Request for observations of GW Lib and V842 Cen in support of HST observations
March 3, 2010
Dr. Paula Szkody (U. Washington) has requested the help of AAVSO observers
to provide monitoring of two cataclysmic variables, GW Lib and V842 Cen,
in support of Hubble Space Telescope observations in March 2010.
Observations of both objects are requested beginning immediately, with
intensive observations requested beginning 48 hours prior to the scheduled
HST visit. The first observation of GW Lib has now been scheduled for
2010 March 11 03:45 UT (JD 2455266.6563); intensive observations by the
AAVSO community are requested beginning 2010 March 9 UT (JD 2455264.5).
Observations of V842 Cen are expected to be scheduled during the dates of
2010 March 18-22.
GW Lib and V842 Cen are dwarf novae/novae that have undergone outbursts in
the past. Observations of both sources are requested to guarantee to
ground controllers at STScI that they are below V~14.0 which is considered
the safe limit for the Cosmic Origins Spectrograph. Positive observations
are preferred if at all possible, however any fainter-than below V=14 is
useful.
Details about the V842 Cen observations will be issued via Alert Notice
when they are finalized.
The GW Lib observations are tentatively scheduled for 2010 March 11 03:45
UT pending confirmation that the star remains in quiescence. Please
promptly report all observations of this star to the AAVSO via WebObs.
The use of WebObs will ensure the fastest delivery of your data to Dr.
Szkody and STScI. We recommend using at least the "143" (AUID
000-BBW-012) and "147" (000-BBW-026) comparisons for fainter-than
estimates. We note that GW Lib is an infrequent outburster, and it is
highly unlikely that it will rise above its current brightness around
V=17.0 on March 11. However, STScI will still require confirmation of
this to ensure the safety of the Hubble Space Telescope and thus your
observations may be key to triggering these observations.
GW Lib is located at the following (J2000) coordinates:
RA: 15 19 55.45 , Dec: -25 00 25.30
Charts for GW Lib may be plotted using AAVSO VSP:
http://www.aavso.org/observing/charts/vsp/index.html?pickname=GW%20Lib
Please report all observations of GW Lib to the AAVSO using the name "GW
LIB".
This AAVSO Alert Notice was prepared by Matthew Templeton.
SUBMIT OBSERVATIONS TO THE AAVSO
Information on submitting observations to the AAVSO may be found at:
http://www.aavso.org/observing/submit/
US $69.99
