claim: Salt River Valley is a river valley that contains the Phoenix metropolitan area.
evidence: SPEX -LRB- the Spectropolarimeter for Planetary EXploration -RRB- is a single-channel , high-precision polarimeter for the characterization of planetary atmospheres .. It is intended for planetary science missions , but it could with minor modifications also be used for Earth observation by a microsatellite , such as the Dutch FAST-D project .. planetary science. planetary science. microsatellite. Miniaturized satellite. FAST-D. Formation for Atmospheric Science and Technology