Special Notice #340: HST/COS observations 2013 March 8 and March 9
March 6, 2013: Further to AAVSO Alert Notice 471 (http://www.aavso.org/aavso-alert-notice-471) and AAVSO Special Notice #339 (http://www.aavso.org/aavso-special-notice-339), HST/COS is scheduled to observe two of the dwarf novae in the CV campaign back-to-back:
on 2013 March 8:
SDSS J103533.03+055158.4 2013 March 8 07:42:37 through 15:04:27 UT
(V=18.8 at minimum, has eclipses)
on 2013 March 9:
SDSS J143544.02+233638.7 2013 March 9 08:35:01 through 13:40:17 UT
(V=18.2 at minimum)
Observations are crucial beginning now and continuing through one night after the HST observations. About 24-36 hours before the planned observations the HST/COS scheduling team will make the final decision whether to observe each system.
As instructed in AAVSO Alert Notice 471, for CCD observers, simultaneous photometry [shortly before, during, and after the HST observations] would be ideal. For the magnitude estimates, a nightly V measurement from now through the HST observations and a day beyond would be best. If positive visual observations are possible, they are welcome, as are visual fainter-than observations fainter than magnitude 15.0.
The next HST/COS target is scheduled to be V485 Cen:
V485 Cen 2013 March 16 03:02:56 through 09:44:57 UT
V485 Cen, a dwarf nova, is V=18.2 at minimum and V=14 at maximum.
SDSS J103533.03+055158.4 R.A. 10 35 33.03 Dec. +05 51 58.6
SDSS J143544.02+233638.7 R.A. 14 35 44.02 Dec. +23 36 38.7
V485 Cen R.A. 12 57 23.18 Dec. -33 12 05.7
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 names SDSS J103533.03+055158.4, SDSS J143544.02+233638.7, and V485 CEN, respectively. If an outburst is detected, please report observations immediately. Many thanks!
This AAVSO Special Notice was compiled by Elizabeth O. Waagen.
SUBMIT OBSERVATIONS TO THE AAVSO
Information on submitting observations to the AAVSO may be found at:
SPECIAL NOTICE ARCHIVE AND SUBSCRIPTION INFORMATION
A Special Notice archive is available at the following URL:
Subscribing and Unsubscribing may be done at the following URL:
Last Updated: March 6, 2013 - 2:47pm