https://www.astronomerstelegram.org Star, from The Astronomer's Telegram en-us https://www.astronomerstelegram.org/?read=17818 Alessio Marino, Francesco Coti Zelati, Nanda Rea, Yilong Wang, Giulia Illiano, Minghao Zhang, Chen Wang, Biao Zhang, Jiapei Feng, Haiwu Pan Alessio Marino, Francesco Coti Zelati, Nanda Rea, Yilong Wang, Giulia Illiano, Minghao Zhang, Chen Wang, Biao Zhang, Jiapei Feng, Haiwu Pan marino@ice.csic.es Credentialed by: Alessio Marino (marino@ice.csic.es) The Astronomer's Telegram ATel17818 We report on the detection of a new outburst from the neutron star low-mass X-ray binary MXB 1730-335 (a.k.a. the Rapid Burster) with the Wide-field X-ray Telescope (WXT) onboard Einstein Probe (EP). ... 2026-05-27T15:18:27-00:00 https://www.astronomerstelegram.org/?read=17816 M. Nakajima, T. Mihara, H. Negoro, 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, H. Sugai, N. Nagashima, Y. Ishihara, M. Shidatsu, C. Kang, T. Nakamoto, M. Uenishi, T. Usuki, S. Yatsuzuka, 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, T. Mihara, H. Negoro, 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, H. Sugai, N. Nagashima, Y. Ishihara, M. Shidatsu, C. Kang, T. Nakamoto, M. Uenishi, T. Usuki, S. Yatsuzuka, 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 ATel17816 The MAXI/GSC nova alert system triggered on a weak X-ray brightening from the Be/X-ray binary pulsar LS V +44 17 (RX J0440.9+4431) on 2026 May 22 (MJD 61182). ... 2026-05-27T02:00:01-00:00 https://www.astronomerstelegram.org/?read=17815 M. Nakajima, T. Mihara, M. Sugizaki, H. Negoro, 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, H. Sugai, N. Nagashima, Y. Ishihara, M. Shidatsu, C. Kang, T. Nakamoto, M. Uenishi, T. Usuki, S. Yatsuzuka, 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, W. Iwakiri, T. Kawamuro, S. Yamada, S. Ogawa M. Nakajima, T. Mihara, M. Sugizaki, H. Negoro, 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, H. Sugai, N. Nagashima, Y. Ishihara, M. Shidatsu, C. Kang, T. Nakamoto, M. Uenishi, T. Usuki, S. Yatsuzuka, 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, 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 ATel17815 The MAXI/GSC nova alert system triggered on an X-ray brightening from the Be/X-ray binary pulsar 1A 0535-66 (also known as 1A 0538-66) on 2026 May 21 (MJD 61181; see the MAXI alert page at https://maxi.riken.jp/alert/novae/1181387701/1181387701.htm ). ... 2026-05-26T14:00:05-00:00 https://www.astronomerstelegram.org/?read=17794 A. Miyamoto, K. Fukushima, Y. Kanemaru, A. Miyamoto, Y. Omiya, Y. Uchida, T. Yoneyama, M. Audard, E. Behar, T. Hakamata, S. Inoue, Y. Ishihara, C. Kang, T. Kiyomoto, T. Kohmura, H. Kuramoto, Y. Maeda, H. Matsumoto, M. Mizumoto, Y. Motogami, T. Narita, M. Nobukawa, H. Noda, S. Ogawa, Y. Sakamoto, M. Shidatsu, H. Takahashi, T. Takagi, S. Takatsuka, F. Takisawa, Y. Terada, Y. Terashima, Y. Tsuboi, H. Uchida, A. Yoshimoto, M. Yoshimoto A. Miyamoto, K. Fukushima, Y. Kanemaru, A. Miyamoto, Y. Omiya, Y. Uchida, T. Yoneyama, M. Audard, E. Behar, T. Hakamata, S. Inoue, Y. Ishihara, C. Kang, T. Kiyomoto, T. Kohmura, H. Kuramoto, Y. Maeda, H. Matsumoto, M. Mizumoto, Y. Motogami, T. Narita, M. Nobukawa, H. Noda, S. Ogawa, Y. Sakamoto, M. Shidatsu, H. Takahashi, T. Takagi, S. Takatsuka, F. Takisawa, Y. Terada, Y. Terashima, Y. Tsuboi, H. Uchida, A. Yoshimoto, M. Yoshimoto kxfukushima@gmail.com Credentialed by: Kotaro Fukushima (kxfukushima@gmail.com) The Astronomer's Telegram ATel17794 XRISM/Xtend Transient Search (XTS) identified an additional X-ray transient from the source XRISM J0602-4006, potentially corresponding to 2CXO J060212.4-400619 (ATel #17785), on 2026-05-10 TT. ... 2026-05-11T14:03:11-00:00 https://www.astronomerstelegram.org/?read=17785 M. Yoshimoto, Y. Terada, Y. Kanemaru, A. Miyamoto, Y. Omiya, Y. Uchida, T. Yoneyama, M. Audard, E. Behar, K. Fukushima, T. Hakamata, S. Inoue, Y. Ishihara, C. Kang, T. Kiyomoto, T. Kohmura, H. Kuramoto, Y. Maeda, H. Matsumoto, A. Miyamoto, M. Mizumoto, Y. Motogami, T. Narita, M. Nobukawa, H. Noda, S. Ogawa, Y. Sakamoto, M. Shidatsu, H. Takahashi, T. Takagi, S. Takatsuka, F. Takisawa, Y. Terashima, Y. Tsuboi, H. Uchida, A. Yoshimoto M. Yoshimoto, Y. Terada, Y. Kanemaru, A. Miyamoto, Y. Omiya, Y. Uchida, T. Yoneyama, M. Audard, E. Behar, K. Fukushima, T. Hakamata, S. Inoue, Y. Ishihara, C. Kang, T. Kiyomoto, T. Kohmura, H. Kuramoto, Y. Maeda, H. Matsumoto, A. Miyamoto, M. Mizumoto, Y. Motogami, T. Narita, M. Nobukawa, H. Noda, S. Ogawa, Y. Sakamoto, M. Shidatsu, H. Takahashi, T. Takagi, S. Takatsuka, F. Takisawa, Y. Terashima, Y. Tsuboi, H. Uchida, A. Yoshimoto yoshimoto.marina.gr@ehime-u.ac.jp Credentialed by: Yukikatsu Terada (terada@mail.saitama-u.ac.jp) The Astronomer's Telegram ATel17785 XRISM/Xtend Transient Search (XTS) detected an X-ray flare from an X-ray source XRISM J0602-4006 on 2026-05-08 TT. The source position is determined to be (R.A., Dec.) = (90.551, -40.105), with a systematic error of & sim; 40 arcsec. ... 2026-05-09T14:45:27-00:00 https://www.astronomerstelegram.org/?read=17784 Marchev, D. ; Borisov, B. ; Atanasova-Sartliiska, T. ; Yordanova, G. ; Georgiev, A. ; Marchev, V. Marchev, D. ; Borisov, B. ; Atanasova-Sartliiska, T. ; Yordanova, G. ; Georgiev, A. ; Marchev, V. vlad.marchev@gmail.com Credentialed by: Vladislav Marchev (vlad.marchev@gmail.com) The Astronomer's Telegram ATel17784 We present our recent photometric observations of T CrB obtained on the 5th and 6th of May 2026 and we compare them with the ones from ATel#17052 an year ago. ... 2026-05-09T14:36:32-00:00 https://www.astronomerstelegram.org/?read=17779 S. Takatsuka, M. Mizumoto, Y. Kanemaru, Y. Omiya, Y. Uchida, T. Yoneyama, M. Audard, E. Behar, K. Fukushima, T. Hakamata, S. Inoue, Y. Ishihara, C. Kang, T. Kiyomoto, T. Kohmura, H. Kuramoto, J. Kurashima, Y. Maeda, H. Matsumoto, A. Miyamoto, K. Mori, Y. Motogami, T. Narita, M. Nobukawa, H. Noda, S. Ogawa, Y. Sakamoto, M. Shidatsu, H. Takahashi, T. Takagi, F. Takisawa, Y. Terada, Y. Terashima, Y. Tsuboi, H. Uchida, A. Yoshimoto, M. Yoshimoto S. Takatsuka, M. Mizumoto, Y. Kanemaru, Y. Omiya, Y. Uchida, T. Yoneyama, M. Audard, E. Behar, K. Fukushima, T. Hakamata, S. Inoue, Y. Ishihara, C. Kang, T. Kiyomoto, T. Kohmura, H. Kuramoto, J. Kurashima, Y. Maeda, H. Matsumoto, A. Miyamoto, K. Mori, Y. Motogami, T. Narita, M. Nobukawa, H. Noda, S. Ogawa, Y. Sakamoto, M. Shidatsu, H. Takahashi, T. Takagi, F. Takisawa, Y. Terada, Y. Terashima, Y. Tsuboi, H. Uchida, A. Yoshimoto, M. Yoshimoto yoneyama.tomokage@jaxa.jp Credentialed by: Tomokage Yoneyama (tyoneyama263@g.chuo-u.ac.jp) The Astronomer's Telegram ATel17779 XRISM/Xtend Transient Search (XTS) detected an X-ray flare from an X-ray source XRISM J2052-5701 on 2026-05-02 TT. The source position is determined to be (R.A., Dec.) = (313.049, -57.017) with a systematic error of & sim; 40 arcsec. ... 2026-05-08T06:43:47-00:00 https://www.astronomerstelegram.org/?read=17772 H. Negoro, M. Nakajima, H. Aoe, K. Saito, T. Yokoyama, M. Wada, T. Mihara, 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, 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, and S. Ogawa H. Negoro, M. Nakajima, H. Aoe, K. Saito, T. Yokoyama, M. Wada, T. Mihara, 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, 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, and S. Ogawa negoro.hitoshi@nihon-u.ac.jp Credentialed by: Hitoshi Negoro (negoro@phys.cst.nihon-u.ac.jp) The Astronomer's Telegram ATel17772 The MAXI/GSC nova alert system triggered on a bright X-ray transient source at 08:47:31 UT on April 30, 2026. Assuming that the source flux was constant over the transit, we obtain the source position using the GSC_2 counter at (R.A., Dec) = (129.480 deg, -43.152 deg) = (08 37 55, -43 09 07) (J2000) with a statistical 90% C.L. ... 2026-05-01T15:12:22-00:00 https://www.astronomerstelegram.org/?read=17770 F. Cangemi, A. Coleiro, M. Dennefeld, O. Godet, D. Götz, S. Guillot, S. Le Stum, H.-L. Li, S. Schanne, L. Tao, L.-P. Xin, L. Zhang F. Cangemi, A. Coleiro, M. Dennefeld, O. Godet, D. Götz, S. Guillot, S. Le Stum, H.-L. Li, S. Schanne, L. Tao, L.-P. Xin, L. Zhang cangemi@apc.in2p3.fr Credentialed by: Floriane Cangemi (cangemi@apc.in2p3.fr) The Astronomer's Telegram ATel17770 On Monday, April 27, 2026, at 13:58:46.114 UT, the onboard trigger software of the SVOM/ECLAIRs telescope detected and localized a source at R.A. = 284.818 deg and Dec. ... 2026-04-30T09:35:08-00:00 https://www.astronomerstelegram.org/?read=17761 J. Kurashima, K. Mori, Y. Kanemaru, Y. Omiya, Y. Uchida, T. Yoneyama, M. Audard, E. Behar, K. Fukushima, T. Hakamata, S. Inoue, Y. Ishihara, C. Kang, T. Kiyomoto, T. Kohmura, H. Kuramoto, Y. Maeda, H. Matsumoto, A. Miyamoto, M. Mizumoto, Y. Motogami, T. Narita, M. Nobukawa, H. Noda, S. Ogawa, Y. Sakamoto, M. Shidatsu, H. Takahashi, T. Takagi, S. Takatsuka, F. Takisawa, Y. Terashima, Y. Tsuboi, H. Uchida, A. Yoshimoto, M. Yoshimoto, Y. Terada J. Kurashima, K. Mori, Y. Kanemaru, Y. Omiya, Y. Uchida, T. Yoneyama, M. Audard, E. Behar, K. Fukushima, T. Hakamata, S. Inoue, Y. Ishihara, C. Kang, T. Kiyomoto, T. Kohmura, H. Kuramoto, Y. Maeda, H. Matsumoto, A. Miyamoto, M. Mizumoto, Y. Motogami, T. Narita, M. Nobukawa, H. Noda, S. Ogawa, Y. Sakamoto, M. Shidatsu, H. Takahashi, T. Takagi, S. Takatsuka, F. Takisawa, Y. Terashima, Y. Tsuboi, H. Uchida, A. Yoshimoto, M. Yoshimoto, Y. Terada yoneyama.tomokage@jaxa.jp Credentialed by: Tomokage Yoneyama (tyoneyama263@g.chuo-u.ac.jp) The Astronomer's Telegram ATel17761 XRISM/Xtend Transient Search (XTS) detected an X-ray flare from an X-ray source XRISM J0534-6855, on 2026-04-17 TT. The source position is determined to be (R.A., Dec.) = (83.396, -68.915) with a systematic error of & sim; 40 arcsec. ... 2026-04-23T13:59:33-00:00