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Alert Notice 610: Anticipated primary eclipse of b Persei by the third star

January 26, 2018: An AAVSO campaign on the bright star b Per has been launched at the request of Dr. Donald F. Collins, who writes:

Alert Notice 589: R Aqr coverage needed for HST and Chandra observations

Note: This campaign has been extended through the 2018 observing season.

August 4, 2017: Dr. Margarita Karovska (Harvard-Smithsonian Center for Astrophysics) has requested "visual, photometric, and spectroscopic observations of the symbiotic variable R Aqr in preparation for and in support of Chandra and HST observations currently scheduled for October 2017."

Special Notice #429: V694 Mon (MWC 560) spectroscopy requested

May 2, 2017: Further to AAVSO Alert Notice 538, the campaign from 2016 on V694 Mon (MWC 560) has been continued, but with different requirements. Photometry is no longer specifically requested on a regular basis (although ongoing observations that do not interfere with other obligations are welcome). Spectroscopy on a cadence of a week or two is requested to monitor changes in the disk outflow. V694 Mon is presently nearing opposition, but the request for spectroscopy continues until further notice.

Alert Notice 559: Observations of CI Cam needed to support spectroscopy

October 19, 2016: Kelly Gourdji and Marcella Wijngaarden (graduate students at the University of Amsterdam/Anton Pannekoek Institute for Astronomy) have requested AAVSO observers' assistance in providing optical photometry of CI Cam in support of their high-resolution spectroscopy with the Mercator telescope + Hermes spectrograph in La Palma from now through January 2017.

Alert Notice 554: Observations of V420 Aur (HD 34921) needed to support spectroscopy

Note added October 4, 2016: In the original version of this Alert Notice, V420 Aur was referred to as V420 Oph in the sections on creating charts and reporting observations. Also, the range was given as V=7.15-7.35  when the correct value is V=7.35-7.51. The text below has been corrected. Apologies to the PI's for the error.

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

February 26, 2016: Dr. Jeno Sokoloski (Columbia University) and Mx. 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 535: R Aqr observing campaign

Ongoing visual, photometric, and spectroscopic observations of R Aqr about once every 10 days are requested, both to detect and observe the next eclipse and to continue the light curve of this star that has been in the AAVSO observing program for over a century.   Elizabeth O. Waagen, August 2017

Alert Notice 533: Coverage of V5668 Sgr (Nova Sgr 2015 No. 2) requested in support of HST spectroscopy

October 30, 2015: Dr. Peter Kuin (Mullard Space Science Laboratory, University College London) and colleagues in the Swift Nova group have requested AAVSO observers' assistance in multicolor monitoring of V5668 Sgr (Nova Sgr 2015 No. 2, see AAVSO Alert Notices 512, 519) in support of an upcoming spectroscopic observation with the Hubble Space Telescope Imaging Spectrograph (STIS).


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