The Large Area Telescope (LAT), under development for launch by NASA in
2007 on the GLAST mission, will have unprecedented sensitivity for gamma
rays in the range ~20 MeV to >300 GeV. However, most parameters of the LAT
will not seem remarkable at other wavelengths. The effective collecting
area will be ~1 m^2 and the width of the point-spread function will range
from many degrees below 100 MeV to ~0.1 deg above 10 GeV, with significant
tails at all energies. Some design elements do mitigate these
shortcomings: the LAT has an enormous field of view, ~2.2 sr, and will be
operated in a scanning mode so that no observing time is lost to
occultations by the earth. Celestial fluxes are low, however, and even
with the large field of view the anticipated rate of celestial gamma rays
is 2-2.5 Hz. Most of these will be from the diffuse interstellar gamma-ray
emission of the Milky Way, and a large fraction of the point sources
responsible for the remainder have variable emission. These considerations
demand careful approaches to the analysis of LAT data, which we expect to
yield thousands of new gamma-ray point sources. The strategies that are
being explored to maximize the scientific return from GLAST will be described.
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