This Notre Dame et. al. proposed Discovery mission will help answer the questions, "Do other Earth-sized planets exist? Are they common or rare? Is our solar system typical or a freak?"

As to how it works, note...
"The microlensing technique only works with planetary systems that are in the foreground of the Galactic bulge
or the inner Galactic disk. A planetary system in this
area acts as a gravitational lens that bends and amplifies the light from the objects behind it. As planets orbit their star, they will slightly perturb the gravitational lens and hence cause a brief variation in the light seen from the Earth. These variations provide the mass of the planet and the distance between the planet and its star. The GEST observatory would have a 1.5 metre mirror and a CDD camera containing 1.3 billion pixels."

This technique is NOT dependent on the planet's orbital inclination.

Another side benefit is the use of the scope to detect Kuiper Belt Objects during the months that the galactic
center is not visible (behing our sun).

-philw (chear chear for old notre dame)