One of two radar corner reflectors installed at Piñon Flat Observatory. The JPL-design reflectors are large enough (2.4 m) to saturate the phase information from the ground pixel. Nearby GPS receiver will be used to check the stability of the corner reflector. The two corner reflectors, spaced 600 m apart, are aimed at descending pass of ERS and Radarsat. We plan to examine the phase stability of interferograms over time. In addition we plan to examine of the phase relationship between the corner reflector and the nearby ground surface to determine how the phase of the ground reflection is effected by environmental parameters such as moisture and temperature.

The amplitude image of two radar reflectors installed at the Piñon Flat Observatory. This is the sum of three images collected on 5/28/97, 4/23/97, and 3/19/97. Grid spacing is 1 pixel (7.9 meters in range, 4 meters in azimuth).

The ERS SAR amplitude image of Piñon Flat before installation of radar reflectors. This is the sum of two images collected on 12/20/95 and 12/19/95.	The ERS SAR amplitude image of Piñon Flat after installation of radar reflectors. This is the sum of three images as mentioned above.

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