All Sky HST Schedulability Plots
The all-sky plots show the number of schedulable 2-gyro HST orbits in
the given time frame. White areas of the plot are not viewable; no
targets should be selected in those regions. Dark blue areas
have limited visibility during the given time frame. The green and yellow
areas have the best visibility.
Both the ecliptic and Galactic equator are displayed. The location of
the Sun (yellow) and anti-Sun (black) are shown at the beginning
and end of the time range.
Scheduling becomes problematic when there are a large number of
observations at the same RA; that is, it will probably be difficult to
achieve high completion rates for programs that concentrate many orbits on a
single target, such as the HDF or the Galactic Center.
The maximum observatory scheduling
efficiency is obtained when the observing pool is well spread,
matching the contouring in the plots. Observers should be encouraged
to select targets that follow the contour weighting. Not
all programs can do this, of course.
Two quantitative measures of the contouring levels
are provided: 1) area of sky, and 2) frequency
of HST scheduling opportunities (orbits). The
upper measure shows what percentage of the sky
lies within each color contour region. The lower
measure shows the percentage of scheduling
opportunities (orbits) that exist within each
color contour. The left-most non-zero value for
the sky-area measure shows the percentage of the
sky (all are properly cosine-declination weighted)
Visibility from November 15, 2008 - January 31, 2009
Visibility from February 01, 2009 - May 15, 2009.
