Special Notice #381: HST/COS observations of SDSS J100658.40+233724.4

March 5, 2014: HST/COS are being scheduled for the U Gem-type dwarf nova SDSS J100658.40+233724.4, the 40th and final target of the major CV observing campaign organized in 2012 by Drs. Boris Gaensicke, Joseph Patterson, Arne Henden, and 13 other astronomers (see AAVSO Alert Notice 471 and note below). A precise time will be announced later, but the scheduled HST observing window is:

SDSS J100658.40+233724.4  2014 Mar. 20 or 21 UT (to be determined)

Please observe SDSS J100658.40+233724.4 closely through the end of March. AAVSO observations show SDSS J100658.40+233724.4, usually around 18.3 V at minimum, can be as faint as magnitude 20.02 V (LSTA, S. Littlefair, Sheffield, England) and as bright as 15.662 V at maximum (GFB, W. Goff, Sutter Creek, CA).

Coordinates (2000.0):
SDSS J100658.40+233724.4   R.A. 10 06 58.42  Dec. +23 37 24.6

Charts may be created using the AAVSO Variable Star Plotter (http://www.aavso.org/vsp).

Please report observations as soon as possible to the AAVSO International Database using the name SDSS J100658.40+233724.4. If an outburst is detected, please report observations immediately. Many thanks!

Details of the HST/COS CV campaign and specific observing instructions may be found in AAVSO Alert Notice 471 (http://www.aavso.org/aavso-alert-notice-471). Related AAVSO Special Notices may be found via the Observing Campaigns page (http://www.aavso.org/observing-campaigns). AAVSO Special Notice #371 (http://www.aavso.org/aavso-special-notice-371) is the most recent one that pertains to the campaign.

AAVSO observers have played a crucial role in this campaign from the beginning, and good coverage of this last target is equally important. Thank you for your valuable contributions!

This AAVSO Special Notice was compiled by Elizabeth O. Waagen.


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