August 9, 2016
V1687 Cyg spectroscopy and sequence
Further to AAVSO Alert Notice 546, spectroscopy of V1687 Cyg (WR 140, HD 193793) is encouraged. A group of amateur spectroscopists in Germany will be taking spectra in accordance with the parameters given by the astronomers, namely a resolving power >~5000, S/N~100, ideally concentrating on the wavelength region 5500-6000A. A background document sent to these spectroscopists may be found here. Dr. Richardson and colleagues would welcome your participation - if you are interested in contributing spectroscopy as outlined above and in the document, please contact Thomas Eversberg <thomas.everbserg at dlr.de>.
Also, the sequence for V1687 Cyg is in place, but because the star is so bright, small-scale charts will not show any comparison stars. Choose an 'A', 'AB', or 'B' scale chart (900, 450, or 180 arcmin field of view, respectively) for useful comparison stars. A 'C' scale chart (120 arcmin) will show sufficient (although faint) stars for CCD/PEP/DSLR work.
Coordinates (2000.0): R.A. 20 20 27.98 Dec. +43 51 16.3
Charts: Charts with a comparison star sequence for V1687 Cyg may be created using the AAVSO Variable Star Plotter (VSP).
Please submit observations to the AAVSO International Database using the name V1687 CYG.
Subscription Reminder about receiving Special Notices
You are reminded that beginning August 10, AAVSO Special Notices (and Alert Notices) will be sent ONLY to those who have subscribed via their AAVSO web account. An email was sent to all Special Notice subscribers on the current distribution list about this and giving instructions on how to subscribe using your (free) AAVSO account. This email may be found here.
A similar message was sent to AAVSO Alert Notice subscribers. If you want to receive the Alert Notices (highly recommended), be sure to subscribe via your AAVSO account before August 10. The relevant email may be found here.
It is recommended that you subscribe to both the Alert Notices and the Special Notices.
This Special Notice was compiled by Elizabeth O. Waagen.
----------------------------------
SUBMIT OBSERVATIONS TO THE AAVSO
Information on submitting observations to the AAVSO may be found at:
https://www.aavso.org/webobs
SPECIAL NOTICE ARCHIVE AND SUBSCRIPTION INFORMATION
A Special Notice archive is available at the following URL:
https://www.aavso.org/special-notice-archive
Subscribing and Unsubscribing may be done at the following URL:
https://www.aavso.org/observation-notification#specialnotices
-------------------------------------------------
Please support the AAVSO and its mission -- Join or donate today:
https://www.aavso.org/apps/donate/