Two Years at Meridiani Planum: Results from the Opportunity Rover

@article{Squyres2006TwoYA,
  title={Two Years at Meridiani Planum: Results from the Opportunity Rover},
  author={Steven W. Squyres and Andrew H. Knoll and Raymond E. Arvidson and Benton C. Clark and John P. Grotzinger and Bradley L. Jolliff and Scott M. McLennan and Nicholas J. Tosca and James F. Bell and Wendy M. Calvin and William H. Farrand and Timothy D. Glotch and Matthew P. Golombek and Kenneth E. Herkenhoff and J. R. Johnson and G{\"o}star Klingelh{\"o}fer and Harry Y. McSween and Albert S. Yen},
  journal={Science},
  year={2006},
  volume={313},
  pages={1403 - 1407}
}
The Mars Exploration Rover Opportunity has spent more than 2 years exploring Meridiani Planum, traveling ∼8 kilometers and detecting features that reveal ancient environmental conditions. These include well-developed festoon (trough) cross-lamination formed in flowing liquid water, strata with smaller and more abundant hematite-rich concretions than those seen previously, possible relict “hopper crystals” that might reflect the formation of halite, thick weathering rinds on rock surfaces… 
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