水手峡谷: 火星的大峡谷

2024年11月10日

Valles Marineris: The Grand Canyon of Mars
Image Credit: NASA, USGS, Viking Project

Explanation: 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. Several geologic processes have been identified in the canyon. The featured mosaic was created from over 100 images of Mars taken by Viking Orbiters in the 1970s.

Tomorrow’s picture: comet tails

水手峡谷: 火星的大峡谷
影像提供: NASA, USGS, Viking Project

说明: 太阳系最大的峡谷，在火星的表面划出一道宽深的凹痕。名为水手峡谷的这个雄伟裂谷，绵延的长度超过3,000公里，最宽处有600公里，并往下刨了约8公里深。相较之下，位于美国亚利桑那州的大峡谷，长约只有800公里、宽30公里、深1.8公里。水手峡谷的成因目前仍不明，但最广为接受的假说认为：远在数十亿年前火星冷却时，一道小裂缝后来演变成现今的峡谷。科学家已在此峡谷中，辨认出数种地质演化过程。上面这张拼嵌主题影像，是由100多张1970年代海盗号航天器所拍的火星照片组合而成。

明日的图片: comet tails