Skip to main content

dwarf nova

Alert Notice 371: Support for XMM-Newton Observations of SS Aurigae

March 6, 2008: Dr. Patrick Godon (Villanova University / STScI) requests observations of the dwarf nova SS Aurigae (AAVSO Designation 0605+47) during the next several weeks in support of XMM-Newton X-ray observations. They request nightly visual and instrumental observations to determine whether the star was in outburst or quiescence during the observation scheduled for 2008 March 22/23 UT. Observations before, during, and after the scheduled X-ray observations will be used in their final analysis. Please begin observing now, and continue until at least April 5.

Alert Notice 379: Support for Spitzer observations of tremendous outburst amplitude dwarf novae (TOADs)

May 16, 2008 : Dr. Steve Howell (NOAO) requests monitoring of a subset of the known and suspected tremendous outburst amplitude dwarf novae (TOADs) in support of Spitzer Space Telescope observations of these objects. Observers are asked to increase their monitoring of the objects in the table below in support of this campaign.  We note that several of these objects -- notably the WZ Sge stars WZ Sge, GW Lib, and V455 And -- are not expected to superoutburst during the next year, but observations are still encouraged in case they exhibit unexpected behavior.  

Special Notice #367: Outburst of the UGWZ star UZ Bootis

July 26, 2013

Carey Chiselbrook (CCY; Georgia, United States) reports via the AAVSO Forums that the WZ Sge-type variable UZ Bootis is in outburst.  It was observed visually at magnitude 12.8 on 2013 Jul 26 02:00 UT (JD 2456499.58194).  The outburst was confirmed by Walter MacDonald (MDW; Ontario, Canada) imaged the field and found UZ Boo at V=12.69 03:25 UT (JD 2456499.6394).  Observations of UZ Bootis -- both visual estimates and CCD time series -- are encouraged throughout the outburst.

Special Notice #363: HS 2214+2845 (= V513 Peg) obs critical now

July 16, 2013: Based on your observations, the HST/COS team will be making the final decision tomorrow afternoon (2013 July 17) or the next morning whether to observe the dwarf nova HS 2214+2845 = V513 Peg on:

V513 Peg (HS 2214+2845) 2013 July 18 21:08:59 through July 19 01:04:23 UT

V513 Peg is 16.8V at minimum and 12.5V at maximum. Please monitor V513 Peg closely through July 19.

Special Notice #362: OR And and AX For obs critical now

July 8, 2013: The VY Scl variable OR And continues in its low state, so it has been scheduled for HST/COS observations. Based on your observations, the HST/COS team will be making the final decision tomorrow morning (2013 July 9) whether to observe OR And on:

OR And 2013 July 10 11:47:01 through 15:56:12 UT

OR And is ~18V in its low state and ~14.5V in its high state.

HST/COS is scheduled to observe the SU UMa variable AX For on the next day:

Special Notice #361: CC Scl observations DATE REVISED

June 24, 2013: The date given in AAVSO Special Notice #360 for the HST/COS  observations of the SU UMa-type dwarf nova CC Scl has been REVISED from June 27 to:

Special Notice #358: BD Pav obs critial tonight

June 12, 2013: Based on your observations, the HST/COS team will be making the final decision tomorrow morning (2013 June 13) whether to observe BD Pav.

Your observations tonight (June 12/13) are CRITICAL. HST/COS is scheduled to observe the eclipsing dwarf nova BD Pav:

BD Pav 2013 June 14 04:40:42 through 09:46:09 UT

If you can observe BD Pav, a few V-band snapshots would be sufficient and very helpful. BD Pav is 15.4V at minimum and 12.4V at maximum.


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