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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 555: Correction to Alert Notice 554 on V420 Aur (HD 34921)

October 4, 2016: In AAVSO Alert Notice 554 the star was inadvertently referred to as V420 Oph in the sections creating charts and reporting observations.

Charts with a comparison star sequence for V420 Aur may be created using the AAVSO Variable Star Plotter (VSP).

Please submit observations to the AAVSO International Database using the name V420 AUR.

Coordinates for V420 Aur (2000.0): R.A. 05 22 35.23  Dec. +37 40 33.6

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 377: Request extended to observe HMXBs in support of radial velocity observations

May 2, 2008: Dr. Gordon Sarty, University of Saskatchewan, Canada, has requested our continuing assistance (see AAVSO Alert Notices 348 and 354) in his ongoing radial velocity observations of four High Mass X-ray Binaries (HMXBs). From Dr. Sarty:

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