z=v_exp= km/s ▌Show Mg at z=v_exp= km/s ▌Show Mg II at z=v_exp= km/s ▌Show Si II at z=v_exp= km/s ▌Show S II at z=v_exp= km/s ▌Show Ca II at z=v_exp= km/s ▌Show [Ca II] at z=v_exp= km/s ▌Show Fe II at z=v_exp= km/s ▌Show Fe III at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Å at z=v_exp= km/s ▌Show Tellurics ▌Show Galaxy lines at z= ▌Show WR-WN at z=v_exp= km/s ▌Show WR-WC/O at z=v_exp= km/s Remarks

Light Curves

Filter

Tel / Inst

Obs-date range

JD Range

Photometry

wide-ATLAS

ATLAS-TDO_ATLAS-05

2025-12-20 04:37:59 - 2025-12-26 03:34:55

2461029.69304 - 2461035.64925

Photometry

ID	Obs-date	JD	Mag. / Flux	Err	Lim. Mag./Flux	Units	Filter	Tel / Inst	Exp-time	Observer/s	Remarks
542683	2025-12-26 03:34:55	2461035.64925	17.407	0.028	19.96	ABMag	wide-ATLAS	ATLAS-TDO_ATLAS-05	30	Robot
542682	2025-12-20 04:37:59	2461029.69304			20.01	ABMag	wide-ATLAS	ATLAS-TDO_ATLAS-05	30	Robot	[Last non detection]

Clear-

LAST_LAST-Cam

2024-03-03 22:28:49 - 2026-01-18 02:14:41

2460373.43668 - 2461058.59353

Photometry

ID	Obs-date	JD	Mag. / Flux	Err	Lim. Mag./Flux	Units	Filter	Tel / Inst	Exp-time	Observer/s	Remarks
551118	2026-01-18 02:14:41	2461058.59353	16.21			ABMag	Clear-	LAST_LAST-Cam	380
551117	2024-03-03 22:28:49	2460373.43668			21.93	ABMag	Clear-	LAST_LAST-Cam	400		[Last non detection]

L-GOTO

GOTO-N_GOTO-1

2025-12-23 04:20:54 - 2025-12-24 04:50:59

2461032.681175 - 2461033.702066

Photometry

ID	Obs-date	JD	Mag. / Flux	Err	Lim. Mag./Flux	Units	Filter	Tel / Inst	Exp-time	Observer/s	Remarks
542286	2025-12-24 04:50:59	2461033.702066	16.86	0.01		ABMag	L-GOTO	GOTO-N_GOTO-1	180
542285	2025-12-23 04:20:54	2461032.681175			20.3	ABMag	L-GOTO	GOTO-N_GOTO-1	180		[Last non detection]

r-ZTF

P48_ZTF-Cam

2025-12-22 12:41:05 - 2025-12-22 12:41:05

2461032.0285301 - 2461032.0285301

Photometry

ID	Obs-date	JD	Mag. / Flux	Err	Lim. Mag./Flux	Units	Filter	Tel / Inst	Exp-time	Observer/s	Remarks
544547	2025-12-22 12:41:05	2461032.0285301			20.1973	ABMag	r-ZTF	P48_ZTF-Cam			[Last non detection]

g-ZTF

P48_ZTF-Cam

2025-12-29 10:13:03 - 2025-12-29 10:13:03

2461038.9257292 - 2461038.9257292

Photometry

ID	Obs-date	JD	Mag. / Flux	Err	Lim. Mag./Flux	Units	Filter	Tel / Inst	Exp-time	Observer/s	Remarks
544548	2025-12-29 10:13:03	2461038.9257292	17.778	0.0707011		ABMag	g-ZTF	P48_ZTF-Cam

AT Reports

ID	Time received (UT)	Sender	Reporter/s	Reporting group	Disc. Data Source	RA	DEC	Discovery date (UT)	Discovery Mag.	Filter	AT Type	Internal name	Assoc. Groups	ADS Bibcode	Unreal
287702	2026-01-18 04:53:06	LAST_Bot1	E. O. Ofek (WIS),R. Konno (WIS),E. A. Zimmerman (WIS) et al.	LAST	LAST	11:29:16.318	+20:35:08.35	2026-01-18 02:14:40.992	16.21	Clear-	PSN		LAST		N
283493	2025-12-29 10:42:34	Fritz	Jesper Sollerman (SU),Christoffer Fremling (Caltech),Daniel Perley (LJMU) et al.	ZTF	ZTF	11:29:16.364	+20:35:08.26	2025-12-29 10:13:03.002	17.778	g-ZTF	PSN	ZTF25ackyfnb	ZTF		N
282349	2025-12-26 15:08:18	ATLAS_Bot1	J. Tonry,L. Denneau,H. Weiland (IfA et al.	ATLAS	ATLAS	11:29:16.357	+20:35:08.53	2025-12-26 03:34:55.200	17.407	wide-ATLAS	PSN	ATLAS25qfv	ATLAS		N
282146	2025-12-24 11:04:49	GOTO_bot	D. O'Neill,K. Ackley,M. Dyer et al.	GOTO	GOTO	11:29:16.362	+20:35:08.41	2025-12-24 04:50:58.848	16.86	L-GOTO	Other	GOTO25mmu	GOTO	2025TNSTR5147....1O	N

Classification Reports

Time received (UT)

Sender

Classifier/s

Group

Classification

Redshift

Spectra

Related files

Assoc. Groups

End prop. period

Remarks

ADS Bibcode

22797

2026-01-16 20:58:19

Nabeel Rehemtulla

Nabeel Rehemtulla on behalf of the ZTF collaboration

ZTF

SN IIb

0.00455

ZTF

Reverting classification to SN IIb following detection of helium features in MMT/Binospec spectrum

2026TNSCR.196....1R

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
22798	2026-01-16 12:57:51	MMT / BINOSPEC		MMT Queue Observers	Nabeel Rehemtulla	ZTF	tns_2025aico_2461057.04017361_MMT_BINOSPEC_ZTF.ascii		Object

22686

2025-12-26 00:50:20

Regis Cartier

R. Cartier, S. Kaur, C. Cardenas, G. Wilnkeljohann (CITEVA), E. Hueichapan, J. L. Prieto (UDP)

None

SN II

0.00478

Redshift from host galaxy narrow Halpha emission line in the 2D spectrum.

2025TNSCR5178....1C

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
22687	2025-12-25 08:03:14	SOAR / Goodman		R. Cartier/SOAR team	R. Cartier	None	tns_2025aico_2025-12-25_08-03-14_SOAR_Goodman_None.txt		Object

22685

2025-12-26 00:36:24

Jennifer Andrews

Jennifer Andrews (Gemini-N/NOIRLab), B. Hsu (U of Arizona), M. Shrestha (Monash U), D. Sand (U of Arizona), and Azalee Bostroem (U of Arizona) on behalf of the PASSTA collaboration

PASSTA

SN IIb

0.00455

DLT40, PASSTA

We report the classification of SN 2025aico as a young SN IIb based on optical spectra obtained on 2025-12-25 using the GMOS spectrograph on the Gemini-N telescope from Gemini Large and Long Programs (GN-LP-112). This target was classified using GELATO (Harutyunyan et al. 2008) and provided a best match to SN 1993J and SN 2013df at z=0.00455. We encourage follow-up spectroscopy. For more information on the Public AEON Spectroscopic Survey for Transient Astronomy (PASSTA), visit astro-passta.github.io or Astronote 2025-280.

2025TNSCR5179....1A

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
22686	2025-12-25 14:57:52	Gemini-N / GMOS	600	D. Hung, J. Berghuis	J. Andrews	PASSTA	tns_2025aico_2025-12-25_14-57-51.5_Gemini-N_GMOS_PASSTA.txt	tns_2025aico_2025-12-25_14-57-51.5_Gemini-N_GMOS_PASSTA.fits	Object			Chip gaps still present in spectrum as they were unfortunately placed on NaiD and strong absorption, making mitigation difficult.

Comments

Object coordinates updated

Object coordinates updated according to AT-report 283493 of Group ZTF
Previous RA, DEC: 11:29:16.357, +20:35:08.53 (172.31815625, +20.5857025)
Updated RA, DEC: 11:29:16.364, +20:35:08.26 (172.3181846, +20.585629)

Object coordinates updated

Object coordinates updated according to AT-report 282349 of Group ATLAS
Previous RA, DEC: 11:29:16.362, +20:35:08.41 (172.318174, +20.58567)
Updated RA, DEC: 11:29:16.357, +20:35:08.53 (172.31815625, +20.5857025)