Mars's image as a dust bowl may need a makeover. Dark streaks seen forming in summer and fading in winter might be signs of water flowing just beneath the surface. The appearance of streaks on sloping ground, including light streaks seen by NASA's Mars Global Surveyor spacecraft, has been attributed to present-day liquid water. But the link is not watertight - avalanches of dust could also be to blame. Now, NASA's Mars Reconnaissance Orbiter (MRO) has revealed a previously unknown group of seasonal dark streaks in Mars's southern hemisphere that may be caused by flowing water.
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机译：火星作为集尘碗的形象可能需要改造。夏季形成的深色条纹在冬季逐渐消失，可能是水在表层下方流动的迹象。倾斜地面上的条纹出现，包括NASA的“火星全球测量师”（Mars Global Surveyor）航天器看到的轻微条纹，归因于当今的液态水。但是联系并不是水密的-雪崩也应归咎于雪崩。现在，美国宇航局的火星侦察轨道器（MRO）揭示了火星南半球先前未知的一组季节性暗条纹，这可能是水流造成的。
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