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AAVSO International Database

Alert Notice 538: Observations of V694 Mon (MWC 560) requested for Chandra campaign

February 26, 2016: Dr. Jeno Sokoloski (Columbia University) and Mr. Adrian Lucy (graduate student, Columbia University) have requested AAVSO observations of the jet-driving symbiotic star V694 Mon (MWC 560), which is in outburst, in support of upcoming Chandra observations to investigate the state of the inner accretion disk during this outburst.

The Chandra observations are scheduled (preliminary schedule) for 2016 March 8 (7:17-14:13 UTC) and March 9 (2:20-9:17 UTC).

Alert Notice 537: Observations of a secondary eclipse of b Persei requested

February 26, 2016: Dr. Donald F. Collins (AAVSO member, Swannanoa, NC), Dr. Robert Zavala (US Naval Observatory, Flagstaff Station), and Jason Sanborn (Lowell Observatory) request high time-resolution observations of the bright eclipsing star b Persei (not beta) during an expected secondary eclipse of the third star of the system as it is expected to pass behind the close orbiting stars of the system in the two weeks centered on March 7, 2016. Dr. Collins provides the information below.

Special Notice #413: SU UMa observations needed now

February 23, 2016: Deanne Coppejans (Department of Astrophysics, Radboud University Nijmegen) requests observations of the dwarf nova SU UMa now in order to determine its status. She and colleagues observed it on 20 February 2016 with the Very Large Array (VLA) and need to know whether it is (was) in outburst.

Observations of SU UMa in the AAVSO International Database from around the time of the VLA observations show it to be in quiescence:

Alert Notice 536: SS Cyg monitoring requested for radio campaign

February 8, 2016:  Further to AAVSO Special Notice #412, Dr. James Miller-Jones (International Centre for Radio Astronomy Research, Curtin University, Perth, Western Australia) and colleagues have requested AAVSO assistance in support of their multiwavelength (radio and optical) campaign on the dwarf nova SS Cyg. Close monitoring of SS Cyg and immediate reporting of observations to the AAVSO via WebObs is requested beginning now.

Special Notice #412: SS Cyg monitoring needed for radio campaign

February 4, 2016:  A multiwavelength (radio and optical) observing campaign on SS Cyg is underway, and AAVSO participation is urgently requested. An AAVSO Alert Notice will be issued February 5 with full details.

The purpose of this Special Notice is to alert observers right now to the need to monitor SS Cyg very closely and report your observations to the AAVSO via WebObs at once. It is likely to go into outburst very soon, and immediate reporting of outburst behavior is crucial to the success of the campaign.

Alert Notice 535: R Aqr observing campaign

January 19, 2016: Dr. George Wallerstein (University of Washington) has requested AAVSO coverage of the long period/symbiotic variable R Aquarii beginning immediately in support of high resolution spectroscopic observations planned for 2016 January 19 and 21.

Special Notice #411: RT Cru observations need to be continued

December 15, 2015: Further to AAVSO Alert Notice 503 and AAVSO Special Notice #409, Dr. Margarita Karovska (Harvard-Smithsonian Center for Astrophysics) urgently requests that multicolor and visual AAVSO observations of the symbiotic variable RT Cru continue.

R Aqr

December 1, 2015

The long period variable R Aquarii is an extremely interesting system. Its type is both Mira (M) and symbiotic (ZAND) - R Aqr is a close binary system consisting of a hot star and a late-type star, both enveloped in nebulosity. In the case of R Aqr, the late-type star is a Mira. As a result, the very interesting light curve shows not only the Mira pulsation but also eclipses as the two stars interact.

Alert Notice 534: Nova Sgr 2015 No. 4 = PNV J18225925-1914148

November 3, 2015

Event: Nova Sgr 2015 No. 4 = PNV J18225925-1914148

Independent discovery by:  
 - Shigehisa Fujikawa (Kan'onji, Kagawa, Japan, reported via I. Endoh,
National Astronomical Observatory of Japan, Mitaka, Tokyo)
 - Hideo Nishimura (Kakegawa, Shizuoka-ken, Japan, reported via S.
Nakano (Sumoto, Japan))
 - Minoru Yamamoto (Okazaki, Aichi-ken, Japan, reported via S. Nakano)

Special Notice #409: Chandra observations scheduled for RT Cru

October 30, 2015: Further to AAVSO Alert Notice 503, Dr. Margarita Karovska (Harvard-Smithsonian Center for Astrophysics) informs us that the Chandra observations of the symbiotic variable RT Cru have been scheduled.

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