white dwarf

Alert Notice 680: Monitoring of J0139 (ZTF J013906.17+524536.89) requested - corrected

Note: This Alert Notice has been edited to correct the mis-spelling of the short form of the star name. It is J0139, not J1039.  -  E. O. Waagen, September 18, 2019

September 18, 2019

AAVSO Forum threads (scroll to the bottom of a thread for latest posts):
 - Campaigns and Observing Reports
: https://www.aavso.org/j0139-campaign

Special Notice #76: Support for HST observations of SDSS074545, update


October 29, 2007: We have been informed by Paula Szkody that HST observations of SDSS074545 have been tentatively scheduled for the night of 2007 October 31/Nov 01 UT (approximate JD 2454405.56). Observations are pending ground-based confirmation that this cataclysmic variable is not in outburst and is thus faint enough to safely observe with HST. This decision will be made on the afternoon of Wednesday, 2007 October 31 UT, and so observations are critically needed during the night of 2007 October 30/31 UT (JD 2454404.5).

Alert Notice 513: Request for observations of GW Lib in support of HST observations

March 18, 2015: Dr. Paula Szkody, University of Washington, has requested our help in monitoring the cataclysmic variable GW Lib for upcoming Hubble Space Telescope observations, scheduled to be made during the window 2015 April 22-25 UT. Dr. Szkody also observed this object with HST in March 2011 and March 2010 (see AAVSO Alert Notices 433 and 417, respectively).

Alert Notice 451: Monitoring of the Symbiotic Variable RT Cru Requested

January 27, 2012: The symbiotic variable RT Cru has brightened in hard x-rays. Dr. Jeno Sokoloski, Columbia University, has requested AAVSO assistance in monitoring RT Cru both now and in the future to see if it is doing anything unusual in the optical. The Swift/BAT hard X-ray light curve shows RT Cru has apparently been gradually brightening over the past few years.