Skip to main content

Alert Notice 450: Request for observations of SDSS J080434.20+510349.2‭ ‬in support of HST observations

Due to the New England winter storm currently affecting the area, phone coverage at the AAVSO may be much reduced until Wednesday. The staff is still available via email, and we suggest using that method to contact us if you need assistance.

October 25‭, ‬2011: Dr‭. ‬Paula Szkody‭ (‬University of Washington‭) ‬has requested the help‭ ‬of AAVSO observers in monitoring the WZ Sge-type cataclysmic‭ ‬variable SDSS J080434.20+510349.2 (SDSS0804+51)‭ ‬in support of Hubble Space Telescope ultraviolet‭ ‬spectroscopic observations scheduled for 20:52:40‭ - ‬23:32:35‭ ‬2011‭ ‬November 3‭ ‬UT‭ (‬the night of Wednesday‭, ‬November 2/3‭)‬ ‭(‬JD 2455869.36991-‭.‬48096‭). ‬Nightly observations are requested‭ ‬beginning immediately and continuing through November 30‭. ‬This monitoring is crucial to these observations‭. ‬This campaign is similar to Dr‭. ‬Szkody's one on V455‭ ‬And‭ (‬see AAVSO Alert‭ ‬ Notice 448‭). ‬

The primary purpose of the monitoring is to know whether SDSS0804+51‭ ‬is in quiescence‭; ‬if it is in outburst it will be too bright for‭ ‬the HST instrumentation‭. ‬The decision whether to go forward with‭ ‬the HST observations will be made the evening of Tuesday‭, ‬November‭ ‬1/2‭, ‬so the nights of October 31‭/‬November 1‭, ‬November 1/2‭, and 2/3‭ ‬are the most critical for observations to be reported‭. ‬Positive visual or V observations are preferred if at all possible‭, ‬but fainter-than observations below V=14‭ ‬are useful‭ (<‬14.0‭ ‬or‭ ‬fainter‭). ‬Therefore‭, ‬nightly observations are sufficient for now‭; ‬2-3‭ ‬observations per night are requested during the nights of October‭ ‬31‭/‬November 1‭ ‬through November 4/5‭, ‬after which nightly observations‭ ‬may be resumed‭.‬

For CCD observers‭, ‬Dr‭. ‬Szkody writes‭, "[‬We‭] ‬will also be summing the‭ ‬spectra to obtain UV light curves‭. ‬Simultaneous photometry‭ [‬shortly‭ ‬before‭, ‬during‭, ‬and after the HST observations‭] ‬would be great for‭ ‬CCD observers‭. ‬B filter would be best for a light curve‭, ‬although‭ ‬for the magnitude estimates‭, ‬a V measurement would be best‭. ‬An‭ ‬uninterrupted light curve would be better than cycling between filters‭."‬

During quiescence SDSS0804+51‭ ‬is around magnitude V=17.5‭. ‬According to‭ ‬observations in the AAVSO International Database‭, ‬the last outburst‭ ‬of SDSS0804+51‭ ‬occurred September 22‭, ‬2010‭, ‬when it reached visual‭ ‬magnitude 12.2‭ ‬and was brighter than about magnitude 15‭ ‬until‭ ‬October 19‭, ‬2010‭.‬

SDSS J080434.20+510349.2 (SDSS0804+51, ‬AUID 000-BCY-525‭) ‬is located‭ ‬at the following‭ (‬J2000‭) ‬coordinates‭:‬

‭     ‬RA‭: ‬08‭ ‬04‭ ‬34.20‭   ‬Dec‭. +‬51‭ ‬03‭ ‬49.2

Charts for SDSS J080434.20+510349.2‭ ‬may be plotted using AAVSO VSP‭.‬

Please report all observations of SDSS0804+51‭ ‬to the AAVSO as‭ ‬SDSS J080434.20+510349.2 or SDSS0804+51‭.‬

Thank you for your observing efforts and valuable observations‭!‬

This AAVSO Alert Notice was prepared by Elizabeth Waagen‭.‬

‭---------------------------------------------------‬
SUBMIT OBSERVATIONS TO THE AAVSO

Information on submitting observations to the AAVSO may be found at‭:‬
http‭://‬www.aavso.org/webobs

ALERT NOTICE ARCHIVE AND SUBSCRIPTION INFORMATION

An Alert Notice archive is available at the following URL‭:‬
http‭://‬www.aavso.org/alert-notice-archive

Subscribing and Unsubscribing may be done at the following URL‭:‬
http‭://‬www.aavso.org/observation-notification#alertnotices
 

AAVSO 49 Bay State Rd. Cambridge, MA 02138 aavso@aavso.org 617-354-0484