Fig. 3From: An in-flight plasma diagnostic package for spacecraft with electric propulsionThe plasma sensor of the EPDP. (a) The entrance grid of the retarding potential analyzer is in the slanted face, and the plane Langmuir probe with guard ring is on the top face. (b) The view into the sensor shows the four grids and the segmented collector. (The two lateral empty bores in the slanted face are for the red-tag covers used before launch.)Back to article page