Valles Marinerus on Mars

A great rift of the surface of Mars extends nearly a quarter of the way around the planet.

火星表面有一条巨大的裂谷，延伸至几乎绕行 planet 的四分之一。

"The largest canyon in the Solar System cuts a wide swath across the face of Mars. Named Valles Marineris, the grand valley extends over 3,000 kilometers long, spans as much as 600 kilometers across, and delves as much as 8 kilometers deep. By comparison, the Earth's Grand Canyon in Arizona, USA is 800 kilometers long, 30 kilometers across, and 1.8 kilometers deep. The origin of the Valles Marineris remains unknown, although a leading hypothesis holds that it started as a crack billions of years ago as the planet cooled. Recently, several geologic processes have been identified in the canyon. The above mosaic was created from over 100 images of Mars taken by Viking Orbiters in the 1970s. " NASA description.

太阳系中最大的峡谷横跨火星表面，其名为瓦尔拉斯·马里尼西斯（Valles Marineris），这个巨大的峡谷长达约3000公里，最宽处达600公里，最深处达8公里。相比之下，地球上的大峡谷（位于美国亚利桑那州）长800公里，宽30公里，深1.8公里。瓦尔拉斯·马里尼西斯的成因尚不清楚，尽管有一种主流假说认为，它起源于数十亿年前，当行星冷却时形成了一条裂缝。最近，几个地质过程已被识别出与峡谷有关。上述拼接图是根据1970年代维金轨道器（Viking Orbiters）拍摄的火星上超过100张照片拼接而成。