In the image, river surfaces, roads, and streets, being smooth and flat, appear dark, whereas buildings, being strong corner reflectors, tend to be light (bright). Moist and bare fields show up in various darker shades but those with crops have lighter tones. The more rugged terrain (ridges with notable topographic relief) resemble those in an aerial photo, in which hill shadows are prominent, such as at lower Sun angles. The brighter slopes are oriented towards the aircraft, which flew along the bottom of image, and are at near range. Note that as the look angle increases (towards top), a general darkening (because of an overall drop in signal return), and more distorting of terrain features, occur.

By flying the radar along parallel flight lines, so that it always illuminates from the same direction (thus, the aircraft acquires signals only while flying in one direction) and maintains appropriate incidence angles, it acquires strips of images with identical shading characteristics, which allows us to merge them into mosaics. The image below is a composite of radar strips taken during a flight series over an uneven hilly terrain making up part of an igneous/metamorphic shield in the Nigeria/Cameroon border region of western Africa. This mosaic is about 97 km (60 mi) on a side.

8-9: Fit the first larger-scale image of Harrisburg (above) into this mosaic. What don't you see in both these images that is often present in Landsat images on a transient basis? In the K-band image, something in the valley near the Juniata River is evident that you probably can't see in the X-band mosaic; what? ANSWER

The image below is a composite of radar strips taken during a flight series over an uneven hilly terrain making up part of an igneous/metamorphic shield in the Nigeria/Cameroon border region of western Africa. This mosaic is about 97 km (60 miles) on a side.