A Lunar Rille
Credit: Apollo 10,
NASA
Explanation: What could cause a long indentation on the
Moon? First discovered over 200 years ago with a small telescope,
rilles (rhymes with pills) appear all over the
Moon. Three types of
rilles are now recognized:
sinuous rilles, which have many meandering curves,
arcuate rilles which form sweeping arcs, and
straight rilles, like
Ariadaeus Rille pictured above. Long rilles such as
Ariadaeus Rille extend for hundreds of kilometers.
Sinuous rilles are now thought to be remnants of ancient lava flows, but the origins of arcuate and linear rilles are still a
topic of research. The
above linear rille was photographed by the
Apollo 10 crew in 1969 during their historic approach to only 14-kilometers above the
lunar surface. Two months later,
Apollo 11, incorporating much knowledge gained from
Apollo 10, landed on the Moon.
جميع المعلومات والصور فى هذه المشاركة وما يتبعها من مشاركات منسوخة من هذه الصفحة من موقع وكالة ناسا ومن الروابط الموجودة بنفس الصفحة
http://antwrp.gsfc.nasa.gov/apod/ap021029.html
وعلى من يعتمد علينا فى النسخ الإشارة إلى المصدر الأصلى ووضع روابط الموقع الأصلى للصور والمعلومات
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