AAVSO HOME > publications > special notice
AAVSO Special Notice #193

Request for photometry of the recurrent nova U Scorpii
February 8, 2010

Dr. Bradley Schaefer has requested increased optical coverage of the
recurrent nova U Scorpii through the end of February 2010 at least. Of
greatest interest are calibrated multicolor photometry to follow the
evolution of the optical spectrum throughout the outburst, and intensive
time-series photometry to study flickering in the system and to time the
eclipses.  Recent photometry of U Scorpii has indicated that the nova
ejecta shell has become optically thin, making the central star visible
again.  Time series photometry will be used to study the eclipses of the
system; multicolor photometry will be used to study changes in color of
the system caused by dust and/or emission lines. Estimated eclipse times
may be found on the AAVSO Campaign page for U Sco:

Recently, Schaefer discovered that U Sco exhibited a sharp drop in
brightness in the light curve at t > 30 days using the Harvard plate
archives.  This feature is not covered at all in modern data, and
photometry is strongly encouraged to track both the total light output
and the color changes.  We note that in addition to instrumental
photometry, visual observations are also strongly encouraged.  Visual
observers who notice a sharp drop in brightness from one night to the
next are strongly encouraged to report such observations to the AAVSO as
quickly as possible.  It is expected that any sudden drop in light will
happen during a two week window centered on 2010 March 1 (JD 2455257).

U Scorpii is located at the following (J2000) coordinates:

        RA: 16:22:30.78 , Dec: -17:52:42.8

Customized charts for U Scorpii may be generated using AAVSO VSP:


For more information on U Scorpii and to track the progress of this
observing campaign, please visit http://www.aavso.org/news/usco.shtml .

Please promptly submit all observations to the AAVSO using the name "U

This AAVSO Special Notice was prepared by M. Templeton.


Information on submitting observations to the AAVSO may be found at:


A Special Notice archive is available at the following URL:

Subscribing and Unsubscribing may be done at the following URL: