August 2025 - vsnet-grb-info - ooruri.kusastro.kyoto-u.ac.jp

[vsnet-grb-info 39566] LIGO/Virgo/KAGRA S250818k: GTC/OSIRIS Optical Detection of AT2025ulz
by GCN Circulars 22 Aug '25

22 Aug '25

TITLE: GCN CIRCULAR NUMBER: 41502 SUBJECT: LIGO/Virgo/KAGRA S250818k: GTC/OSIRIS Optical Detection of AT2025ulz DATE: 25/08/22 17:59:55 GMT FROM: Rosa L. Becerra at Tor Vergata, Roma <rosa.becerra(a)roma2.infn.it> Rosa L. Becerra (U Rome), Alan M. Watson (UNAM), and Eleonora Troja (U Rome) report on behalf of a larger team: We observed the field of AT2025ulz/ZTF25abjmnps, reported by Stein et al. (GCN 41414) and possibly associated with the candidate gravitational wave signal S250818k (LVK Collaboration, GCN 41437, 41440), with the OSIRIS instrument mounted on the GTC telescope. Our observations began at 2025-08-21 21:40 UTC (3.9 days after the trigger) and were carried out in the r and z filters with an average airmass of ~1.3 and excellent seeing. After image subtraction against Legacy Survey templates (Dey et al. 2019), we detect the source with a preliminary magnitude of r~23.4 AB, consistent with the near-contemporaneous observations of Malesani et al. (GCN 41492). We also confirm a very red color, in agreement with earlier observations (Hall et al., GCN 41433; O’Connor et al., GCN 41452; Gillanders et al., GCN 41454; Liu et al., GCN 41461; Perley et al., GCN 41480). Further observations are planned. We thank the staff at the GTC, especially Antonio García Rodríguez, Antonio Marante Barreto, and Antonio Cabrera for the rapid execution of these observations. View this GCN Circular online at https://gcn.nasa.gov/circulars/41502. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39565] LIGO/Virgo/Kagra S250818k: STEP/T80N upper limits on 2025ulz
by GCN Circulars 22 Aug '25

22 Aug '25

TITLE: GCN CIRCULAR NUMBER: 41501 SUBJECT: LIGO/Virgo/Kagra S250818k: STEP/T80N upper limits on 2025ulz DATE: 25/08/22 17:12:58 GMT FROM: André Santos at Centro Brasileiro de Pesquisas Físicas (CBPF) <andsouzasanttos(a)gmail.com> A. Santos (CBPF), C. R. Bom (CBPF), C. D. Kilpatrick (Northwestern), L. Santana-Silva (CBPF), P. Darc (CBPF), Gabriel Teixeira (CBPF), C. Mendes de Oliveira (IAG-USP) report on behalf of the STEP collaboration We observed the optical transient AT2025ulz (Stein et al., GCN 41414; Busmann et al., GCN 41421; Hall et al., GCN 41433; Karambelkar et al., GCN 41436; O’Connor et al., GCN 41452; Gillanders et al., GCN 41454; Liu et al., GCN 41461; Banerjee et al., GCN 41476; Perley et al., GCN 41480; P. D'Avanzo et al., GCN 41489; Malesani et al., GCN 41492; Smartt et al., GCN 41493), possibly associated with the GW superevent S250818k (LVK Collaboration, GCN 41437, GCN 41440), using the T80N 0.8-m robotic telescope using the 1.4 x 1.4 FoV T80N-Cam imager. The observations started on Aug 21, 21:46 UT (~3.85 days after trigger). We obtained 600s (2x300s)and 1200s (4x300s) stacked exposures in r and i bands respectively, with the T80-Cam centered at the position of the reported transient. Subtracting Pan-SSTARRS templates available at MAST archive using photpipe (Rest et al. 2005), we do not detect any sources in our difference images and derive 3-sigma limiting magnitudes of r > 22.9 and i > 22.8 mag for the transient. We thank the OAJ Data Processing and Archiving Department (DPAD) for reducing and calibrating the OAJ data used in this work, as well as the distribution of the data products through a dedicated web portal. View this GCN Circular online at https://gcn.nasa.gov/circulars/41501. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39564] LIGO/Virgo/KAGRA S250818k: 3 GHz MeerKAT observations of AT2025ulz
by GCN Circulars 22 Aug '25

22 Aug '25

TITLE: GCN CIRCULAR NUMBER: 41500 SUBJECT: LIGO/Virgo/KAGRA S250818k: 3 GHz MeerKAT observations of AT2025ulz DATE: 25/08/22 16:13:06 GMT FROM: Aishwarya L Thakur at INAF-IAPS, Rome <aishth(a)outlook.com> G. Bruni [1], L. Piro [1], G. Gianfagna [1] and A. L. Thakur [1] report: We observed the field of AT2025ulz (announced by Stein et al., GCN 41414), which is proposed as a candidate counterpart for the subthreshold GW event S250818k (LVK Collaboration, GCNs 41437, 41440) with the MeerKAT radio telescope under the program SCI-20241101-GB-01 (PI: Bruni) at 3 GHz (S4 band) starting on Aug 21, 16:30 UT (at 3.6 days post-trigger) for a total of 2 hours (1.5 hours on source). J1939-6342 was used for flux scale calibration, and J1609+2641 for phase referencing. Data was processed with the SARAO Science Data Processor (SDP) continuum pipeline. The image RMS was 6.4 uJy/beam. We detect radio emission at the position of the transient, and we measure an integrated flux density of 77 +/- 16 uJy (corresponding to a ~ 10-sigma detection). However, given the northern declination of the field, the angular resolution is insufficient to disentangle any potential contamination from the host with this epoch of observation alone. Further MeerKAT observations are planned. The MeerKAT telescope is operated by the South African Radio Astronomy Observatory, which is a facility of the National Research Foundation, an agency of the Department of Science and Innovation. —------------------------ [1] INAF-IAPS View this GCN Circular online at https://gcn.nasa.gov/circulars/41500. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39563] GRB 250806A: Gemini observations of host galaxy candidate
by GCN Circulars 22 Aug '25

22 Aug '25

TITLE: GCN CIRCULAR NUMBER: 41499 SUBJECT: GRB 250806A: Gemini observations of host galaxy candidate DATE: 25/08/22 16:12:48 GMT FROM: gsriniv2(a)umd.edu C. Sevilla (Cornell), G. Srinivasaragavan (UMD), D. A. Perley (LJMU), A. Y. Q. Ho (Cornell), A. Bochenek (LJMU) report: We observed the candidate host galaxy of GRB 250806A (Xie et al., GCN 41243, Malesani et al. GCN 41279) beginning UTC 2025-08-13 13:14:40 with the Gemini Multi-Object Spectrograph on Gemini North under program GN-2025B-Q-125 (PI: Srinivasaragavan). We use a 1 arcsecond slit, the R400 grating, and the GG455 filter. We obtained four exposures of 450 seconds each, two at a central wavelength of 520 nm and two at 525 nm. We obtain a redshift of 0.367 from galactic Hβ, [O II], and [O III] emission lines. At this redshift, using the 4 - 120 keV flux from Bouchet et al. (GCN 41287) and observed burst time of 20 seconds, we estimate the burst has an isotropic equivalent energy of ~ 8e49 erg. We thank the Gemini Contact Scientists and the Gemini Helpdesk for their assistance in observing and data reduction. View this GCN Circular online at https://gcn.nasa.gov/circulars/41499. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39562] IPN triangulation of GRB 250821B (long/bright)
by GCN Circulars 22 Aug '25

22 Aug '25

TITLE: GCN CIRCULAR NUMBER: 41498 SUBJECT: IPN triangulation of GRB 250821B (long/bright) DATE: 25/08/22 15:46:04 GMT FROM: Dmitry Svinkin at Ioffe Institute <svinkin(a)mail.ioffe.ru> A.S. Kozyrev, D.V. Golovin, M.L. Litvak, I.G. Mitrofanov, and A.B. Sanin on behalf of the HEND/Mars Odyssey team, D. Svinkin, D. Frederiks, A. Lysenko, A. Ridnaia, and T. Cline on behalf of the Konus-Wind team, A. Goldstein, M. S. Briggs, C. Wilson-Hodge, and E. Burns on behalf of the Fermi GBM team, and W. Boynton, C. Fellows, K. Harshman, H. Enos, R. Starr, and A.S. Gardner on on behalf of the GRS-Odyssey GRB team, report: The bright, long-duration GRB 250821B (Ferm-GBM detection: The Fermi GBM team, GCN 41473; Smith and Meegan, GCN 41477; BALROG localization: Preis and Greiner, GCN 41475; SVOM-GRM detection: Tan et al., GCN 41486) was detected by Fermi (GBM trigger 777485272), SVOM (GRM), Konus-Wind, and Mars-Odyssey (HEND), at about 58067 s UT (16:07:47). We have triangulated it to a preliminary, 3 sigma error box whose coordinates are: --------------------------------------------- RA(2000), deg Dec(2000), deg --------------------------------------------- Center: 29.373 (01h 57m 30s) -82.081 (-82d 04' 51") Corners: 26.171 (01h 44m 41s) -82.255 (-82d 15' 19") 32.420 (02h 09m 41s) -81.925 (-81d 55' 30") 32.427 (02h 09m 42s) -81.883 (-81d 52' 58") 26.212 (01h 44m 51s) -82.213 (-82d 12' 48") --------------------------------------------- The error box area is 127 sq. arcmin, and its maximum dimension is 56 arcmin (the minimum one is 2 arcmin). The Sun distance was 106 deg. This localization may be improved. The IPN localization is consistent with, but reduces the area of, the Fermi-GBM (GCN 41473) and BALROG (GCN 41475) localizations. A triangulation map and HEALPix FITS file are posted at http://www.ioffe.ru/LEA/GRBs/GRB250821_T58069/IPN The HEALPix triangulation map is the multi-order HEALPix in units of probability density. The Konus-Wind time history and spectrum will be given in a forthcoming GCN Circular. View this GCN Circular online at https://gcn.nasa.gov/circulars/41498. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39561] GRB 250821A: Kilonova-Catcher optical upper limits
by GCN Circulars 22 Aug '25

22 Aug '25

TITLE: GCN CIRCULAR NUMBER: 41497 SUBJECT: GRB 250821A: Kilonova-Catcher optical upper limits DATE: 25/08/22 15:19:10 GMT FROM: Damien Turpin at CEA-Saclay <dturpin-astro(a)hotmail.com> M. Freeberg (KNC), D. Turpin (CEA-Saclay/Irfu), C. Andrade(UMN), M. Pillas (ULiege), S. Antier (OCA/IJCLAB) on behalf of the GRANDMA/Kilonova-Catcher collaboration: We observed the field of GRB 250821A detected by Swift/BAT (Dichiara et al., GCN 41462) with the GRANDMA citizen science project Kilonova-catcher (KNC). Our observations were performed with the iTelescope T32 telescope located at Siding Spring Observatory and operated by M. Freeberg. Our observations started at T0+17 min. In our stacked frames, subtracted from the PanSTARRS DR2 template image, we do not detect any optical counterpart inside the Swift/XRT enhanced position (Beardmore et al., GCN 41472). We report our follow-up results in the table below: +---------------+-----------+-----------+----------------------+-------------+ | Tmid-TGRB (hr)| Exp (s) | Filter | Magnitude | Instrument | +===============+===========+===========+======================+=============+ | 0.86 | 20 x 180s | Ic (Vega) | 19.4 (U.L., 5 sigma) | T32 | +---------------+-----------+-----------+----------------------+-------------+ All the data have been reduced by a single data processing pipeline, STDPipe (Karpov et al., 2022). Images obtained in Johnson Cousin filters were calibrated using the Gaia DR3 Synphot catalog. We use the SkyPortal application (skyportal.io) to monitor our observational campaign (Coughlin et al. 2023). GRANDMA is a worldwide telescope network (grandma.ijclab.in2p3.fr) devoted to the observation of transients in the context of multi-messenger astrophysics (Antier et al. 2020 MNRAS 497, 5518). Kilonova-Catcher (KNC) is the citizen science program of GRANDMA (http://kilonovacatcher.in2p3.fr/) View this GCN Circular online at https://gcn.nasa.gov/circulars/41497. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39560] EP250821a: Swift/XRT counterpart fading
by GCN Circulars 22 Aug '25

22 Aug '25

TITLE: GCN CIRCULAR NUMBER: 41496 SUBJECT: EP250821a: Swift/XRT counterpart fading DATE: 25/08/22 14:41:37 GMT FROM: Simone Dichiara at Pennsylvania State University <sbd5667(a)psu.edu> S. Dichiara (PSU), S. R. Oates (Lancaster U.), J.A. Kennea (PSU), K.L. Page (U. Leicester) report on behalf of the Swift-XRT and Swift-UVOT team: Swift-XRT has performed further follow-up observations of the EP-WXT transient EP250821a (Hu et al., GCN 41459), collecting a total of 3.0 ks of Photon Counting (PC) mode data between T0+61.0 ks and T0+72.9 ks. The source detected in XRT in the first 1.9 ks of data previously reported as “Source 1” (Dichiara et al., GCN 41469), consistent with the optical counterpart (Li et al., GCN 41470, Yao et al., GCN 41485, An et al., GCN 41490), has faded more than 3 sigma in the latest X-ray observation. The count rate derived from the follow-up observation is 2.2 (+/-0.3) x 10^-2 cts/s. The light curve can be modelled with a power-law decay with an index of alpha=1.03 +/- 0.07. A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 2.0 +/- 0.2. The best-fitting absorption column is 1.4 (+0.7, -0.6) x 10^21 cm^-2 , in excess of the Galactic value of 7.26 x 10^20 cm^-2 (Willingale et al. 2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.51 x 10^-11 (4.48 x 10^-11) erg cm^-2 count^-1. The observed (unabsorbed) flux obtained from the follow-up observations from T0+61.0 ks to T0+72.9 ks is thus 7.7 x 10^-13 (9.9 x 10^-12) erg cm^-2 s^-1. The results of the XRT-team automatic analysis are available at https://www.swift.ac.uk/EP/EP_FIELD00059/ This circular is an official product of the Swift-XRT team. View this GCN Circular online at https://gcn.nasa.gov/circulars/41496. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39559] GRB 250812A: SVOM/ECLAIRs refined analysis
by GCN Circulars 22 Aug '25

22 Aug '25

TITLE: GCN CIRCULAR NUMBER: 41495 SUBJECT: GRB 250812A: SVOM/ECLAIRs refined analysis DATE: 25/08/22 14:39:39 GMT FROM: SVOM_group <svomgroup(a)bao.ac.cn> L. Bouchet, J.-L. Atteia , O. Godet, M. Brunet (IRAP), L. P. Xin(NAOC), Z.M. Wang(BNU) report on behalf of the SVOM/ECLAIRs team: Using the ECLAIRs event-by-event data downloaded through the X-band ground station, we report further analysis of ECLAIRs observations of GRB 250812A (SVOM burst-id sb25081201), triggered by ECLAIRs onboard SVOM (Xin et al., GCN 41322). The burst is faint and the 4-120 keV lightcurve is featureless. The time-averaged spectrum from T0-51 s to T0+3 s (T0 = 2025-08-12T02:46:03 UTC) in the energy range 4-120 keV is relatively well fitted by a powerlaw model with index -1.19+/-0.27. With this model, the fluence in 4-120 keV is about 7.5 (-1.9,+0.6) e-7 erg/cm^2. All quoted errors are at the 68% confidence level. The spectral index suggests that the Epeak value is above 120 keV. The source redshift is found to be z=2.571 (Van Dalen et al., GCN 41347; de Ugarte Postigo et al., GCN 41348). At this redshift, GRB 250812A lies in the region of type II GRBs in the Amati plot for values of Epeak ≤ 200 keV. We note that the calibration of SVOM/ECLAIRs is ongoing thus these results are preliminary. The Space-based multi-band astronomical Variable Objects Monitor (SVOM) is a China-France joint mission led by the Chinese National Space Administration (CNSA), French Space Agency (CNES), and the Chinese Academy of Sciences (CAS), which is dedicated to observing gamma-ray bursts and other transient phenomena in the energetic universe. ECLAIRs was developed jointly by CNES, CEA-IRFU, CNRS-IRAP, CNRS-APC. The SVOM/ECLAIRs point of contact for this GCN circular is: Laurent Bouchet (laurent.bouchet(a)irap.omp.eu) View this GCN Circular online at https://gcn.nasa.gov/circulars/41495. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39558] GRB 250821A: Swift-BAT refined analysis
by GCN Circulars 22 Aug '25

22 Aug '25

TITLE: GCN CIRCULAR NUMBER: 41494 SUBJECT: GRB 250821A: Swift-BAT refined analysis DATE: 25/08/22 14:31:30 GMT FROM: Rahul Gupta at NASA GSFC <rahul.gupta(a)nasa.gov> A. Y. Lien (U Tampa), S. D. Barthelmy (GSFC), S. Dichiara (PSU), R. Gupta (GSFC), H. A. Krimm (NSF), S. Laha (GSFC/UMBC), C. B. Markwardt (GSFC), M. J. Moss (GSFC), D. M. Palmer (LANL), T. Parsotan (GSFC), D. Sadaula (GSFC/UMBC), T. Sakamoto (AGU) (i.e. the Swift-BAT team): Using the data set from T-240 to T+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 250821A (trigger #1344131) (Dichiara, et al., GCN Circ. 41462). The BAT ground-calculated position is RA, Dec = 358.427, -28.631 deg which is RA(J2000) = 23h 53m 42.6s Dec(J2000) = -28d 37' 53.3" with an uncertainty of 2.1 arcmin, (radius, sys+stat, 90% containment). The partial coding was 64%. The mask-weighted BAT light curve exhibits a short-duration main emission starting from ~T-0.5 to ~T+1.2 sec, followed by a weaker, extended emission which last up to ~ T+18 sec. T90 (15-350 keV) is 1.52 +- 0.37 sec (estimated error including systematics). The time-averaged spectrum from T-0.46 to T+1.20 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 0.83 +- 0.41. The fluence in the 15-150 keV band is 1.3 +- 0.3 x 10^-07 erg/cm2. The 1-sec peak photon flux measured from T+0.06 sec in the 15-150 keV band is 0.9 +- 0.2 ph/cm2/sec. All the quoted errors are at the 90% confidence level. The results of the batgrbproduct analysis are available at https://swift.gsfc.nasa.gov/results/batgrbcat/BAT_refined_circular/1344131 View this GCN Circular online at https://gcn.nasa.gov/circulars/41494. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39557] LIGO/Virgo/KAGRA S250818k: Pan-STARRS coverage of the skymap and candidate counterparts
by GCN Circulars 22 Aug '25

22 Aug '25

TITLE: GCN CIRCULAR NUMBER: 41493 SUBJECT: LIGO/Virgo/KAGRA S250818k: Pan-STARRS coverage of the skymap and candidate counterparts DATE: 25/08/22 14:09:35 GMT FROM: James Gillanders at University of Oxford <jhgillanders.astro(a)gmail.com> S. J. Smartt, J. H. Gillanders (Oxford), M. E. Huber, K. C. Chambers (IfA, Univ. Hawaii), K. W. Smith (Oxford/QUB), S. Srivastav, F. Stoppa, H. Stevance, J. Tweddle (Oxford), M. Nicholl, D. R. Young, A. Aamer, C. R. Angus, M. D. Fulton, D. Magill, M. McCollum, T. Moore, S. Sim, J. Weston, X. Sheng (QUB), T.-W. Chen (NCU, Taiwan), L. Shingles (GSI/QUB), P. Ramsden (Birmingham/QUB), A. S. B. Schultz, T. de Boer, J. Fairlamb, C. C. Lin, T. Lowe, E. Magnier, P. Minguez, G. Paek, I. A. Smith, R. J. Wainscoat (IfA, Univ. Hawaii), A. Rest (STScI), C. Stubbs (Harvard). We surveyed the skymap of the gravitational wave event S250818k (LVK Collaboration, GCNs 41437, 41440) using the Pan-STARRS twin telescope system (Chambers et al., 2016, arXiv e-prints, 1612.05560). Following on from the reported optical candidate AT2025ulz (Stein et al., GCN 41414; Busmann et al., GCN 41421; Hall et al., GCN 41433; Karambelkar et al., GCN 41436; O’Connor et al., GCN 41452; Gillanders et al., GCN 41454; Liu et al., GCN 41461; Perley et al., GCN 41480, D’Avanzo et al. GCN 41489), we have been taking targeted grizy imaging of this transient (Gillanders et al., GCN 41454). At this specific region we have proprietary data to make significantly deeper reference stacks than those that are available through the STScI public website, and monitoring with Pan-STARRS is ongoing. For the rest of the northern portion of the GW skymap, we surveyed the region in the i-band over three nights: 2025 Aug 20, 21, 22. We covered ~288 square degrees and ~33% of the bilby.fits skymap 90% area each night, with multiple 45s (Aug 20) and 120s (Aug 21, 22) exposures. The images were processed with the Pan-STARRS pipeline. After astrometric and photometric calibration, reference images were subtracted from the target stacked images (Magnier et al., 2020a, ApJS, 251, 3; Magnier et al., 2020b, ApJS, 251, 6; Waters et al., 2020, ApJS, 251, 4). Transient candidates were identified and run through our standard filtering procedures, including rejection of artefacts with machine learning tools and cross-matching with galaxy, stellar and solar-system catalogs (e.g., Smith et al., 2020, PASP, 132, 1; Smartt et al., 2024, MNRAS 528, 2299). The depth of our images are typically i ~ 21 - 21.5 per exposure, with the first night having better seeing and transparency conditions. We detected 68 candidate extragalactic transients, of which 30 were already registered on the IAU Transient Name Server (TNS) as having been discovered and detected before S250818k merger time. We have registered the other 38 sources on the TNS. To down-select for optical counterpart candidates of S250818k, we applied the following filters: 1. Spatially associated with a host galaxy that has a photometric or spectroscopic redshift within the 2-sigma limit from LVK of 0.025 < z < 0.08, 2. Has some indication of lightcurve evolution over the three nights of observation, 3. We rejected all faint transients spatially coincident with the nucleus of galaxies as being due to either AGN variability or possible subtraction artefacts. We found no plausible candidate for the optical counterpart of S250818k other than AT2025ulz. Six sources with plausible kilonova-like absolute magnitudes and in hosts with consistent redshifts (within errors) with S250818k were found (AT2025uuw, AT2025uso, AT2025uuf, AT2025utr, AT205usy, AT2025uxs), but their lightcurves are either rising or are flat and show no evolution over 48hrs, and they do not appear to be viable candidates at this point. Discovery details and magnitudes of the ATs can be found on the TNS. Operation of the Pan-STARRS1 and Pan-STARRS2 telescopes is primarily supported by the National Aeronautics and Space Administration under Grant No. NNX12AR65G and NNX14AM74G, issued through the SSO Near-Earth Object Observations Program. Data processing is enabled by Queen's University Belfast and the University of Oxford, enabled through STFC grants ST/Y001605/1, ST/T000198/1 and ST/X001253/1, the Royal Society, and the Hintze Centre for Astrophysical Surveys. View this GCN Circular online at https://gcn.nasa.gov/circulars/41493. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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