https://www.astronomerstelegram.org Binary, from The Astronomer's Telegram en-us https://www.astronomerstelegram.org/?read=18097 Daniel Jadlovsky, Thomas Granzer, Michael Weber, Kateryna Kravchenko, Andrea Dupree, Miguel Montarges, Laszlo Molnar Daniel Jadlovsky, Thomas Granzer, Michael Weber, Kateryna Kravchenko, Andrea Dupree, Miguel Montarges, Laszlo Molnar jadlovsky@mail.muni.cz Credentialed by: Daniel Jadlovský (jadlovsky@mail.muni.cz) The Astronomer's Telegram ATel18097 Red supergiant Betelgeuse (Alpha Ori; HD 39801; MI1-2 Iab) underwent a historical Great Dimming event during 2019/2020, reaching a minimum of V ~ 1.6 mag in February 2020 (see ATel #13341, #13365, #13410, #13439, #13512, #13518, #13601, #13901, #13982, #15240, #16001, and #16501), close to the brightness minimum of the long secondary period (LSP). ... 2026-10-08T18:50:15-00:00 https://www.astronomerstelegram.org/?read=18094 Andy Pollock, Paul Crowther Andy Pollock, Paul Crowther a.m.pollock@sheffield.ac.uk Credentialed by: Andrew Pollock (a.m.pollock@sheffield.ac.uk) The Astronomer's Telegram ATel18094 R144 = HD38282 is a very massive binary system of two Wolf-Rayet stars classified WN5/6h and WN6/7h and one of the brightest stars in the LMC. Some years ago, ASAS-SN data were the source of the recognition of its binary period of 74 days and the complicated form of its folded light curve that displays one short and one long eclipse and a maximum close to the periastron of its eccentric orbit. ... 2026-10-08T11:15:19-00:00 https://www.astronomerstelegram.org/?read=18089 Manoj Mandal, Sachindra Naik Manoj Mandal, Sachindra Naik manojmandal@prl.res.in Credentialed by: Manoj Mandal (manojmandal@prl.res.in) The Astronomer's Telegram ATel18089 We report preliminary timing and spectral results from the XPoSat/XSPECT observations of the Be/X-ray binary pulsar LS V +44 17 (RX J0440.9+4431) during its ongoing September 2026 X-ray outburst. ... 2026-10-04T09:02:31-00:00 https://www.astronomerstelegram.org/?read=18087 Thomas M. Gaudin, Jamie A. Kennea, Malcolm J. Coe, Kim L. Page, Itumaleng Monageng, David A. H. Buckley, Phil A. Evans Thomas M. Gaudin, Jamie A. Kennea, Malcolm J. Coe, Kim L. Page, Itumaleng Monageng, David A. H. Buckley, Phil A. Evans tmg6006@psu.edu Credentialed by: Thomas Gaudin (tmg6006@psu.edu) The Astronomer's Telegram ATel18087 An X-ray counterpart to the Small Magellanic Cloud (SMC) nova ASASSN-26dt, also known as AT 2026oyp, has been detected for the first time by an observation of the Swift SMC Survey (S-CUBED). ... 2026-10-03T12:18:25-00:00 https://www.astronomerstelegram.org/?read=18082 I. Mereminskiy, A. Semena, A. Lutovinov, S. Molkov, A. Tkachenko I. Mereminskiy, A. Semena, A. Lutovinov, S. Molkov, A. Tkachenko i.a.mereminskiy@gmail.com Credentialed by: Andrey Semena (san@iki.rssi.ru) The Astronomer's Telegram ATel18082 During the observations of the Galactic Plane on Sept. 28, 2026, the Mikhail Pavlinsky ART-XC telescope onboard the SRG observatory detected a bright X-ray source at the position of RA, Dec = 275.1232, -14.5692 (estimated 90% containment radius of 10''), with the observed X-ray flux in 4-12 keV of (7.9+-0.2)x10^-11 erg cm-2 s-1. ... 2026-09-29T13:22:42-00:00 https://www.astronomerstelegram.org/?read=18080 Hang Gong, Shaoqiang Xi, Caisong Liu, Pei Wang, Lingqi Meng, Chenchen Miao, Jifeng Liu, Zhen Cao Hang Gong, Shaoqiang Xi, Caisong Liu, Pei Wang, Lingqi Meng, Chenchen Miao, Jifeng Liu, Zhen Cao ghang.naoc@gmail.com Credentialed by: Hang Gong (ghang.naoc@gmail.com) The Astronomer's Telegram ATel18080 The pulsar position is derived from snapshot observations using the FAST 19-beam receiver, with the 1.5' positional uncertainty dominated by the beam size as it far exceeds the telescope's absolute pointing uncertainty. ... 2026-09-24T11:53:04-00:00 https://www.astronomerstelegram.org/?read=18076 Hang Gong, Shaoqiang Xi, Caisong Liu, Pei Wang, Lingqi Meng, Chenchen Miao, Jifeng Liu, Zhen Cao Hang Gong, Shaoqiang Xi, Caisong Liu, Pei Wang, Lingqi Meng, Chenchen Miao, Jifeng Liu, Zhen Cao ghang.naoc@gmail.com Credentialed by: Hang Gong (ghang.naoc@gmail.com) The Astronomer's Telegram ATel18076 We report the discovery of a new millisecond pulsar binary using the Five-hundred-meter Aperture Spherical radio Telescope (FAST) & #91;1 & #93;. The system was identified at a beam center of R.A. ... 2026-09-23T13:52:13-00:00 https://www.astronomerstelegram.org/?read=18075 G. K. Jaisawal G. K. Jaisawal gaurava@space.dtu.dk Credentialed by: Gaurava Kumar Jaisawal (gaurava.jaisawal@gmail.com) The Astronomer's Telegram ATel18075 We report on a Swift/XRT observation of GS 0834-430, currently in outburst following the onset of X-ray activity seen by MAXI/GSC on 2026 August 29 (ATel #18031). ... 2026-09-23T13:23:03-00:00 https://www.astronomerstelegram.org/?read=18071 M. Nakajima, H. Negoro, T. Mihara, K. Saito, T. Yokoyama, M. Wada, T. Tamagawa, N. Kawai, M. Matsuoka, T. Sakamoto, M. Serino, S. Sugita, Y. Kawakubo, H. Hiramatsu, A. Yoshida, Y. Tsuboi, Y. Ishihara, H. Ogaki, M. Shidatsu, C. Kang, M. Uenishi, T. Usuki, S. Yatsuzuka, H. Aoe, I. Takahashi, Y. Yatsu, S. Nakahira, S. Ueno, H. Tomida, M. Kurihara, Y. Ueda, K. Fujiwara, S. Kobayashi, M. Yamauchi, M. Nishio, C. Hiraizumi, K. Yamaoka, M. Sugizaki, W. Iwakiri, T. Kawamuro, S. Yamada, S. Ogawa M. Nakajima, H. Negoro, T. Mihara, K. Saito, T. Yokoyama, M. Wada, T. Tamagawa, N. Kawai, M. Matsuoka, T. Sakamoto, M. Serino, S. Sugita, Y. Kawakubo, H. Hiramatsu, A. Yoshida, Y. Tsuboi, Y. Ishihara, H. Ogaki, M. Shidatsu, C. Kang, M. Uenishi, T. Usuki, S. Yatsuzuka, H. Aoe, I. Takahashi, Y. Yatsu, S. Nakahira, S. Ueno, H. Tomida, M. Kurihara, Y. Ueda, K. Fujiwara, S. Kobayashi, M. Yamauchi, M. Nishio, C. Hiraizumi, K. Yamaoka, M. Sugizaki, W. Iwakiri, T. Kawamuro, S. Yamada, S. Ogawa nakajima.motoki@nihon-u.ac.jp Credentialed by: Motoki Nakajima (nakajima.motoki@nihon-u.ac.jp) The Astronomer's Telegram ATel18071 We report on anomalous X-ray activity from the Be/X-ray binary pulsar LS V +44 17 (RX J0440.9+4431). This binary system, hosting a & sim;205 sec X-ray pulsar, had previously been suggested to have an orbital period of & sim;150 days, estimated from the recurrence intervals of a series of X-ray outbursts observed in 2010-2011 (Reig 2011; Tsygankov et al. ... 2026-09-22T13:10:54-00:00 https://www.astronomerstelegram.org/?read=18070 I. Mariani, S. E. Motta, R. P. Fender on behalf of the X-KAT collaboration I. Mariani, S. E. Motta, R. P. Fender on behalf of the X-KAT collaboration CorrespondingAuthor'sEmailAddress Credentialed by: Sara Elisa Motta (sara.motta@physics.ox.ac.uk) The Astronomer's Telegram ATel18070 The black hole transient 4U 1630-47 started a new outburst on September 2nd, 2026, as observed by SVOM/ECLAIRs (ATel #18030). Follow-up X-ray observations were carried out with NuSTAR starting on Sep 6th, 2026 (ATel #18034), which showed the rise to hard-intermediate state. ... 2026-09-22T12:38:58-00:00