[Aavso-photometry] AAVSO Campaigns Update

Tue Mar 10 11:53:36 EDT 2009

Hello everyone,

The past year has been a busy and productive one for the AAVSO and its
observers, as more and more people become observers and submit their
data. The AAVSO has assisted with a number of observing campaigns over
the past year, and we're overdue for a review of AAVSO campaign activity
and results.

The spring of 2008 saw the completion of one of our major campaign
efforts, assisting Dr. Paula Szkody with Hubble Space Telescope
observations of a number of dwarf novae believed to have pulsating white
dwarf primaries.  In order for those observations to occur, telescope
operators had to be confident that these six objects were not in
outburst during their observing windows.  AAVSO observers monitored all
of them, and provided the necessary data for HST operators to give these
important observations the go-ahead.  All the data were obtained
successfully, and we're looking forward to seeing the results in print
soon.

Another major observing effort last year was monitoring of high-mass
X-ray binaries, on behalf of a team led by Dr. Gordon Sarty.  He and a
number of AAVSO observers obtained photometry along with new
high-resolution spectroscopy obtained at the Dominion Astrophysical
Observatory in Victoria, British Columbia.  Sarty and collaborators are
attempting to refine the periods of a number of HMXBs -- binary stars
consisting of a massive secondary star, and either a neutron star or
black hole primary.  One paper on the star LSI+61 235 was recently
published in Monthly Notices of the Royal Astronomical Society (2009;
vol 392, p1242), and we look forward to seeing more results in print
soon!

A long-term campaign we're thus far happy to present null results on is
the monitoring campaign for the recurrent fast nova U Sco, requested by
Dr. Bradley Schaefer.  Schaefer has asked for regular monitoring of U
Sco and rapid notification in the event of an outburst.  U Sco went
behind the Sun at the end of last year, and it was feared that it
might've erupted and faded away during solar conjunction.  However,
AAVSO observers did their best to detect this object shortly after it
emerged from behind the Sun, and provided confirmation that not only was
it not in outburst, but that it was faint enough that an outburst during
conjunction could be safely ruled out!  AAVSO observers are continuing
to monitor this object, and (fingers crossed) we hope to catch this fast
nova on the rise some time during 2009.  If and when we receive a
positive detection, we may set in motion a number of telescopes around
the world (and some in orbit) to observe this star in earnest.  It is
hoped that multiwavelength observations may provide clues as to how and
why U Sco and other recurrent novae behave the way they do.

Not all observations turn out the way we hope, and that's as true in
your backyard as it is with satellites in orbit.  Although the AAVSO
observers did a fantastic job with this campaign, the Spitzer Space
Telescope was not able to obtain data for any of the tremendous outburst
amplitude dwarf novae (TOADs) requested by Dr. Steve Howell.  Although a
few stars in his list went into outburst last year, the Spitzer
satellite had extraordinarily strong constraints as to what objects it
could observe and when.  In this case, the stars quite literally didn't
align in our favor, and thus the project couldn't get the data they
wanted.  As always, Dr. Howell was very, very appreciative of the work
the observers put in. And remember, as with all data submitted to the
AAVSO, no observations ever go to waste -- all data from campaign
observers is submitted to the AAVSO archives, and thus the light curves
for these stars got an extra bump in coverage during the year. 
Regardless of whether there's an active campaign, these high-amplitude,
infrequently-outbursting dwarf novae are interesting in their own right,
and observations are always encouraged.

The AAVSO continues to support several other campaigns, with new
campaigns being activated as others reach completion.  As an example, we
continue to monitor the dwarf novae YZ Cnc, Z Cam, and EM Cyg to support
radio observations by the VLA.  We continue to get data for all of these
stars, but often there are gaps of a few days between observations, and
that's long enough that we haven't been able to trigger radio
observations yet this year. Observations in 2007 produced some exciting,
novel results -- the first known detection of a radio jet in a dwarf
nova outburst -- and it would be fantastic to be able to detect this in
another star.  Please consider contributing observations to this
campaign!

Several new campaigns have been initiated over the last few months as
well, including long-term monitoring of the suspected eclipser V1412 Aql
for Dr. Arlo Landolt.  Although the campaign is a tough one, it is
particularly exciting because the deep eclipses which Landolt and one
other group observed in the 1980's suggest that the white dwarf may be
completely eclipsed by an extrasolar planet.  A detection of another
eclipse would be the first confirmed transiting exoplanet around a white
dwarf star.  We don't know when or how often we expect to see eclipses,
so if you have an open slot in your observing queue, please consider
making a few measurements of this star!

As always, we maintain an up-to-date list of campaigns on the AAVSO
website, and encourage you to browse this list and find something you
might like to try.  We have campaigns ranging from visual monitoring for
outbursts all the way to requests for high-precision calibrated
time-series, and there's something there for everyone.  For more
information, please visit our website:

 	http://www.aavso.org/news/campaigns.shtml

Finally, I have to mention "the big one" coming up for 2009 -- the
upcoming eclipse of the mysterious binary epsilon Aurigae.  This star,
which goes into eclipse once every 27 years, is being observed by a
number of amateur and professional observers around the world during
2009 and 2010, and it's also a prominent part of the AAVSO's
participation in the International Year of Astronomy.  Epsilon Aurigae
is a fascinating star; even though it's visible to the naked eye, its
nature remains mysterious -- we still aren't even sure what exactly is 
eclipsing what!  For more information on Epsilon Aurigae, see the 
January 2008 Variable Star of the Season:

 	http://www.aavso.org/vstar/vsots/eps_aur.shtml

Hopefully more answers to this mystery will be forthcoming during 2009,
and we hope that you participate in this and all other AAVSO Observing
Campaigns during the coming year!

I have one final request to AAVSO Campaign participants: if you have any
comments or questions about AAVSO observing campaigns, please email me
at matthewt (at) aavso.org.  I'd like to know how to increase
participation in campaigns, and enhance the collaborations between AAVSO
observers and the researchers requesting campaigns.  If you have any
suggestions, please let me know!

Many thanks to everyone who participated in AAVSO Campaigns during the
past year!

Clear skies,

 	Matthew Templeton
 	AAVSO Campaign Coordinator