V485 Cen observations crucial tonight through Sunday night

[PTS]

AAVSO Special Notice #341

V485 Cen observations crucial tonight through Sunday night March 14, 2013

Further to AAVSO Alert Notice 471
(http://www.aavso.org/aavso-alert-notice-471) and AAVSO Special Notice #340 (http://www.aavso.org/aavso-special-notice-340),
HST/COS is scheduled to observe the dwarf nova V485 Cen on 2013 March 16:

V485 Cen 2013 March 16 03:02:56 through 09:44:57 UT

Your observations are crucial through one night after the HST observations. The HST/COS scheduling team will make the final decision whether to observe V485 Cen based on observations from tonight, so please try to observe this system. V485 Cen is
V=18.2 at minimum and V=14 at maximum.

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.

Coordinates (2000.0)
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 name V485 CEN. 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:
http://www.aavso.org/webobs

SPECIAL NOTICE ARCHIVE AND SUBSCRIPTION INFORMATION

A Special Notice archive is available at the following URL:
http://www.aavso.org/special-notice-archive

Subscribing and Unsubscribing may be done at the following URL:
http://www.aavso.org/observation-notifi ... ialnotices