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AAVSO Alert Notice

Alert Notice 523: Correction to AAVSO Alert Notice 522

July 1, 2015:  In AAVSO Alert Notice 522 on the upcoming observations of the black hole X-ray binary V404 Cyg by HST, the date of the detection by the Swift satellite was incorrectly given as 2015 June 16.77197 UT (Barthelmy et al., GCN Circular 17929). The correct date is 2015 June 15.77197 UT.

Our sincere apologies for this error!

Alert Notice 522: V404 Cyg HST multiwavelength observations scheduled

Correction: In the text below, the date of the detection by the Swift satellite was incorrectly given as 2015 June 16.77197 UT. The correct date is 2015 June 15.77197 UT.

Our sincere apologies for this error!

July 1, 2015:

Alert Notice 521: Very rare outburst of the symbiotic variable AG Peg

June 23, 2015: The symbiotic variable AG Peg is in outburst, the first one observed since its only known outburst, which occurred in 1860-1870. Currently at visual/V magnitude 7.2 (B=7.8), it is an excellent target for visual, PEP, CCD, and DSLR observers and spectroscopists. The current outburst began after 2015 May 27 UT (T. Markham, Leek, Staffordshire, England, from the BAAVSS online database) and was underway by June 13.90 (A. Kosa-Kiss, Salonta, Romania).

Alert Notice 520: X-ray nova and LMXB V404 Cyg in rare outburst

June 18, 2015: V404 Cyg, an X-ray nova and a low mass X-ray binary (LMXB) with black hole component, is undergoing its first reported X-ray and optical outburst since 1989. Large scale, rapid variations are being reported in wavelengths from X-ray to radio by professional and amateur astronomers worldwide.

Alert Notice 519: Nova Sgr 2015 No. 2 fading as dust production rises

June 15, 2015: Nova Sgr 2015 No. 2 (PNV J18365700-2855420; see AAVSO Alert Notice 512) is undergoing a significant fading visually as its infrared excess increases, indicating that substantial dust production is underway.

Alert Notice 518: Observations of 2MASS J06593158-0405277 needed

April 15, 2015: Dr. Fabienne A. Bastien (Hubble Postdoctoral Fellow, Pennsylvania State University) has requested AAVSO assistance in monitoring the rare FU Ori object 2MASS J06593158-0405277 as part of a campaign to observe this T Tauri star from the optical to the infrared in the coming weeks.  

Alert Notice 517: Monitoring of AM Her urgently requested in support of XMM-Newton and NuSTAR observations

April 2, 2015: Dr. Axel Schwope (Leibniz Institute for Astrophysics Potsdam, Germany) has requested AAVSO observers' assistance in monitoring the magnetic variable AM Her in support of upcoming XMM-Newton plus NuSTAR (Nuclear Spectroscopic Telescope Array) observations.

The XMM-Newton observations are scheduled for 2015 April 06 02:37:02-15:07:02 UT. The NuSTAR observations have not been made final yet but are expected to run longer. A Special Notice will be issued when the NuSTAR schedule is known.

Alert Notice 516: Nova Oph 2015 = PNV J17291350-1846120

April 2, 2015

Event: Nova Oph 2015 = PNV J17291350-1846120

Discovered by: Yukio Sakurai, Ibaraki-ken, Japan

Discovery magnitude: 12.2 unfiltered, using 180-mm f/2.8 lens

Discovery date: 2015 March 29.766 UT

Coordinates:  R.A. 17 29 13.58   Dec. -18 46 11.7  (2000.0)

Alert Notice 515: SN 2015F in NGC 2442 (PSN J07361576-6930230)

March 31, 2015

Event: Supernova in NGC 2442: SN 2015F = PSN J07361576-6930230

Discovered by: Libert A. G. Monard, Calitzdorp, Western Cape, South Africa

Discovery magnitude: 16.8 unfiltered CCD using a 35-cm RCX400 telescope (+SBIG ST8-XME camera)

Discovery date: 2015 March 9.789 UT

Coordinates:  R.A. 07 36 15.76   Dec. -69 30 23.0  (2000.0)
SN 2015F is located 40" west and 84" north of the center of NGC 2442.

Alert Notice 514: RW Aur monitoring requested

March 24, 2015: Dr. Hans Moritz Guenther (Massachusetts Institute of Technology) has requested AAVSO observers' assistance with the classical T Tauri star RW Aur (component A). He writes:
 
"RW Aur A is a classical T Tauri surrounded by an accretion disk. It's a visual binary; the B component is fainter and shows no sign of a disk. The separation is 1.4 arcsec, but the B component is so much fainter (V = 13.6) that it's not a problem if the binary is not resolved.

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